Abstract PD11-01: PD11-01 Evaluation of the PD-1 Inhibitor Cemiplimab in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL

Background: I-SPY2 is a multicenter, phase 2 trial using response-adaptive randomization within biomarker subtypes defined by hormone-receptor (HR), HER2, and MammaPrint (MP) status to evaluate novel agents as neoadjuvant therapy for high-risk breast cancer. The primary endpoint is pathologic complete response (pCR). Cemiplimab (Cemi) is a PD-1 inhibitor approved for the treatment of NSCLC, cutaneous basal, and squamous cell cancer. Here, we report current efficacy rates of Cemi in combination with paclitaxel followed by AC.

Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only HER2 negative (HER2-) patients were eligible for this treatment; HR positive (HR+) patients had to be MP high risk. Treatment included paclitaxel 80 mg/m2 IV weekly x 12 and Cemi 350 mg IV given q3weeks x 4, followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel x 12 followed by AC every 2-3 weeks x 4. All patients undergo serial MRI imaging; and imaging response (at 3 weeks, 12 weeks and prior to surgery) were used along with accumulating pCR data to continuously update and estimate pCR rates for trial arms. Analysis was modified intent to treat. Patients who switched to non-protocol therapy count as non-pCR. The goal is to identify (graduate) regimens with ≥85% Bayesian predictive probability of success (i.e. demonstrating superiority to control) in a future 300-patient phase 3 neoadjuvant trial with a pCR endpoint within responsive signatures. Cemi was eligible to graduate in 3 pre-defined signatures: HER2-, HR-HER2-, and HR+HER2-. To adapt to changing standard of care, we constructed “dynamic controls” comprising ‘best’ alternative therapies using I-SPY 2 and external data and estimated the probability of Cemi being superior to the dynamic control.

Results: 60 HER2- patients (28 HR+ and 32 HR-) received Cemi arm treatment. The control group included 357 patients with HER2- tumors (201 HR+ and 156 HR-) enrolled since March 2010. Cemi graduated in HR-/HER2- signature. Estimated pCR rates (as of June 2022) are summarized in the table.

Immune-related endocrine disorders include: hypothyroid (14.5%), adrenal insufficiency (10%), hyperthyroid (4.8%),) and thyroiditis (3.2%). Only one grade 3 adrenal insufficiency was observed. All immune related AE’s were manageable. Additional biomarker analyses are ongoing and will be presented at the meeting. Response predictive subtypes (Immune+ vs Immune-) and additional predictive biomarkers were assessed. Associations with pCR will be presented at SABCS.

Conclusion: The I-SPY 2 study aims to assess the probability that investigational regimens will be successful in a phase 3 neoadjuvant trial. Anti-PD-1 therapy with Cemi resulted in a higher predicted pCR rate in HR-/HER2- 55 rate% disease compared to control at 29%. Immune-mediated AE’s were observed. This data is consistent with previously published data using check point inhibitors in early-stage HR-/HER2- breast cancer.

Estimated pCR rates

Citation Format: Erica Stringer-Reasor, Rebecca A. Shatsky, Jo Chien, Anne Wallace, Judy C. Boughey, Kathy S. Albain, Hyo S. Han, Rita Nanda, Claudine Isaacs, Kevin Kalinsky, Zahi Mitri, Amy S. Clark, Christos Vaklavas, Alexandra Thomas, Meghna S. Trivedi, Janice Lu, Smita Asare, Ruixiao Lu, Maria Pitsouni, Amy Wilson, Jane Perlmutter, Hope Rugo, Richard Schwab, W. Fraser Symmans, Nola M. Hylton, Laura Van ’t Veer, Douglas Yee, Angela DeMichele, Donald Berry, Laura J. Esserman, I-SPY Investigators. PD11-01 Evaluation of the PD-1 Inhibitor Cemiplimab in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD11-01.

Abstract P3-09-01: Characterization of residual disease after neoadjuvant selective estrogen receptor degrader (SERD) therapy using tumor organoids in the I-SPY Endocrine Optimization Protocol (EOP)

Background: Treatment of estrogen receptor (ER)-positive breast cancer with selective estrogen receptor degraders (SERDs) frequently results in the loss or reduction of ER expression. Whether these changes are due to on-target effects of SERDs degrading ER or arise as a mechanism of tumor resistance with associated changes in cellular phenotypes remains unknown. It is critical to distinguish between these possibilities to accurately assess treatment response and determine the most appropriate subsequent therapy. To this end, we created and conducted molecular analyses on patient-derived organoid cultures from post-treatment tissue in patients receiving neoadjuvant SERD therapy for early-stage ER+ breast cancer in the I-SPY2 Endocrine Optimization Protocol (EOP). Methods: The I-SPY2 EOP study is a prospective, randomized substudy within the I-SPY TRIAL testing the oral SERD amcenestrant alone or in combination with letrozole or abemaciclib in stage 2/3 ER+ Her2-negative breast cancer. Enrollment is ongoing, with patients receiving amcenestrant neoadjuvantly for 6 months until the day before surgery. Tumor tissue is collected at baseline, 3 weeks, and at surgery. Organoids were generated from post-treatment surgical samples. Organoid cultures were optimized based on established methods (Dekkers et al., Nature Protocols, 2021) to assess ER levels and activity. Pre- and post-treatment tissue samples were also assessed for ER, PR, Ki67, and GATA3, a luminal marker and transcription factor that is functionally linked with ER, via immunohistochemistry. Results: In 7 patients with both pre- and post-treatment tissue samples including fresh surgical samples for organoid generation, the ER in baseline tumor tissue was >=90% in all patients, PR ranged from 40-90%, and Ki67 ranged from 5-30%. In post-treatment surgical tissue from these cases, ER ranged from 0-30%, PR from 0-50%, Ki67 from < 1%-10%, and GATA3 was positive in 5 of 5 cases tested to-date. The creation of organoids from residual disease at surgery was attempted for these 7 patients, with organoids successfully propagated in 5 cases thus far. 3 of 5 organoid cultures were ready for analysis and in all cases strong ER and PR expression in organoids was observed after culture for > 1 month in the absence of amcenestrant. Detailed gene expression profiling (including Mammaprint/Blueprint) and gene set enrichment analyses (GSEA) to assess for intrinsic breast cancer subtype and ER activity in each sample and corresponding organoid culture are in progress and will be reported with the full dataset. Conclusion: Patient-derived organoid culturing of residual disease after neoadjuvant endocrine therapy is feasible. Neoadjuvant treatment with a SERD can render ER and PR low or absent at the time of surgical resection, which does not necessarily imply the presence of endocrine therapy resistant disease. The use of organoids and additional IHC markers (GATA3) demonstrate that receptor negativity may be an indicator of the drug hitting its target, suggesting ER signaling is still intact. In general, patient-derived tumor organoid cultures modeling residual disease states can be a useful adjunct to existing methods used to monitor the effects of neoadjuvant endocrine therapy and is being explored in the I-SPY EOP trial.

Citation Format: Jennifer Rosenbluth, Christopher J. Schwartz, Tam Binh Bui, Shruti Warhadpande, Pravin Phadatare, Sigal Eini, Michael Bruck, Julissa Molina-Vega, Kami Pullakhandam, Nicole Schindler, Lamorna A. Brown Swigart, Christina Yau, Gillian Hirst, Rita Mukhtar, Karthik V. Giridhar, Olufunmilayo I. Olopade, Kevin Kalinsky, Cheryl A. Ewing, Jasmine M. Wong, Michael D. Alvarado, Laura Van’t Veer, Laura J. Esserman, Jo Chien. Characterization of residual disease after neoadjuvant selective estrogen receptor degrader (SERD) therapy using tumor organoids in the I-SPY Endocrine Optimization Protocol (EOP) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-09-01.

Abstract GS5-03: Evaluation of anti-PD-1 Cemiplimab plus anti-LAG-3 REGN3767 in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL

Background: I-SPY2 is a multicenter, phase 2 trial using response-adaptive randomization within biomarker subtypes defined by hormone-receptor (HR), HER2, and MammaPrint (MP) status to evaluate novel agents as neoadjuvant therapy for high-risk breast cancer. The primary endpoint is pathologic complete response (pCR). Cemiplimab is an anti-PD-1 inhibitor approved for the treatment of NSCLC and cutaneous basal and squamous cell CA. Lymphocyte activation gene 3 (LAG-3) binds MHC class II leading to inhibition of T-cell proliferation and activation and is often co-expressed with PD-1. REGN3767 is a fully humanized mAb that binds to LAG-3 and blocks inhibitory T-cell signaling. Concurrent blockade of LAG-3 with an anti-PD-1 may enhance efficacy of an anti-PD-1.

Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only HER2 negative (HER2-) patients were eligible for this treatment; HR positive (HR+) patients had to be MP high risk. Treatment included Paclitaxel 80 mg/m2 IV weekly x 12 and Cemiplimab 350 mg and REGN3767 1600 mg both given q3weeks x 4, followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel x 12 followed by AC every 2-3 weeks x 4. Cemiplimab/REGN3767 was eligible to graduate in 3 of 10 pre-defined signatures: HER2-, HR-HER2-, and HR+HER2-. The statistical methods for evaluating I-SPY 2 agents has been previously described. To adapt to changing standard of care, we constructed “dynamic controls” comprising ‘best’ alternative therapies using I-SPY 2 and external data and estimated the probability of Cemiplimab/REGN3767 being superior to the dynamic control. Response predictive subtypes (Immune+ vs Immune-) were assessed using pre-treatment gene expression data and the ImPrint signature.

Results: 73 HER2- patients (40 HR+ and 33 HR-) received Cemiplimab/REGN3767 treatment. The control group included [357 patients with HER2- tumors (201 HR+ and 156 HR-) enrolled since March 2010. Cemiplimab/REGN3767 graduated in both HR-/HER2- and HR+/HER2- groups; estimated pCR rates (as of June 2022) are summarized in the table. Safety events of note for Cemiplimab/REGN3767 include hypothyroidism 30.8%, adrenal insufficiency (AI) 19.2%, hyperthyroidism 14.1%, pneumonitis 1.3%, and hepatitis 3.8%. All were G1/2 except for 6 (7.7%) G3 AI and 3 (3.8%) G3 colitis. Rash occurred in 62.8%, 9% G3 and 2 pts (2.6%) had pulmonary embolism. X% of adrenal insufficiency cases required replacement therapy. 40 patients (11 HR+ and 29 HR-) in Cemiplimab/REGN3767 were predicted Immune+; 32 (29 HR+ and 3 HR-) were predicted Immune-. In the HR+ group pCR was achieved in 10/11 (91%) patients with Immune+ subtype compared with 8/29 (28%) with Immune- subtype. Additional biomarker analyses are ongoing and will be presented at the meeting.

Conclusion: The I-SPY 2 study aims to assess the probability that investigational regimens will be successful in a phase 3 neoadjuvant trial. Dual immune blockade with a LAG-3 inhibitor and anti-PD1 therapy resulted in a high predicted pCR rate both in HR-/HER2- (60%) and HR+/HER2- (37%) disease. The novel Imprint signature identified a group of HR+ patients most likely to benefit from this active regimen.

Table 1: Estimated pCR rates

Citation Format: Claudine Isaacs, Rita Nanda, Jo Chien, Meghna S. Trivedi, Erica Stringer-Reasor, Christos Vaklavas, Judy C. Boughey, Amy Sanford, Anne Wallace, Amy S. Clark, Alexandra Thomas, Kathy S. Albain, Laura C. Kennedy, Tara B. Sanft, Kevin Kalinsky, Hyo S. Han, Nicole Williams, Mili Arora, Anthony Elias, Carla Falkson, Smita Asare, Ruixiao Lu, Maria Pitsouni, Amy Wilson, Jane Perlmutter, Hope Rugo, Richard Schwab, W. Fraser Symmans, Nola M. Hylton, Laura Van’t Veer, Douglas Yee, Angela DeMichele, Donald Berry, Laura J. Esserman, I-SPY Investigators. Evaluation of anti-PD-1 Cemiplimab plus anti-LAG-3 REGN3767 in early-stage, high-risk HER2-negative breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS5-03.

Abstract P2-03-16: Quantifying estrogen and progesterone receptor status in early-stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series

Background: Recent guidelines regarding estrogen (ER) and progesterone (PR) receptor testing from the American Society of Clinical Oncology and College of American Pathologists defined a new reporting category of ER-low positive breast cancer for tumors with 1-10% ER expression by immunohistochemistry (IHC). The clinical implications of ER-low positivity are incompletely understood, especially in invasive lobular carcinoma (ILC), the second most common type of breast cancer. Given the rarity of low-ER positivity in ILC, we evaluated tumor features and outcomes associated with a spectrum of ER/PR positivity in a monoinstitutional ILC cohort. Methods: We analyzed cases of stage I-III ILC with available IHC reports. Based on prior published categories in ILC, we classified ER as low, medium, or high as defined by ER staining of 10–69%, 70–89%, and ≥90% respectively. PR negative, low, and high tumors were defined by 0%, < 20%, or ≥20% staining respectively. We used chi-squared tests, t-tests, and Cox proportional hazards models in Stata 16.1 to evaluate associations between ER/PR categories including clinicopathologic variables and event-free survival (EFS). Results: Of 744 cases, 24 (3.2%) were ER negative and 10 (1.3%) were ER-low positive as defined by 1-10% positive staining. 713 remaining cases had ER positivity ≥ 10% and comprised the cohort categories of ER low, medium, and high for this study (11.2%, 15.0%, and 73.8% respectively). In 751 cases with PR data, 122 (16.2%) were PR negative, 145 (19.4%) were PR low and 483 (64.3%) were PR high. ER high status was significantly associated with older age (mean 56.7, 56.7, and 60.6 years in ER low, medium, and high respectively, p=0.0005). ER low was associated with PR negative and low status (42.3% were PR neg/low and ER low, versus 37.4% with ER medium and 29.9% in ER high, p=0.045), and more likely to have overexpression of HER2 (9.7%, 9.0%, and 2.9% ER low, medium, high, respectively, p=0.002). ER low tumors were more likely to be grade 1 than ER medium or high (41.8%, 29.8% and 24.5% respectively, p=0.025), and have positive surgical margins (39.4%, 35.9% and 23.9% respectively, p=0.002). ER status was not associated with Ki67, stage, body mass index (BMI), lymphovascular invasion, lobular carcinoma in situ (LCIS), pleomorphic histology, local therapy, or chemotherapy use. In contrast, PR high was significantly associated with younger age (57.6 versus 63.5 years in PR low, p< 0.0001). PR low was associated with HER2 overexpression (8.6% versus 3.2% in PR high, p=0.002). PR low cases were more likely to present at higher stages (15.8% stage III versus 10.1% stage III in PR high, p=0.032), to be pleomorphic (16.8% versus 8.2%, p< 0.001), and to receive chemotherapy (30.8% versus 23.1%, p=0.022) but were less likely to have associated LCIS (64.0 versus 74.2%, p=0.004). PR status was not associated with Ki67, BMI, lymphovascular invasion, local therapy, or surgical margins. In a Cox proportional hazards model adjusting for age, stage, grade, pleomorphic histology, and chemotherapy use, ER category was not associated with EFS but both PR negative and PR low status each had significantly worse EFS compared to PR ≥20% (HR 3.5, 95% CI 1.8-6.7, p< 0.001 for PR negative, and HR 2.0, 95% CI 1.1-3.5, p=0.015 for PR low). The estimated cumulative 5-year EFS for patients with ER low, medium, and high tumors was 87.1%, 93.4%, and 90.1% respectively. The estimated cumulative 5-year EFS for patients with PR negative, low, and high tumors was 78.9%, 90.2%, and 92.7% respectively. Conclusions: Using ILC-specific categories for ER expression, we found associations between ER category and clinicopathologic variables but not with EFS. In contrast, PR negative and low status was associated with worse EFS. These findings highlight the importance of exploring the spectrum of ER/PR activity within ILC, a classically strongly hormone receptor-positive tumor type, using more quantitative methods.

Citation Format: Elle Clelland, Harriet T. Rothschild, Anne Patterson, Julissa Molina-Vega, Mandeep Kaur, Mary Kathryn Abel, W. Fraser Symmans, Jo Chien, Christopher J. Schwartz, Rita Mukhtar. Quantifying estrogen and progesterone receptor status in early-stage invasive lobular carcinoma of the breast: associated factors and outcomes in an institutional series [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-03-16.

Abstract P5-13-12: Immune signatures and MammaPrint (ultra) high risk class (MP2) as predictors of response to pembrolizumab combined with the TLR9 agonist SD101 in the neoadjuvant I-SPY 2 TRIAL

Background: Pembrolizumab, an anti-PD-1 immune checkpoint inhibitor, is approved for treatment in multiple cancers and has been shown to increase pathologic complete response (pCR) and survival in the neoadjuvant setting in breast cancer. Pembrolizumab combined with paclitaxel followed by doxorubicin/cyclophosphamide (P+T->AC) was evaluated in HER2- patients in the neoadjuvant I-SPY 2 TRIAL and graduated in the HER2-, HR+HER2- and triple negative (TN) signatures. Our biomarker analysis revealed that immune cell abundance and MP2 class predicts response in HR+HER2- patients whereas tumor-immune proximity scores (multiplex-IF) and signaling signatures (mRNA) predict response in TN patients. In an effort to further improve response, the TLR9 agonist SD101 was added to Pembro (P+S+T -> AC) for testing in I-SPY 2. While P+S increased estimated pCR rates relative to control (T->AC), it did not graduate for efficacy. To better understand the biology underlying response to P+S, we evaluated 31 expression based biomarkers relating to immune, ER and proliferation as predictors of response to P+S overall and within subtypes. Methods: Data from 72 patients (HR+HER2-: 45; TN: 27) treated with P+S were available. Pre-treatment FFPE biopsies were assayed using Agilent gene expression arrays. We evaluated genes/signatures representing 6 immune checkpoint/targets (CD274, PDCD1, TLR9, TIGIT, LAG3, and TIM3), 14 immune cell types (e.g., TILs, T cells, CD8 T cells, Tregs, cytotoxic cells, dendritic cells, mast cells, B cells, macrophages, and neutrophils), 3 T/B-cell prognostic (e.g., ICS5), 5 Tumor-immune signaling (e.g., STAT1, Chemokine12, TIS, and Geparsixto), and 1 TGFB signaling signatures as predictors of response to P+S. We also assess ESR1/PGR and proliferation, and the prognostic marker MP2 class. Signature scores were calculated as previously published. We used logistic modeling to assess biomarker performance (likelihood ratio test, p<0.05). This analysis was also performed in a model adjusting for HR status, and within receptor subsets. For the dichotomous MP1/2, we used Bayesian modeling to estimate the pCR rates of patients in each class. Multiple hypothesis testing adjustment was performed using the Benjamini-Hochberg method. Our statistics are descriptive rather than inferential and do not adjust for multiplicities of other biomarkers outside this study. Results: Higher levels of most (24/29) immune biomarkers associate with pCR in the population as a whole (BH LR p<0.05). Among target genes, CD274 and PDCD1 strongly associate with pCR; however, TLR9 did not associate with response. As seen in previous biomarker analyses of IO agents including Pembro, there are major differences in predictive biology between receptor subsets. Immune cell subpopulation abundance signatures (13/14) and T/B-cell prognostic signatures (3/3) associate with pCR in HR+HER2- but not TN subsets. Whereas tumor-immune signaling signatures (4/5) dominated by chemokines and cytokines associate with pCR in both HR+HER2- and TN subsets. In addition, high ESR1/PGR and low proliferation signature levels associate with response in HR+HER2-, as does MP1/2 class, with an estimated 45% pCR in MP2 versus 17% pCR in MP1. Analysis of multiplex-IF immune markers is pending. Conclusion: Though TN patients are more responsive to Pembro+SD101 and other immunotherapies than HR+HER2- patients, many more immune biomarkers associate with pCR in the latter group. Only tumor-immune signaling signatures associate with pCR in both HR+HER2- and TN subsets. Response in the HR+HER2- subset is higher in MP2 class, high-proliferation, lower-ER tumors. Lack of predictive signal for TLR9 may help explain why the addition of SD101 to Pembro failed to further boost response.

Citation Format: Denise M Wolf, Christina Yau, Michael Campbell, Hatem Soliman, Mark Magbanua, Ruixiao Lu, Nicholas O'Grady, Lamorna Brown-Swigart, Gillian Hirst, Laura Sit, Yvonne M Florence, I-SPY 2 TRIAL Investigators, Smita Asare, Doug Yee, Angie DeMichele, Don Berry, Laura Esserman, Jo Chien, Laura van 't Veer. Immune signatures and MammaPrint (ultra) high risk class (MP2) as predictors of response to pembrolizumab combined with the TLR9 agonist SD101 in the neoadjuvant I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-12.

Abstract PD9-04: Tumor-released circulating orphan non-coding RNAs reflect treatment response and survival in breast cancer

Background: Liquid biopsies have emerged as effective diagnostic tools in disease monitoring and minimal residual disease detection. Circulating tumor DNA (ctDNA) was recently shown to be a predictor of poor response and recurrence in breast cancer. However, ctDNA shedding from breast tumors can rapidly decrease during treatment, resulting in reduced sensitivity in measuring early changes in tumor response or residual cancer burden (RCB) after neoadjuvant chemotherapy (NAC). We recently reported the discovery of orphan non-coding RNAs (oncRNAs), a class of small RNAs that are not present in healthy cells, but emerge from cancer cells. Similar to ctDNA, tumor-released oncRNAs can be used to detect the presence of an underlying tumor; however, since they are actively released by cancer cells, their abundance in the cell-free compartment is substantially higher than ctDNA. Therefore, we hypothesized that monitoring circulating oncRNAs in blood permits a more sensitive approach to measuring treatment response (i.e., pathologic complete response, or pCR) and estimating RCB. Patients and Methods: Cell-free RNA (cfRNA) was extracted from ~1 ml sera of 72 breast cancer patients treated in the neoadjuvant I-SPY 2 TRIAL with NAC alone or combined with MK-2206 (AKT inhibitor) treatment. For each patient, treatment-naïve samples (T0) were compared with samples from post-treatment and prior to surgery (T3) time-point. RNA samples were subjected to small RNA sequencing (SMARTer), and the presence and abundance of cell-free oncRNA species were then determined by identifying and counting the reads that map to oncRNA loci across samples. Notably, oncRNAs species were pre-annotated from the Cancer Genome Atlas (TCGA), and our approach does not require bespoke personalized assays. We used a machine-learning model to compare abundance of cfRNA species before and after treatment (i.e., T3-T0) to predict pCR and RCB. For this, we split our cohort into a training and a testing set (48 and 24) and trained a model to simultaneously learn the presence of residual disease (pCR vs. no pCR) and its extent (RCB). We then measured the performance of our model on the held-out test data and the entire dataset. To confirm the robustness of our model, we also employed a leave-one-out strategy, whereby pCR and RCBIndex of each patient was predicted using a model that was trained on the other patients in the cohort. Finally, to assess the ability of our oncRNA-based model to risk-stratify patients who fail to achieve pCR (without having been explicitly trained on relapse data), we used the model’s oncRNA score to predict patients at the highest risk of distant recurrence (n=8 out of 36) and performed a multivariate Cox analysis, controlling for HR/Her2 status (median follow-up time was 4.8 years). Results: The model’s accuracy for predicting pCR—based on changes in circulating oncRNA species between T3 and T0—was 85% for the training data and 79% for the held-out test data (positive predictive value of 75% and negative predictive value of 83%) with combined accuracy of 83%; precision 86% and recall 83%; Pearson R=0.5 for RCB. A leave-one-out strategy showed similar performance (area under ROC of 0.77 versus 0.81 in train-test split). Finally, among the patients who failed to achieve pCR, we observed a significantly higher risk of distant recurrence in those with the highest scores (DRFS: hazard-ratio = 8.4, ANOVA P<0.05). Conclusion: In this study, we have shown that the changes in tumor-released oncRNA content of the blood are a significant predictor of clinical outcomes. Our results demonstrate that oncRNA fingerprints are blood-accessible, and allow us to build predictive models of tumor response. We are currently expanding this study to additional cohorts, and we expect to report the results for a longitudinal analysis that includes ~200 patients from I-SPY2.

Citation Format: Hani Goodarzi, Albertas Navickas, Jefferey Wang, Kristle Garcia, Mark J Magbanua, Lisa Fish, Lamorna Brown Swigart, Gillian Hirst, Denise Wolf, Christina Yau, Jo Chien, Carol Simmons, Amy Delson, Laura Esserman, Laura van 't Veer. Tumor-released circulating orphan non-coding RNAs reflect treatment response and survival in breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD9-04.

Abstract P5-18-02: Final findings from the CONTROL trial of diarrheal prophylaxis or neratinib dose escalation on neratinib-associated diarrhea and tolerability in patients with HER2+ early-stage breast cancer

Background: Neratinib (NERLYNX®), an irreversible pan-HER tyrosine kinase inhibitor, is approved for the extended adjuvant treatment of early-stage HER2+ breast cancer following adjuvant trastuzumab-based therapy and in combination with capecitabine for HER2+ metastatic breast cancer. Diarrhea is the most frequently reported on-target side effect associated with neratinib; in the ExteNET adjuvant trial, where no mandatory anti-diarrheal prophylaxis was used, 39.8% of patients reported grade 3 diarrhea and 16.8% of patients discontinued neratinib due to diarrhea. The CONTROL trial (Clinicaltrials.gov: NCT02400476) was designed to investigate pre-emptive antidiarrheal prophylaxis (loperamide alone or in combination with budesonide or colestipol) or neratinib dose escalation (DE) for the prevention of neratinib-associated diarrhea. Data for the loperamide, budesonide and colestipol cohorts have been reported previously [Barcenas et al. Ann Oncol 2020]. The final findings for the two DE regimen cohorts are reported here. Methods: CONTROL is an international, multi-cohort, open-label, phase 2 study. Patients ≥18 years of age with stage I-IIIc HER2+ breast cancer received oral neratinib (240 mg/day for 1 year) after trastuzumab-based adjuvant therapy. Patients were enrolled sequentially into separate cohorts investigating: 1) mandatory loperamide prophylaxis; 2) budesonide + loperamide; 3) colestipol + loperamide; 4) colestipol + loperamide PRN; 5) neratinib DE + loperamide PRN (two cohorts). DE1 schedule: neratinib 120 mg/day for week 1, 160 mg/day for week 2, then 240 mg/day from week 3 onwards to complete 12 months of treatment. DE2 schedule: neratinib 160 mg/day for weeks 1&2, 200 mg/day for weeks 3&4, then 240 mg/day from week 5 onwards up to 12 months. Both DE cohorts included loperamide PRN. Adverse events were graded according to NCI-CTCAE v4.0. Primary endpoint: incidence of grade ≥3 diarrhea. Results: A total of 563 patients were enrolled in CONTROL. All preventive strategies reduced the incidence of grade 3 diarrhea compared with that seen in ExteNET (historical control: 39.8%). Median cumulative duration of grade 3 diarrhea ranged from 2-3.5 days across the CONTROL study cohorts for the entire 12-month treatment period (compared with 5.0 days for ExteNET). The proportion of patients discontinuing neratinib because of diarrhea was decreased in all cohorts compared with ExteNET (16.8%), except for loperamide alone. Adoption of neratinib DE, particularly the 2-week DE schedule (DE1), most markedly reduced the incidence, severity, and duration of neratinib-associated diarrhea in CONTROL compared with ExteNET (see Table).

Conclusions: Neratinib DE + loperamide PRN during the first 2 weeks of treatment (DE1 cohort) was associated with the lowest rates of grade 3 diarrhea (13.3%) and diarrhea-related discontinuations (3.3%) compared with all other anti-diarrheal strategies investigated in CONTROL. These final findings from the study show improved tolerability of neratinib with all diarrhea prophylaxis strategies and suggest that neratinib DE1 with loperamide PRN allows patients to stay on treatment longer and receive the full benefit of neratinib therapy.

Table. Patient disposition and diarrhea characteristics: ExteNET vs CONTROL DE cohortsExteNET(n=1408)CONTROL DE1 (n=60)CONTROL DE2 (n=62)Patients completing 1 year of neratinib treatment, %617874Median duration of treatment, months (range)11.6 (2.5–11.9)12.0 (0.2–12.4)11.9 (0.3–14.5)Diarrhea, %Grade 339.813.327.4Grade 4<100Median cumulative duration of grade 3 diarrhea,a days52.52Discontinuations due to diarrhea, %16.83.36.5Dose reductions due to diarrhea, %26311Dose holds due to diarrhea, %341213aNo grade 4 diarrhea was reported in CONTROL.

Citation Format: Arlene Chan, Manuel Ruiz-Borrego, Gavin Marx, Adam Brufsky, Jo Chien, Michael Thirlwell, Maureen Trudeau, Ron Bose, José A García-Sáenz, Daniel Egle, Barbara Pistilli, Johanna Wassermann, Kerry A Cheong, Christian F Singer, Daniel Hunt, Navid Foruzan, Leanne McCulloch, Carlos H Barcenas. Final findings from the CONTROL trial of diarrheal prophylaxis or neratinib dose escalation on neratinib-associated diarrhea and tolerability in patients with HER2+ early-stage breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-18-02.

Abstract PD10-07: Chemokine12 (CK12) tertiary lymphoid gene expression signature as a predictor of response in 3 immunotherapy arms of the neoadjuvant ISPY 2 TRIAL - pembrolizumab with and without SD101, and durvalumab combined with olaparib - and in 9 other arms of the trial including platinum-based and dual-anti-HER2 therapies

Background: The CK12 expression signature consists of genes CCL2, CCL3, CCL4, CCL5, CCL8, CCL18, CCL19, CCL21, CXCL9, CXCL10, CXCL11, CXCL13 and was previously shown to associate with the presence of T and B cell rich tertiary lymphoid structures in melanoma and other cancers, and with better patient survival independent of tumor staging and treatment. I-SPY 2 is a biomarker-rich, phase II neoadjuvant platform trial for high risk early stage breast cancer. Here we leverage the I-SPY 2 biomarker program to test the hypothesis that this signature associates with sensitivity to neoadjuvant immunotherapies and potentially other classes cancer therapeutics in breast cancer. Methods: Data from 1130 patients across 12 arms of I-SPY2 (control (ctr): 210; veliparib/carboplatin (VC): 71; neratinib (N): 114; MK2206: 93; ganitumab: 106; ganetespib: 93; AMG386: 134; TDM1/pertuzumab(P): 52; H/P: 44; pembrolizumab (pembro): 69; durvalumab/olaparib (durva/olap): 71; pembro/SD101: 72) were available for analysis. Pre-treatment FF (n=987) or FFPE (n=143) biopsies were assayed using Agilent gene expression arrays. Signature scores were calculated as the average expression level across the 12 genes, after z-score normalization. We used logistic modeling to assess association with pCR in each arm in a model adjusting for HR and HER2 (likelihood ratio test, p<0.05). This analysis was also performed within HR/HER2 receptor subsets, numbers permitting. We also assessed differences in levels across HR/HER2 subsets using ANOVA and Tukey post-hoc testing. Our statistics are descriptive rather than inferential and do not adjust for multiplicities of other biomarkers outside this study. Results: CK12 levels associate with HR/HER2 status (ANOVA p=1.07E-14), with higher levels in TN and HR-HER2+ subsets and lower levels in HR+ groups. Overall, patients with higher levels of CK12 were significantly more likely to achieve pCR in all 3 IO arms: pembro (OR=3.4/1SD), pembro/SD101 (OR=4/1SD), and durva/olaparib (OR=2.5/1SD) (LR p<0.05), in a model adjusting for HR status. The CK12 performed favorably in predicting response to pembro/SD101 compared to several other genomic signatures measuring intratumoral immune response. Higher CK12 also associates with response to the ANG1/2 inhibitor AMG386, an agent known to have immune modulatory activity. Higher CK12 was moderately associated with pCR in the control (OR=2.0/1SD), neratinib (OR=1.7/1SD), veliparib/carboplatin (OR=2.0/1SD), ganitumab (OR= 1.7/1SD) and TDM1/P arms (OR=2.1/1SD). Within the HR+HER2- subset, CK12 associated with pCR in all three IO arms, and in the control, AMG386, ganitumab, and ganetespib arms. Within the smaller TN subset, it associated with response in pembro and pembro/SD101 arms but not in durva/olaparib, and in the neratinib and AMG386 arms. Chemokine12 mostly did not associate with pCR in HER2+ subsets, except for HR+HER2+ patients treated with neratinib, and HR-HER2+ patients in the original control arm (trastuzumab). Conclusion: The CK12 signature is highly predictive of complete pathologic response to immuno-oncology agents and other therapeutics supporting the role of the crosstalk within the tumor immune microenvironment in predicting response across subtypes. This gene expression signature can be readily obtained from microarrays and warrants further investigation in future arms of ISPY2 as a predictive biomarker.

Citation Format: Hatem Soliman, Denise Wolf, Jo Chien, Christina Yau, Michael Campbell, Mark Magbanua, Ruixiao Lu, Nicholas O'Grady, Lamorna Brown-Swigart, Gillian Hirst, Beverly Parker, Laura Sit, Smita Asare, Doug Yee, Angie DeMichele, Rita Nanda, Lajos Pusztai, Don Berry, Laura Esserman, Laura Van't Veer. Chemokine12 (CK12) tertiary lymphoid gene expression signature as a predictor of response in 3 immunotherapy arms of the neoadjuvant ISPY 2 TRIAL - pembrolizumab with and without SD101, and durvalumab combined with olaparib - and in 9 other arms of the trial including platinum-based and dual-anti-HER2 therapies [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD10-07.

Abstract PD9-04: Identification of biomarkers associated with therapeutic resistance: Quantitative protein/phosphoprotein analysis of ~750 patients across 8 arms of the neoadjuvant I-SPY 2 TRIAL for high-risk early stage breast cancer

Background: The goal of I-SPY 2 is to rapidly test novel therapies in addition to standard of care in high-risk breast cancer patients. It has resulted in increasing response rates, where pCR rates in TNBC and HR-HER2+ subsets have reached ~60% and ~75%, respectively. Yet, there remains a sizeable subset of non-responders, especially among HR+ patients. Identification of ‘universal’ resistance mechanisms may guide rational selection of agents to improve these patient's outcomes. Thus, we analyzed reverse phase protein array (RPPA) based quantitative protein/phosphoprotein data across arms to assess whether there are common mechanisms rendering these cancers resistant to all agent classes tested to date. Methods: 736 patients (260 HR+HER2-, 252 TN, 142 HR+HER2-, and 82 HR-HER2+; over 8 arms: 194 Ctr, 105 neratinib (N), 63 veliparib/carboplatin (VC), 128 AMG386 (anti-ANG1/2), 87 MK2206 (anti-AKT), 43 TH/pertuzumab (P), 49 TDM1/P, and 67 pembrolizumab (Pembro)) with pCR and RPPA data at the pre-treatment time point were considered for this analysis. 141 RPPA endpoints representing key cancer pathways were assessed for association with pCR using logistic regression modeling, with HR, HER2 and treatment arm as covariates (likelihood ratio test; p<0.05). Analysis was also performed in HR/HER2 subsets and within treatment arms. Markers were analyzed individually; multiple comparison correction (Benjamini-Hochberg) was applied to p-values. Our analysis is exploratory, and does not adjust for other biomarkers outside this study. Results: Prior to FDR correction, high levels of Cyclin D1, a cell cycle protein implicated in estrogen-mediated DNA damage repair, associate with non-pCR in the population as a whole and within all subtypes except for the HR-HER2+ subset; an association that retains significance after FDR correction overall as well as in HER2- and HR+HER2- subsets. Within individual arms, high Cyclin D1 predicted non-response in VC, control, and AMG386; and trends toward association in Pembro and N. In addition, high quantitative ER and phospho-androgen receptor (pAR; S650) associate with non-pCR in the population as a whole and in the HR+HER2- subset. For both ER and pAR the strongest association with non-pCR was in the Pembro arm. Candidates for universal sensitivity signals include immune proteins JAK-STAT (pSTAT5 (Y694) and pSTAT1 (Y701)) overall; and pERBB2/pEGFR for HER2+ patients. Conclusions: High levels of Cyclin D1, but not other cell cycle proteins, predict non-response to chemo-/targeted-therapy across arms and subtypes, suggesting that agents specifically targeting Cyclin D1 may increase chemo-sensitivity. ER/phospho-AR as global resistance signals suggest inclusion of anti-AR agents in combination therapy, and the need for new endocrine-based approaches.

Citation Format: Julia Wulfkuhle, Denise Wolf, Christina Yau, Lamorna Brown-Swigart, Rosa I Gallagher, Gillian Hirst, Laura Sit, Smita Asare, I-SPY 2 TRIAL Investigators, Nola Hylton, Angela DeMichele, Douglas Yee, Jo Chien, Hope Rugo, John Park, Kathy Albain, Rita Nanda, Debu Tripathy, Richard Schwab, Don Berry, Laura Esserman, Laura van t' Veer, Emanual Petricoin, III. Identification of biomarkers associated with therapeutic resistance: Quantitative protein/phosphoprotein analysis of ~750 patients across 8 arms of the neoadjuvant I-SPY 2 TRIAL for high-risk early stage breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD9-04.

Abstract P3-09-11: Modulation of the immune microenvironment in high risk DCIS

Background. Ductal carcinoma in situ (DCIS) is a risk factor for the subsequent development of invasive breast cancer. Features of DCIS that are associated with a high risk of a subsequent event include large size (> 5 cm), high grade, comedo necrosis, palpable mass, hormone receptor negativity, and HER2 positivity. We have previously shown that immune infiltrates in DCIS are positively associated with these high-risk features, suggesting that manipulating the immune microenvironment in high risk DCIS could potentially alter disease progression.

Objectives. The objectives of this study were: 1). to define dose limiting toxicities, tolerability, and feasibility of intralesional injection of an immune checkpoint inhibitor (pembrolizumab) into DCIS; and 2). to determine response rate as measured by an increase in total T cells or CD8+ T cells from baseline to post treatment.

Methods. Study participants received 2 intralesional injections of pembrolizumab, 3 weeks apart, with surgery approximately 3 weeks after the 2nd dose. Multiplex immunofluorescence analyses were used to compare immune cell populations in pre-treatment biopsies to post-treatment surgical specimens. Tissue samples were stained with two 6-plex immune panels using Opal immunofluorescence reagents (Perkin Elmer) on a fully automated Ventana Discovery platform, imaged with a Vectra 3 system and analyzed with inForm software (Perkin Elmer).

Results. The intralesional injections were well tolerated and there were no systemic toxicities observed. Multiplex immunofluorescence analyses demonstrated significant increases in total T cells, as well as cytotoxic CD8+ T cells, following therapy. We also observed a significant positive correlation between the change (pre- vs. post-therapy) in Ki67+ T cells (proliferating T cells) with the increase in total T cells, suggesting that immune checkpoint inhibition removed the “brakes” from the T cells, allowing them to proliferate. Changes in macrophage, B cell, and Treg numbers pre- vs. post-therapy were not significant. Despite an increase in T cell infiltrates, there were no measurable indicators of an anti-tumor response: no reduction in lesion size by MRI, no reduction in proliferation of DCIS cells (Ki67 staining), and no increase in cell death (cleaved caspase 3 staining). Spatial analyses indicated that in most cases the T cell expansion (both total T cells and CD8+ T cells) occurred predominantly in the stroma, not among the DCIS cells in the ducts.

Conclusions. We met the objectives of our study: 1). we demonstrated the safety and feasibility of intralesional injection of an immune checkpoint inhibitor (pembrolizumab) in high risk DCIS; and 2). we demonstrated that local immunotherapy resulted in the local proliferation/expansion of T cells. However we did not observe any change in the size of the lesions by MRI. In addition, there was no evidence for T cell killing at the cellular level, suggesting that even though there was an expansion of T cells, there are other factors at play such as immune exclusion or possibly immunosuppression of their killing ability. These results suggest that combination of pembrolizumab with another agent(s) will be needed to achieve a more complete response.

Citation Format: Michael Campbell, Jasmine Wong, Emma McCune, Harriet Rothschild, Tristan Loveday, Jennifer Bolen, Cliff Hoyt, Scott VandenBerg, Jo Chien, Laura Esserman. Modulation of the immune microenvironment in high risk DCIS [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-09-11.

Abstract P5-15-01: The use of 18F-FDG PET/CT as an initial staging procedure for stage II-III breast cancer reduces false positives, costs, and time to treatment: A multicenter value analysis in the I-SPY2 trial

Introduction: Diagnostic metastatic staging imaging (SI) for asymptomatic stage I-II patients (pts) is not routinely recommended, but is warranted in stage II-III pts with high risk biological subtypes, where previous trials have shown up to a 15% rate of de novo metastatic disease. NCCN guidelines endorse CT CAP and bone scan (STD) for stage III pts, but not PET/CT, and PET/CT is not covered in most parts of the country. We present data on the performance and value of PET/CT.

Methods: Data were available for 799 high risk clinical stage II-III pts screened for I-SPY2 at UCSF, Uminn, UAB, and Georgetown. Of these, 564 pts ranging in age from 25-81 (median = 48) had complete records that were retrospectively reviewed for SI and potential false positives (FP), defined as incidental findings on SI proven benign by subsequent workup. Economic evaluation was conducted from the payer perspective using the mean national 2018 Medicare Physician Fee Schedule and representative costs from the UCSF billing department. The incremental cost effectiveness ratio (ICER) measured the cost of using PET/CT per percent patient (pt) who avoided a FP.

Results: The rate of de novo metastatic disease was 4.8% (38/799), range 3.6-6.4%. Of the 564 pts with complete records, diagnostic SI varied significantly among the four sites (p < 0.0001). STD was used for most pts at UAB (92.8%, 141/152) and Georgetown (85.7%, 54/63), while PET/CT was used for most pts at UCSF (86.6%, 226/261) and Uminn (63.6%, 56/88). Chest X-ray was used for 29.5% (26/88) at Uminn. There were significantly more pts with FP in the group that received STD (22.1%, 51/231) vs. PET/CT (11.1%, 33/298) (p < 0.05). Mean time between incidental finding on SI to determination of FP was 10.8 days. When controlling for institution, mean time from cancer diagnosis to initiation of neoadjuvant chemotherapy was significantly different between STD (44.3 days) and PET/CT (37.5 days) groups (p < 0.05). When aggregating the four sites using mean costs from the 2018 Medicare Physician Fee Schedule, the mean cost/pt was $1132 for STD vs. $1477 for PET/CT. The mean increase in price from baseline SI costs due to FP workup was $216 (23.6%) for STD vs. $65 (4.6%) for PET/CT. The ICER was $31 per percent pt who avoided a FP. When analyzing UCSF pts alone using representative reimbursements from Medicare, the mean cost/pt was $1236 for STD vs. $1081 for PET/CT; using representative reimbursements from Anthem Blue Cross, the mean cost/pt was $3080 for STD vs. $1662 for PET/CT. The ICERs were -$10 and -$95 per percent pt who avoided a FP, respectively.

Conclusion: As compared to STD metastatic staging workup, PET/CT added value by decreasing FP two-fold. This reduced direct costs of FP workup procedures that took a mean time of 10.8 days to resolve. PET/CT also accelerated treatment start. Reducing the chance of FP workup for metastatic disease is of enormous value to pts. Our data establish the value of PET/CT for staging in our high risk clinical stage II-III trial population and highlight the need for alignment between hospital pricing strategies and payer coverage policies in order to deliver high value care to pts.

Citation Format: Hyland CJ, Varghese F, Yau C, Beckwith H, Khoury K, Varnado W, Hirst G, Chien J, Yee D, Isaacs C, Forero-Torres A, Esserman L, Melisko M, I-SPY2 Consortium. The use of 18F-FDG PET/CT as an initial staging procedure for stage II-III breast cancer reduces false positives, costs, and time to treatment: A multicenter value analysis in the I-SPY2 trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-15-01.

Abstract P2-13-03: The impact of neratinib with or without anti-diarrheal prophylaxis on health-related quality of life in HER2+ early-stage breast cancer: Analyses from the ExteNET and CONTROL trials

Background: Neratinib is an irreversible pan-HER tyrosine kinase inhibitor. ExteNET, a randomized placebo-controlled phase III study, showed that neratinib given for 12 months after trastuzumab-based adjuvant therapy significantly improved 2-year (HR 0.67; 95% CI 0.50–0.91; p=0.0091) and 5-year (HR 0.73; 95% CI 0.57-0.92; p=0.008) iDFS in pts with early-stage HER2+ breast cancer. Anti-diarrheal prophylaxis was not mandated by protocol; grade 3/4 diarrhea occurred in 40% of pts with a median cumulative duration of 5 days. The phase II CONTROL study was initiated to investigate the effectiveness of various prophylactic regimens in the prevention of neratinib-associated diarrhea. Loperamide (L) alone or in combination with add-on agents targeting underlying inflammation [i.e. budesonide (BUD)] or bile acid malabsorption [i.e. colestipol (COL)] were tested. We report longitudinal HRQoL findings from both ExteNET and CONTROL.

Methods: Pts with early-stage HER2+ breast cancer who had received trastuzumab-based adjuvant therapy were eligible for both studies. In ExteNET, pts received neratinib or placebo for 12 months. In CONTROL, pts received neratinib for 13 x 28-day cycles combined with L, L + BUD or L + COL for 1 or 2 cycles (see table for schedules). HRQoL was assessed using Functional Assessment of Cancer Therapy–Breast (FACT-B), v4.0, at baseline, months 1, 3, 6, 9, 12 (ExteNET) or baseline, cycles 2, 4, 7, 10, 13 (CONTROL). Changes in scores from baseline were considered to be clinically meaningful if greater than the lowest estimate for an 'important difference' (ID) reported in the literature. Evaluable pts were required to have HRQoL assessments at baseline and at least 1 post-baseline. ClinicalTrials.gov: NCT00878709 (ExteNET); NCT02400476 (CONTROL).

Results: HRQoL findings are summarized in the table. Hospitalization rates due to diarrhea: 1.5% (neratinib + L), 0% (other cohorts) in CONTROL; and 1.4% (neratinib), 0.1% (placebo) in ExteNET.

  Mean change from baselineStudyCohort/GroupM1M3M6M9M12 FACT-B TOTAL (ID range: 7–8 points)CONTROLN + La,b (N=40)–3.8–4.5–1.5–2.5–3.3 N + L + BUDa,b,c (N=62)–6.0–4.9–1.6–3.6–4.5 N + L + COLa,b,d (N=125)–3.8–2.0–4.0–4.6–3.6 N + L prn + COLa,d (N=85)–1.8–1.54.0e––ExteNETN + L prna (N=1124)–4.6–3.4–3.5–3.3–3.7 P (N=1188)–1.7–3.5–2.9–2.9–2.8 FACT-B PWB (ID range: 2–3 points)CONTROLN + La,b (N=40)–4.0–2.3–1.9–2.4–2.3 N + L + BUDa,b,c (N=62)–3.2–2.1–1.4–1.7–1.7 N + L + COLa,b,d (N=125)–2.8–2.0–2.4–2.5–2.4 N + L prn + COLa,d (N=85)–2.8–1.80.0e––ExteNETN + L prna (N=1124)–2.9–1.9–1.7–1.6–1.5 P (N=1188)–0.6–0.8–0.7–0.6–0.4C, cycle; L, loperamide; M, month; N, neratinib; prn, as needed; PWB, physical well-being. CONTROL cut-off: 1 May 2018. aN 240 mg qd for 13 x 28d cycles or 12 months; bL 4 mg, then 4 mg tid d1-14, then 4 mg bid d15-28 or d15-56, then prn; cBUD 9 mg qd d1-28; dCOL 2 g qd d1-28; en=1.

Conclusions: Adjuvant neratinib with or without anti-diarrheal prophylaxis was associated with small decreases in HRQoL. With the exception of the FACT-B PWB subscale, HRQoL changes did not reach clinically meaningful thresholds. Follow-up in CONTROL is ongoing.

Citation Format: Delaloge S, Hurvitz S, Chan N, Bose R, Jankowitz RC, Thirlwell M, Láng I, ten Tije A, Trudeau M, Osborne CR, Shen Z-Z, Lalla D, Xu F, Hunt D, Olek E, Tripathy D, Rugo HS, Chien J, Chan A, Barcenas CH. The impact of neratinib with or without anti-diarrheal prophylaxis on health-related quality of life in HER2+ early-stage breast cancer: Analyses from the ExteNET and CONTROL trials [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-13-03.

Abstract P2-09-02: Modulation of the immune microenvironment in high risk DCIS by intralesional injection of anti-PD-1 (pembrolizumab)

Background. Ductal carcinoma in situ (DCIS) is a risk factor for the subsequent development of invasive breast cancer. Features of DCIS that are associated with a high risk of a subsequent event include large size (> 5 cm), high grade, comedo necrosis, palpable mass, hormone receptor negativity, and HER2 positivity. We have previously shown that immune infiltrates are positively associated with these high-risk features, suggesting that manipulating the immune microenvironment in high-risk DCIS, for example via checkpoint blockade, could potentially alter disease progression.

Methods. In this phase 1 pilot study we investigated changes in the immune microenvironment of high risk DCIS after intralesional injection of anti-PD-1 (pembrolizumab). Study participants received 2 intralesional injections of pembrolizumab, 3 weeks apart, with surgery approximately 3 weeks after the 2nd dose. The study started with a dose of 2 mg/injection (1/100 of the standard 200 mg iv dose), then escalated to 4 mg and 8 mg, with 3 patients at each dose. Tissue samples from pre-treatment biopsies and post-treatment surgical resections were stained with two 6-plex immune panels using Opal immunofluorescence reagents (Perkin Elmer) on a fully automated Ventana Discovery platform, imaged with a Vectra 3 system and analyzed with inForm software (Perkin Elmer). An algorithm for tumor/stroma segmentation developed in inForm was used to randomly select 10 high power fields (hpfs) for imaging. Cell phenotype maps were generated for each of these hpfs for each sample. Cell densities were determined per area of stroma, DCIS, or total tissue and averaged across all hpfs for a given case. Spatial analyses were performed to quantitate co-localization of immune cells with DCIS cells.

Results. The intralesional injections were easily administered and well tolerated. No systemic toxicities were observed at any dose. MRI imaging demonstrated no change in the size of lesions after treatment. Multiplex immunofluorescence analyses demonstrated heterogeneous responses ranging from dramatic increases in T cells, in particular CD8+ T cells, in cases which had a T cell infiltrate prior to therapy, to no post-therapy T cell infiltrate in cases with a pre-therapy immune desert. We also observed increases in B cells and macrophages and a decrease in the ratio of FoxP3+ T cells to CD8+ T cells, the latter mainly due to a significant increase in CD8+ cells, as opposed to a decrease in FoxP3+ cells. Spatial analyses indicated that in some cases, despite a marked increase in T cells post therapy, these cells did not co-localize with DCIS cells, indicating a state of immune exclusion.

Conclusions. We have demonstrated the safety and feasibility of intralesional injection of an immune checkpoint inhibitor (pembrolizumab) in high risk DCIS. In some patients we observed a dramatic change in the immune microenvironment, with an increase in T cells, B cells, and macrophages, and a decrease in the FoxP3:CD8 ratio, even at a dose that is 1/100 of the standard intravenous clinical dose. An expansion study is underway in which patients will receive 4 injections of pembrolizumab at 3 week intervals prior to going to surgery to determine if more injections/time will increase response rate.

Citation Format: Campbell MJ, McCune E, Rothschild H, Bolen J, VandenBerg S, Chien J, Wong J, Esserman L. Modulation of the immune microenvironment in high risk DCIS by intralesional injection of anti-PD-1 (pembrolizumab) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-09-02.

Abstract P2-13-01: Efficacy of neratinib in hormone receptor-positive patients who initiated treatment within 1 year of completing trastuzumab-based adjuvant therapy in HER2+ early-stage breast cancer: Subgroup analyses from the phase III ExteNET trial

Background: The international, randomized, placebo-controlled phase III ExteNET trial showed that 1 year (yr) of neratinib 240 mg/day after trastuzumab-based adjuvant therapy significantly improved invasive disease-free survival (iDFS) in 2840 patients with early-stage HER2+ breast cancer at 2 yr (hazard ratio 0.67; 95% CI 0.50–0.91; p=0.009) [Chan 2016] and 5 yr (hazard ratio 0.73; 95% CI 0.57-0.92; p=0.008) [Martin 2017]. A prespecified subgroup analysis by hormone receptor (HR) status suggested enhanced efficacy with neratinib in patients with HR+ (2-yr hazard ratio 0.51; 95% CI 0.33–0.77) vs. HR– tumors (2-yr hazard ratio 0.93; 95% CI 0.60–1.43). The efficacy of neratinib was also greater in patients who initiated treatment within 1 yr of prior trastuzumab compared with those who started neratinib later. The European Medicines Agency's Committee for Medicinal Products for Human Use recently recommended neratinib for use in patients with HR+ tumors who initiate treatment within 1 yr of completing trastuzumab-based adjuvant therapy. Subgroup analyses from ExteNET examining iDFS benefits in this patient population are presented here.

Methods: Patients with early-stage HER2+ breast cancer who completed trastuzumab-based (neo)adjuvant therapy were assigned to oral neratinib 240 mg/day or placebo for 1 yr. Randomization was stratified by HR status (determined locally before trial entry), nodal status, and trastuzumab regimen. Endocrine therapy was allowed in patients with HR+ disease. The primary endpoint, iDFS, was tested by 2-sided log-rank test and hazard ratios (95% CI) were estimated using Cox proportional hazards models. Kaplan-Meier methods were used to estimate iDFS rates. Secondary endpoints were DFS-DCIS, time to distant recurrence, distant DFS, and CNS recurrences. The primary analysis was conducted at 2 yr, and a sensitivity analysis conducted at 5 yr. Clinicaltrials.gov:NCT00878709.

Results: Of the 2840 patients (neratinib, n=1420; placebo, n=1420), 1631 (57%) had HR+ disease (neratinib, n=816; placebo, n=815). Most (93%) HR+ patients were receiving endocrine therapy at baseline. 1334 of 1631 (82%) patients with HR+ tumors were randomized to start neratinib within 1 yr of last trastuzumab dose (neratinib, n=670; placebo, n=664). iDFS benefits from neratinib in this population are shown in the table. Secondary endpoints were also improved with neratinib vs. placebo in this population. Safety data in this subset will be presented at the meeting.

Table. iDFS in patients with an interval between last trastuzumab dose and randomization of ≤1 yr

 HR+ population (N=1334)ITT population (N=2297)  Hazard ratiob  Hazard ratiob  Δ, %a(95% CI)P-valueΔ, %a(95% CI)P-value2-yr analysisc+4.50.490.002+2.90.630.006  (0.30–0.78)  (0.45–0.88) 5-yr analysisd+5.10.580.002+3.20.700.006  (0.41–0.82)  (0.54–0.90) aDifference in iDFS rates between neratinib vs. placebo; bNeratinib vs. placebo; cData cut-off: July 2014; dData cut-off: March 2017

Conclusions: Neratinib may have enhanced and sustained efficacy in patients with HR+ disease who initiate treatment within 1 yr of trastuzumab-based adjuvant therapy.

Citation Format: Gnant M, Martin M, Holmes F-A, Jackisch C, Chia SK, Iwata H, Moy B, Martinez N, Mansi J, Morales S, Ruiz-Borrego M, von Minckwitz G, Buyse M, Delaloge S, Bhandari M, Murias Rosales A, Galeano T, Fujita T, Luczak A, Barrios CH, Saura C, Rugo HS, Chien J, Johnston SR, Spencer M, Xu F, Barnett B, Chan A, Ejlertsen B. Efficacy of neratinib in hormone receptor-positive patients who initiated treatment within 1 year of completing trastuzumab-based adjuvant therapy in HER2+ early-stage breast cancer: Subgroup analyses from the phase III ExteNET trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-13-01.

Abstract 961: Intralesional injection of anti-PD-1 (pembrolizumab) results in increased T cell infiltrate in high risk DCIS

Background. Accumulating evidence shows a correlation between tumor-infiltrating lymphocytes (TILs), in particular the presence of CD8+ T cells, in cancer tissue and favorable prognosis in various malignancies. Less is know about the role of the immune microenvironment in the context of pre-malignant lesions such as ductal carcinoma in situ (DCIS). In a previous study of women with DCIS, we observed that high numbers of activated CD8+ T cells within the DCIS lesions were associated with good outcomes while low numbers associated with high risk features and poor outcomes. These results suggest that manipulating the immune microenviroment in DCIS, for example via checkpoint blockade, could potentially alter disease progression. Methods. We recently initiated a phase 1 pilot study to investigate changes in the immune microenvironment of high risk DCIS after intralesional injection of anti-PD-1 (pembrolizumab). Study participants were given 2 intralesional injections of pembrolizumab 3 weeks apart with surgery approximately 3 weeks after the 2nd dose. The study started with a dose of 2 mg/ml (1/100 of the standard 200 mg/ml iv dose), then escalated to 4mg/ml and 8 mg/ml, with 3 patients at each dose. FFPE tissue samples from pre-treatment biopsies and post-treatment surgical resections were immunostained using Opal reagent kits (Perkin Elmer) on a fully automated Ventana Discovery platform, imaged with a Vectra automated imaging system, and analyzed with inForm software (Perkin Elmer). A 7-plex panel, consisting of mAbs to CD3, CD8, CD68, PD-1, PD-L1, Ki67, and cytokeratins, was used. An algorithm for tumor/stroma segmentation developed in inForm was used to randomly select 7-10 high power fields (hpfs) for imaging. Cell phenotype maps were generated for each of these hpfs for each sample. Cell densities were determined per area of stroma, DCIS, or total tissue and averaged across all hpfs for a given case. Results. We are completing our 2nd cohort of patients, and there have been no adverse clinical events. The injections are easily administered and well tolerated. By MRI imaging, there was no change in the size of lesions after the treatment. All patients have proceeded to surgical resection. Following intralesional pembrolizumab injection, multiplex fIHC analyses indicated an increase in CD8+ T cells, which in some areas was striking. This increase was mainly observed within the epithelial DCIS regions, as opposed to a lesser increase in stromal CD8+ T cells. We also observed an increase in CD68+ macrophages. Conclusions. We have demonstrated the safety and feasibility of intralesional injection of an immune checkpoint inhibitor (pembrolizumab) in high risk DCIS. Further, we have shown that this immunotherapeutic intervention results in a change in the immune microenvironment, with an increase in both T cells and macrophages, even at a dose that is 1/100 of the standard intravenous clinical dose.

Citation Format: Michael J. Campbell, Emma McCune, Jennifer Bolen, Scott VandenBerg, Jo Chien, Jasmine Wong, Laura Esserman. Intralesional injection of anti-PD-1 (pembrolizumab) results in increased T cell infiltrate in high risk DCIS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 961.

Abstract CT106: Efficacy of pertuzumab/trastuzumab/paclitaxel over standard trastuzumab/paclitaxel therapy for HER2+ breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL

Background: Pathologic complete response (pCR) is an established prognostic biomarker for aggressive HER2+ breast cancer (BC). Improving pCR rates may identify new therapies that improve survival. Pertuzumab (P) has established survival benefit in the metastatic setting, and received accelerated approval in the neoadjuvant setting when combined with trastuzumab (H) and docetaxel(D) as part of a complete treatment regimen for early breast cancer. We tested its ability, when combined with standard therapy (paclitaxel, T, and H) to improve pCR (ypT0ypN0) over TH in the adaptively randomized, phase II, I-SPY 2 neoadjuvant trial.

Methods: Enrolled patients (pts) had invasive BC ?2.5 cm in HER2-positive subsets. Pts were adaptively randomized to control (TH, qwk x 12) or THP (P, q3wk x 4) followed by doxorubicin/cyclophosphamide (AC) x 4 and surgery. To compare THP to TH we utilized all control pts accrued over the course of the trial, adjusting for potential differences due to time period treated, which were informed by the several other treatment arms that have been in the trial. Adaptive assignment to the experimental arms was based on current Bayesian probabilities of superiority over control. “Graduation” by signature and futility stopping were based upon Bayesian predictive probability of success in a 2-arm, N = 300 phase III randomized 1:1 trial of THP vs. TH with pCR endpoint.

Results: THP met the predictive probability criterion and graduated in 3 signatures: all HER2+, HER2+/HR+, and HER2+/HR- (See Table 1). Final accrual: 44 THP and 31 TH. Safety data will be shown.

Conclusions: I-SPY 2's standing platform trial efficiently evaluates agents in biomarker-defined pt subsets. THP -> AC substantially improves pCR rates over standard TH -> AC in all 3 HER2+ signatures, including HR+ and HR- subsets. APHINITY, a trial of adjuvant pertuzumab with a primary outcome of invasive disease-free survival, is ongoing. Table 1Signature*Estimated pCR Rate (95% probability interval)Signature*THPControl (TH)Probability THP Is Superior to ControlPredictive Probability of Success in Phase IIIHER2+54% (38%-70%)22% (5%-39%)99.8%96%HER2+/HR+44% (24%-63%)17% (0%-34%)99%91%HER2+/HR-74% (53%-95%)33% (6%-59%)99.8%98%*HR = Hormone Receptor

Citation Format: Meredith Buxton, Angela M. DeMichele, Stephen Chia, Laura van't Veer, Jo Chien, Anne Wallace, Henry Kaplan, Julie Lang, Douglas Yee, Claudine Isaacs, Stacy Moulder, Kathy Albain, Judy Boughey, Kathleen Kemmer, Barbara Haley, Susan Minton, Andres Forero, Rita Nanda, Anthony Elias, Larissa Korde, Rebecca Viscuzi, Hope Rugo, Richard Schwab, Fraser Symmans, Melissa Paoloni, Nola Hylton, Michael Hogarth, Julia Lyandres, Jane Perlmutter, Ashish Sanil, Christina Yau, Laura Esserman, Don Berry, I-SPY 2 TRIAL Investigators. Efficacy of pertuzumab/trastuzumab/paclitaxel over standard trastuzumab/paclitaxel therapy for HER2+ breast cancer: Results from the neoadjuvant I-SPY 2 TRIAL. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr CT106.

Abstract P2-05-05: Expression profiling of in vivo DCIS progression models identified BCL9 as a molecular driver of invasive progression

Introduction: There are an estimated 60,000 new cases of ductal carcinoma in situ (DCIS) each year. At present, it is not clear why some DCIS remain non-invasive for decades while others become invasive. A lack of understanding in DCIS pathobiology has led to overtreatment of more than half of DCIS patients. To identify factors that promote DCIS invasion, we have profiled the temporal molecular changes during DCIS transition to invasive ductal carcinoma (IDC) using two in vivo models, MIND (mouse-intraductal) and DCIS/IDC tandem lesions. These studies led to the identification of B cell lymphoma-9 as a potential molecular driver of early invasion. BCL9 is a newly found co-activator of Wnt-stimulated β-catenin-mediated transcription. BCL9 has been shown to promote progression of multiple myeloma and colon carcinoma. However its role in breast cancer progression had not been recognized.

Methods: Microarray and RNA sequencing were utilized to characterize the sequential and temporal changes in mRNA expression during DCIS invasive transition. BCL9 shRNA knockdown was performed to assess the role of BCL9 in in vivo invasion, EMT and canonical Wnt signaling. Immunofluorescence of 28 patient DCIS samples was used to assess a correlation between the expression of BCL9 and biomarkers of high risk DCIS. TCGA data was analyzed to assess the status of BCL9 gene alterations in 959 human breast cancers.

Results: Analysis of BCL9, by RNA and protein showed BCL9 up-regulation to be associated with DCIS transition to IDC. Analysis of patient DCIS revealed a significant correlation between high nuclear BCL9 and pathologic characteristics associated with DCIS recurrence: ER and PR negative, high nuclear grade, and high HER2. In vivo silencing of BCL9 resulted in the inhibition of DCIS invasion and reversal of epithelial-mesenchymal transition (EMT). Analysis of the TCGA data showed BCL9 gene to be altered in 26% of breast cancers. This is a significant alteration when compared to ERBB2 (19%) and ESR1 (8%). A significantly higher proportion of basal like invasive breast cancers showed BCL9 amplification.

Conclusion: BCL9 is a molecular driver of DCIS invasive progression and may predispose to the development of basal like invasive breast cancers. As such, BCL9 has the potential to serve as a biomarker of high risk DCIS and as a therapeutic target for prevention of IDC.

Citation Format: Behbod F, Elsarraj H, Hong Y, Valdez K, Chien J, Godwin A, Fields T. Expression profiling of in vivo DCIS progression models identified BCL9 as a molecular driver of invasive progression. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-05-05.

Abstract P3-06-25: MammaPrint High1/High2 risk class as a biomarker of response to veliparib/carboplatin plus standard neoadjuvant therapy for breast cancer in the I-SPY 2 TRIAL

Background: Further stratification of the 70-gene MammaPrintTM signature into ‘high’ and ‘ultra-high’ risk groups may help predict chemo-sensitivity. In I-SPY 2, patients were classified as MammaPrint High1 (MP1) or MammaPrint (ultra) High2 (MP2), with MP2 defined as MP_score <-0.154. MP1/MP2 classification was added to HR and Her2 to define the cancer subtypes used in the I-SPY 2 adaptive randomization engine. HER2- patients were randomized to receive standard chemotherapy or the oral PARP inhibitor veliparib in combination with carboplatin (V/C) and chemotherapy. V/C graduated in the triple-negative (TN) signature, where MP2 was not an eligible signature for graduation. Here, we assess the performance of MP1/MP2 class as a specific biomarker of response to V/C.

Methods:115 HER2- patients (V/C: 71 and concurrent controls: 44) were considered in this analysis. We assess association between MP1/MP2 and response in the V/C and control arms alone using Fisher’s exact test, and relative performance between arms (biomarker x treatment interaction, likelihood ratio p < 0.05) using a logistic model. This analysis is also performed adjusting for HR status as a covariate. To assess MP1/MP2 in the context of the graduating signature, we added the MP2 patients to the graduating TN subset and evaluated the treatment effect in this ‘biomarker-positive’ group. Our study is exploratory with no claims for generalizability of the data. Statistical calculations are descriptive (e.g. p-values are measures of distance with no inferential content). This analysis does not adjust for multiplicities of other biomarkers in the trial but outside this study.

Results: In the V/C arm vs. concurrent controls, there were 66 MP1 (V/C: 32, Control: 34) and 49 MP2 patients (V/C: 39, Control: 10), 78% of which are TN. The distribution of pCR rates among MP1/MP2 dichotomized groups are summarized in Table 1.

V/C (n=71)Control (n=44)MP1 (n=32)MP2 (n=39)MP1 (n=34)MP2 (n=10)TN (n=59)3 / 819 / 303 / 132 / 8HR+HER2- (n=56)1 / 244 / 94 / 210 / 2

The OR between MP1/MP2 risk groups for predicting pCR is 9.71 in the V/C arm (p=6.63E-05), in comparison to an OR of 0.97 in the control arm (p=1). There is a significant biomarker x treatment interaction (p=0.023), which remains upon adjusting for HR status (p= 0.028). Based on the I-SPY 2 Bayesian model, a Phase III trial with 300 MP2 patients has a 95% predictive probability of success. When the MP2 patients are added to the graduating TN subset, the OR associated with V/C is 4.36, which is comparable to that of the TN signature (OR: 4.29), while increasing the prevalence of biomarker-positive patients by ∼10%.

Conclusion: In our exploratory analysis, MP2 suggests higher sensitivity to V/C combination therapy relative to controls. This observation has prompted an investigation into the biological mechanisms distinguishing the MP1/MP2 subtype that may account for this specificity.

Citation Format: Denise M Wolf, Christina Yau, Ashish Sanil, Jo Chien, Anne Wallace, Angela DeMichele, Hank Kaplan, Doug Yee, Claudine Isaacs, Kathy Albain, Rebecca Viscuzi, Judy Boughey, Stacey Moulder, Steven Chui, Qamar Khan, Toncred Styblo, Kirsten Edmiston, Donald Northfelt, Anthony Elias, Barbara Haley, Debu Tripathy, Lamorna Brown-Swigart, Susan Flynn, Gillian Hirst, Meredith Buxton, Nola Hylton, Melissa Paoloni, Fraser Symmans, Laura Esserman, Don Berry, Hope Rugo, Olufunmilayo I. Olopade, Laura van 't Veer. MammaPrint High1/High2 risk class as a biomarker of response to veliparib/carboplatin plus standard neoadjuvant therapy for breast cancer in the I-SPY 2 TRIAL [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-25.

Abstract P3-06-29: MammaPrint High1/High2 risk class as a biomarker of response to neratinib plus standard neoadjuvant therapy for breast cancer in the I-SPY 2 TRIAL

Background: Further stratification of the 70-gene MammaPrintTM signature into ‘high’ and ‘ultra-high’ risk groups may help predict chemo-sensitivity. In I-SPY 2, patients were classified as MammaPrint High1 (MP1) or MammaPrint (ultra) High2 (MP2), with MP2 defined as MP_score <-0.154. MP1/MP2 classification was added to HR and HER2 to define the cancer subtypes used in the I-SPY 2 adaptive randomization engine. Neratinib (N), one of the experimental agents evaluated in I-SPY 2, graduated in the HR-HER2+ signature. All patients received at least standard chemotherapy (paclitaxel followed by doxorubicin/cyclophosphamide; T->AC). HER2- patients were randomized to receive N+T- >AC vs. T->AC. For HER2+ patients, neratinib was administered in place of trastuzumab (N+T->AC vs. H+T->AC). Here, we assess the performance of MP1/MP2 class as a specific biomarker of neratinib response.

Methods: 115 patients in the neratinib arm and 76 concurrently randomized controls had Agilent 44K microarrays and pCR data available for analysis. We assess association between MP1/MP2 and response in the neratinib and control arms alone using Fisher’s exact test, and relative performance between arms (biomarker x treatment interaction, likelihood ratio p < 0.05) using a logistic model. This analysis is also performed adjusting for HR status as a covariate, and in receptor subsets. Our study is exploratory with no claims for generalizability of the data. Statistical calculations are descriptive (e.g. p-values are measures of distance with no inferential content). Our analyses do not adjust for multiplicities of other biomarkers in the trial but outside this study.

Results: There are 133 MP1 patients (neratinib: 74, Control: 59) and 58 MP2 patients (neratinib: 41, Control: 17), 84% (49) of which are Her2-. The distribution of pCR rates among MP1/MP2 dichotomized groups are summarized in Table 1.

 Neratinib (n=115)Control (n=76)MP1 (n=74)MP2 (n=41)MP1 (n=59)MP2 (n=17)HER2- (n=105)0 / 1715 / 337 / 395 / 16HER2+ (n=86)22 / 574 / 85 / 200 / 1

MP2, one of the 10 eligible signatures, did not meet the graduation threshold; and MP1/MP2 did not show a significant biomarker x treatment interaction (OR in neratinib relative to control arm = 1.25). The MP1/MP2 x treatment interaction remains non-significant after adjustment for HR and HER2 status (p=0.54). In HER2- patients receiving neratinib, 45% (15/33) of MP2 patients achieved a pCR, compared to 0% (0/17) of MP1 patients. In the HER2- controls, there is a 31% pCR rate in MP2 (5/16) vs. 18% in MP1 (7/39) patients (OR=2.14). This difference in performance between treatment arms appears significant (p=0.041). 90% of HER2+ patients are MP1, thus MP1/MP2 status x treatment interaction within the HER2+ subtype cannot be evaluated.

Conclusion: Within the I-SPY 2 population as a whole, MP1/MP2 stratification does not appear to be a specific biomarker of response to neratinib relative to the control arm. The number of HER2- patients is small and precludes any definitive conclusion, but these data motivate further investigation of the biological mechanisms distinguishing MP1 from MP2 to better understand chemotherapy and/or neratanib responsiveness.

Citation Format: Christina Yau, Denise M Wolf, Ashish Sanil, Jo Chien, Anne Wallace, Judy Boughey, Doug Yee, Debu Tripathy, Angela DeMichele, Rita Nanda, Steven Chiu, Claudine Isaacs, Kathy Albain, Hank Kaplan, Stacey Moulder, Rebecca Viscusi, Donald Northfelt, Kirsten Edmiston, Anthony Elias, Toncred Styblo, Barbara Haley, Lamorna Brown-Swigart, Susan Flynn, Gillian L Hirst, Meredith Buxton, Nola Hylton, Melissa Paoloni, W Fraser Symmans, Laura Esserman, Don Berry, Minetta C Liu, John W Park, Laura van 't Veer. MammaPrint High1/High2 risk class as a biomarker of response to neratinib plus standard neoadjuvant therapy for breast cancer in the I-SPY 2 TRIAL [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P3-06-29.

Clinical characteristics of ovarian cancer classified by BRCA1, BRCA2, and RAD51C status

We evaluated homologous recombination deficient (HRD) phenotypes in epithelial ovarian cancer (EOC) considering BRCA1, BRCA2, and RAD51C in a large well-annotated patient set. We evaluated EOC patients for germline deleterious mutations (n = 899), somatic mutations (n = 279) and epigenetic alterations (n = 482) in these genes using NGS and genome-wide methylation arrays. Deleterious germline mutations were identified in 32 (3.6%) patients for BRCA1, in 28 (3.1%) for BRCA2 and in 26 (2.9%) for RAD51C. Ten somatically sequenced patients had deleterious alterations, six (2.1%) in BRCA1 and four (1.4%) in BRCA2. Fifty two patients (10.8%) had methylated BRCA1 or RAD51C. HRD patients with germline or somatic alterations in any gene were more likely to be high grade serous, have an earlier diagnosis age and have ovarian and/or breast cancer family history. The HRD phenotype was most common in high grade serous EOC. Identification of EOC patients with an HRD phenotype may help tailor specific therapies.

An unusual complication of dengue infection

We present an unusual complication of dengue infection resulting in postviral phrenic neuropathy and diaphragmatic paralysis in a 34-year-old man. There is a paucity of literature on this condition, with postviral neuropathies previously reported to be associated commonly with herpes zoster, poliovirus, and rarely, West Nile virus and human immunodeficiency virus infections. To our knowledge, this is the first reported case of flavivirus causing isolated postviral phrenic neuropathy and diaphragmatic paralysis.

A role for candidate tumor-suppressor gene TCEAL7 in the regulation of c-Myc activity, cyclin D1 levels and cellular transformation

The pathophysiological mechanisms that drive the development and progression of epithelial ovarian cancer remain obscure. Recently, we identified TCEAL7 as a transcriptional regulatory protein often downregulated in epithelial ovarian cancer. However, the biological significance of such downregulation in cancer is not currently known. Here, we show that TCEAL7 is downregulated frequently in many human cancers and that in immortalized human ovarian epithelial cells this event promotes anchorage-independent cell growth. Mechanistic investigations revealed that TCEAL7 associates with cyclin D1 promoter containing Myc E-box sequence and transcriptionally represses cyclin D1 expression. Moreover, downregulation of TCEAL7 promotes DNA-binding activity of Myc-Max, and upregulates the promoter activity of c-Myc-target gene, ornithine decarboxylase (ODC), whereas enhanced expression of TCEAL7 inhibits Myc-induced promoter activity of ODC. Our findings suggest that TCEAL7 may restrict ovarian epithelial cell transformation by limiting Myc activity. These results also suggest a potential, alternative mechanism by which c-Myc activity may be deregulated in cancer by the downregulation of TCEAL7.

Epigenetic silencing of HSulf-1 in ovarian cancer:implications in chemoresistance

To investigate the mechanism by which HSulf-1 expression is downregulated in ovarian cancer, DNA methylation and histone acetylation of HSulf-1 was analysed in ovarian cancer cell lines and primary tumors. Treatment of OV207 and SKOV3 by 5-aza-2'-deoxycytidine resulted in increased transcription of HSulf-1. Sequence analysis of bisulfite-modified genomic DNA from ovarian cell lines and primary tumors without HSulf-1 expression revealed an increase in the frequency of methylation of 12 CpG sites in exon 1A. Chromatin immunoprecipitation assays showed an increase in histone H3 methylation in cell lines without HSulf-1 expression. To assess the significance of HSulf-1 downregulation in ovarian cancer, OV167 and OV202 cells were transfected with HSulf-1 siRNA. Downregulation of HSulf-1 expression in OV167 and OV202 cells lead to an attenuation of cisplatin-induced cytotoxicity. Moreover, patients with ovarian tumors expressing higher levels of HSulf-1 showed a 90% response rate (27/30) to chemotherapy compared to a response rate of 63% (19/30) in those with weak or moderate levels (P=0.0146, chi(2) test). Collectively, these data indicate that HSulf-1 is epigenetically silenced in ovarian cancer and that epigenetic therapy targeting HSulf-1 might sensitize ovarian tumors to conventional first-line therapies.

HtrA1 expression as a predictive factor of response to cisplatin-based regimen in patients with advanced gastric cancer

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Background: Human HtrA1 is a member of the HtrA (High temperature requirement) family of serine proteases. Recent reports suggest that htrA1 plays a protective role in varous malignancies due to its tumour suppressive properties. This study was performed to estimate HtrA1 expression as a predictor of the response to chemotherapy of patients with gastric cancer. Methods: HtrA1 was measured immunohistochemically on archival specimens of primary gastric cancer from 51 patients treated consecutively at our institution with a weekly chemotherapy including cisplatin 40 mg/m2, epirubicin 35 mg/m2, 6S-leucovorin 100 mg/m2, 5-fluorouracil 500 mg/m2, with the support of filgrastim 5 μg/Kg from the day 2 to 7 (PELF regimen), or cisplatin 40 mg/m2, epirubicin 35 mg/m2, 6S-leucovorin 100 mg/m2, 5-fluorouracil 500 mg/m2 (PLF regimen). Response to chemotherapy was assessed after 8 weekly treatments according to the WHO criteria. Results: our population consisted of M/F 32/19; median age 64 years (range, 46–79). The prevalent metastatic sites were liver (17 pts), peritoneum (13 pts), lymph nodes (21 pts), locoregional disease (16 pts); 31/16/4 pts had 1/2/3 or more sites of disease. 23 pts had a low expression of HtrA1 (0/1+) versus 28 patients with higher expression (2+). Of the total 51 patients, there were 28 responders: 8 showing complete response (CR) and 20, partial response (PR). Of the 28 responders, 20 were in the higher HtrA1 staining group (2+), while of the 23 non-responders, 15 were in the higher HtrA1 staining group (0/1+). A statistically significant correlation between HtrA1 expression (HtrA1 2+ versus HtrA1 0/1+) and the clinical response was observed (response rate in patients with 2+ and 0/1+: 71.4% versus 34.8%, P < 0.01, respectively). Interestingly, among 16 pts with locoregional disease (stomach, gastric bed, anastomosis), 1/6 pts had HtrA1 1+ expression compared to 8/10 pts with HtrA1 2+ (17% versus 80%, respectively; p = 0.025). Conclusions: The immunohistochemical identification of HtrA1 on the primary gastric cancer prior to chemotherapy may be a useful predictor for choice of potentially responders to a cisplatin-based chemotherapy.

No significant financial relationships to disclose.

Smoking enhances absorption of insulin but reduces glucodynamic effects in individuals using the Lilly-Dura inhaled insulin system

AIM

To quantify the pharmacokinetic (PK) and glucodynamic (GD) impact of smoking on inhaled and subcutaneous (SC) insulin administration in healthy subjects.

METHODS

This study employed the euglycemic clamp procedure in a four-period, four-way randomized crossover design. Eight smoking and eight non-smoking healthy males were given SC insulin on two occasions and human insulin inhalation powder (HIIP) on two other occasions.

RESULTS

Smokers exhibited greater insulin exposure (AUC(0-t')) than non-smokers, following both routes of insulin administration (HIIP, P = 0.003, 58% increase; SC, P = 0.006, 24% increase). The maximum insulin concentration (C(max)) following HIIP was greater in smokers by 172% (P = 0.001) compared with non-smokers. The glucodynamic effects were greater in smokers following HIIP, consistent with the insulin concentration difference observed. However, maximum glucose response (R(max)) following SC was decreased by 36% (P = 0.001) and obtained later [time of maximum glucose response (TR(max)); P < 0.001] in smokers than in non-smokers. Smokers appeared less sensitive to insulin [total glucose infused during the clamp procedure normalised by total insulin exposure (G(tot))/AUC(0-t')] than non-smokers following both SC (P = 0.001) and inhaled (P = 0.011) routes of administration.

CONCLUSION

Smokers had substantially increased peak HIIP insulin concentration, but the glucodynamic effect was partially offset, most likely because of increased insulin resistance.

Estimating dose equivalence for new routes of drug administration

For patient's convenience, dose administration of insulin via oral inhalation is often considered as an alternative to subcutaneous administration. An important statistical problem is to estimate dose equivalence, which is the amount of drug needed to be delivered by inhalation to generate an equivalent pharmacokinetic (PK) response produced by a therapeutic dose of subcutaneous insulin. Because of high intersubject variability, a crossover design clinical trial is typically used where data from both routes of administration are obtained from the same subject. A linear mixed effects model is proposed to describe the relationship between AK response and insulin dose for the two routes of administration. Estimation of dose equivalence in this setting has not been discussed in the statistical literature. Several competing methods for estimating dose equivalence are proposed and contrasted. A formula for calculating an approximate sample size necessary to estimate dose equivalence with a desired precision for the new route of administration is also provided.

Inhaled micronized crystalline human insulin using a dry powder inhaler: dose-response and time-action profiles

AIM

The aim of this euglycaemic glucose clamp study was to investigate the pharmacokinetics, glucodynamics, safety and tolerability of micronized crystalline human insulin inhalation powder delivered by a Spiros dry powder inhaler system in healthy volunteers.

METHODS

Thirteen healthy, non-smoking, male and female volunteers [age 30 +/- 7 years; BMI 23.5 +/- 2.7 kg/m(2); (mean +/- sd)] with normal pulmonary function participated in an open-label, randomised, 6-period crossover trial. Each volunteer received four single doses of inhaled insulin (60, 90, 120, 150 U) on separate occasions. For comparison, each volunteer also received two of three possible doses of subcutaneous (s.c.) injected regular human insulin (8, 14, or 20 U).

RESULTS

Serum immunoreactive insulin following inhalation of insulin peaked an average of 60 min earlier compared with s.c. injected insulin (P < 0.0001). Following inhalation, the time to maximum glucose infusion rate occurred an average of 70 min earlier than with s.c. insulin: 187, 129, 161 and 162 min vs. 227, 241 and 241 min (P < 0.0001). The dose-response relationships for serum insulin pharmacokinetics and glucodynamics were linear for both inhaled and s.c. insulin. Relative bioavailability (based on serum insulin levels) ranged from 11.5 to 12.2% for the four doses of inhaled insulin and relative biopotency (based on glucose infusion rates) was 10.0 to 16.5%, respectively. Dosing was well tolerated by all volunteers.

CONCLUSION

This study demonstrates that inhalation of human insulin via a dry powder inhaler system provides a promising alternative route for administration of insulin.

Calcitonin is expressed in gonadotropes of the anterior pituitary gland: its possible role in paracrine regulation of lactotrope function

Previous studies from this laboratory have shown that salmon (S) calcitonin (CT)-like immunoreactive peptide (CTI) is synthesized and secreted by the anterior pituitary (AP) gland. These studies also co-localized CTI to gonadotropes, and demonstrated that SCT is a potent inhibitor of lactotrope function. However, the molecular structure of putative gonadotrope-derived CTI that inhibits lactotrope function has not been defined. The present studies cloned CT cDNA (pit-CT cDNA) from a mouse gonadotrope L beta T2 cell line using RT-PCR and rapid amplification of cDNA ends (RACE) techniques. Alignment of nucleotide sequences of pit-CT and mouse CT revealed greater than 99% homology between the sequences. The pit-CT cDNA was ligated into a mammalian expression vector, and the construct was transfected into L beta T2 cells. Two stable transfectant cell lines (CT.U6/A and B) were obtained by selection in G418. Subsequent S1-nuclease protection assay and immunocytochemistry results have shown that: (1) pit-CT peptide expressed by CT.U6 cell lines immunoreacted with GCT1-anti-SCT serum; (2) secretions of CT.U6 cells inhibited prolactin (PRL) release, PRL mRNA abundance and DNA synthesis of PRL-secreting GGH3 cells; and (3) CT.U6-induced inhibition was abolished by GCT1-anti-SCT serum. The studies also generated a riboprobe from the cloned pit-CT cDNA, and localized CT mRNA expression in gonadotropes of rat AP gland by in situ hybridization histochemistry. These results demonstrate that pit-CT mRNA is closely homologous to mouse CT mRNA; it is expressed by gonadotropes of the rat AP gland, and the peptide may significantly affect lactotrope function by inhibiting PRL release and cell proliferation.

Calcitonin is a prostate epithelium-derived growth stimulatory peptide

Locally secreted growth factors and neuropeptides may play an important role in sustaining the growth of hormone-independent prostate cancer. Our previous studies have shown that calcitonin-like immunoreactive peptide (CTI) is secreted by primary prostate cells in culture, and its secretion from malignant prostate cells is significantly higher than benign cells. Exogenously added calcitonin (CT) induces DNA synthesis in serum-starved prostate cancer LNCaP and PC-3M cells. Present studies extended these findings by cloning cDNAs for CT and CT receptor (CT-R) from prostate cancer cells and studying the expression of CT and CT-R mRNA in prostate cancer cell lines and primary prostate tumor specimens. The results have shown that PC-3 cells expressed CT, and not CT-R, mRNA, whereas CT-R, but not CT, mRNA was expressed by LNCaP cells. Conditioned media from PC-3 cells induced DNA synthesis of LNCaP cells, and this mitogenic response was abolished by anti-CT serum. Highly aggressive PC-3M cells co-expressed CT and CT-R mRNAs. CT also induced a twofold increase in DNA synthesis of primary prostate cells and anti-CT serum caused a 56% decline. In-situ hybridization histochemistry of archival prostate specimens has selectively localized CT and CT-R mRNA in basal epithelium of benign and low grade PC specimens, and these mRNAs were not detected in either luminal epithelium or stroma. In contrast, CT and CT-R mRNA were detected throughout the luminal epithelium of moderate and high-grade PC specimens. Most epithelial cells of low and moderately differentiated tumors expressed either CT or CT-R mRNA, suggesting that CT may serve as a paracrine factor. In contrast, CT and CT-R mRNAs were co-expressed by most tumor cells in advanced PC specimens. The cells expressing CT-R mRNA in primary tumors also co-expressed PCNA. These results, when combined with mitogenic actions of CT on primary prostate cells as well as PC cell lines, strongly support the role for CT in sustaining the growth of cancer cells.

Role of stimulatory guanine nucleotide binding protein (GSalpha) in proliferation of PC-3M prostate cancer cells

Previous studies have shown that calcitonin-like immunoreactive substances are secreted by primary prostate cells. Furthermore, exogenously added calcitonin stimulates proliferation of androgen-responsive LnCaP cells. To examine the possible effect of calcitonin on growth of invasive prostate cancer cells, we tested its effects on proliferation of PC-3M cells. Calcitonin stimulated DNA synthesis of PC-3M cells in a dose-dependent fashion, and also stimulated adenylyl cyclase and protein kinase C activities. To further delineate the role of these signaling cascades in proliferation of PC-3M prostate cancer cells, we selectively activated these pathways by transfecting cDNAs expressing constitutively active forms of either Gsalpha (Gsalpha-QL) or Gqalpha (Gqalpha-QL). cDNAs expressing wild-type forms of G-proteins (Gsalpha-WT and Gqalpha-WT) were used as vehicle controls. Gqalpha-QL transfectants exhibited growth inhibition and terminal differentiation. Those expressing Gsalpha-QL exhibited a dramatic increase in growth rate. Gsalpha-QL transfectants displayed an almost 3-fold increase in [3H]-thymidine incorporation and over a 4-fold increase in growth rate when compared with parental PC-3M cells or those expressing wild-type Gsalpha (Gsalpha-WT). The growth-promoting action of Gsalpha-QL could not be mimicked by either 8-bromo cAMP or forskolin. However, nifedipine, a calcium channel antagonist, potently and selectively inhibited DNA synthesis in Gsalpha-QL transfectants. These results suggest that the growth-promoting actions of Gsalpha on PC-3M cells may be mediated by nifedipine-sensitive proliferative events.

Calcitonin inhibits anterior pituitary cell proliferation in the adult female rats

Previous studies have shown that CT-like immunoreactive peptide(s) (pit-CT) is synthesized by the anterior pituitary (AP) gland, and exogenously added salmon(s) CT inhibits PRL release and PRL gene transcription in cultured AP cells. Anti-sCT serum, which immunoreacts with pit-CT, stimulates PRL secretion, suggesting pit-CT is a physiologically relevant PRL-inhibiting hormone. Using proliferating cell nuclear antigen (PCNA) staining and 5-bromo-2'deoxyuridine (BrdU) incorporation into newly replicated DNA, the effect of calcitonin (CT) on cellular proliferation in the rat anterior pituitary gland (AP) was examined. CT significantly attenuated PCNA-immunopositive as well as BrdU-positive AP cell populations in dispersed rat AP cells. A second series of experiments tested the effects of CT on AP cell proliferation in vivo. OVX + E2 rats were injected with 200 microg CT (iv), the rats killed at various time points, and the APs were processed for BrdU staining. CT inhibited BrdU incorporation at all time points up to 15 h after the injection, and this inhibitory effect was reversed at later time points. The effect of CT was concentration dependent, and a maximal inhibition was observed 10 h after the CT injection. Subsequent experiments identified CT-responsive AP cell populations using double immunofluorescence for BrdU and either PRL or FSH. The number of BrdU-labeled lactotropes in the AP gland declined by 74% in the CT-treated rats. Neutralization of endogenous pit-CT by passive immunization with anti-sCT serum caused a 2-fold increase in AP cell proliferation. These results suggest an important role for the endogenous pit-CT in regulation of lactotrope population of the AP gland.

Constitutive activation of stimulatory guanine nucleotide binding protein (G(S)alphaQL)-mediated signaling increases invasiveness and tumorigenicity of PC-3M prostate cancer cells

An abnormal stimulation of cAMP signaling cascade has been implicated in various human carcinomas. Since the agents activating G(S)alpha-mediated signaling pathways have been shown to increase in vitro proliferation of prostate cancer cells, present studies examined the G(S)alpha-mediated signaling in tumorigenicity and invasiveness of PC-3M prostate cancer cells. PC-3M cells were stably transfected with plasmids containing either wild type (G(S)alpha-WT) or constitutively active (gsp mutant of G(S)alpha or G(S)alpha-QL) cDNAs. The stable transfectants were then tested for: (1) colony formation in soft agar; (2) cell migration and penetration of basement matrix in an in vitro invasion assay; and (3) the ability to form tumors and metastases in nude mice. PC-3M cells expressing G(S)alpha-QL protein displayed 15-fold increase in their ability to migrate and penetrate the basement membrane as compared to parental PC-3M cells or those expressing G(S)alpha-WT. G(S)alpha-QL transfectants also displayed a dramatically greater rate of growth in soft agar, and greater tumorigenicity and metastasis forming ability when orthotopically implanted in nude mice. All mice receiving PC-3M cells produced primary tumors within 5 weeks after implantation. However, the cells expressing G(S)alpha-QL displayed a significantly faster tumor growth as assessed by prostate weight (greater than 20-fold as compared to PC-3M cells), and produced metastases in kidneys, lymph nodes, blood vessels, bowel mesentery and intestine. Interestingly, expression of G(S)alpha-WT reduced the ability of PC-3M cells to form tumors in nude mice. These results suggest that persistent activation of G(S)alpha-mediated signaling cascade can dramatically accelerate tumorigenesis and metastasizing ability of prostate cancer cells.

Observation of a new nonfluorescent malondialdehyde-acetaldehyde-protein adduct by 13C NMR spectroscopy

It has been shown that malondialdehyde (MDA) and acetaldehyde react with proteins via the epsilon-amino group of a lysine residue to yield hybrid MDA-acetaldehyde (MAA)-protein adducts. The structure of one MAA adduct has been confirmed to be 4-methyl-1, 4-dihydropyridine-3,5-dicarbaldehyde (3). In this study, 13C NMR spectroscopy was used to identify the structure of a second MAA adduct as 2-formyl-3-(alkylamino)butanal (4). Isotopically labeled [1-13C]acetaldehyde was reacted with MDA and the protein, bovine serum albumin, under a variety of conditions, and the reactions were monitored at various time intervals by 13C NMR. In each experiment, new signals grew in at 50 and 22 ppm. By comparison to model compounds, the signals at 50 ppm correspond to a 2-formyl-3-(alkylamino)butanal adduct and the signals at 22 ppm correspond to the known 1,4-dihydropyridine-3,5-dicarbaldehyde adduct. Similar results were found when the BSA was replaced with polylysine. Overall, it appears that MAA-protein adducts are composed of two major products, 3 and 4.

Guardian: an experimental system for intelligent ICU monitoring

We are developing an intelligent agent for patient monitoring named Guardian. It is applied to the post-operative monitoring and therapy management of cardiac surgery patients. Even though Guardian is an experimental system so far, we anticipate that in the short term it will be integrated with existing ICU information systems and critically evaluated on simulated patient cases. In evaluating the system, we aim to demonstrate that human-machine cooperation in information overload situations can improve the work environment of clinicians, improve health care delivery, and ultimately reduce health-care costs.

Cytomegalovirus pneumonia in allogeneic bone marrow transplantation. An immunopathologic process?

Recent literature suggests that CMV pneumonia is an immunopathologic process. This case report summarizes the clinical course of a patient which supports this hypothesis. The patient is the recipient of an allogeneic BMT who recovered from an episode of CMV pneumonia that occurred about two months after the transplant. Despite recovery from the viral infection, follow-up BALs revealed persistent lymphocytosis in an apparent asymptomatic patient. He subsequently developed BOOP about four months after the initial CMV infection. These observations suggest that the viral infection may have resulted in the activation of the host's cell-mediated response and provides evidence to support the hypothesis that CMV pneumonia is an immune-mediated process.