A Phase 2 Trial of Primary Tumor Stereotactic Body Radiation Therapy Boost Before Concurrent Chemoradiation for Locally Advanced Non-Small Cell Lung Cancer

PURPOSE

Primary tumor failure is common in patients treated with chemoradiation (CRT) for locally advanced NSCLC (LA-NSCLC). Stereotactic body radiation therapy (SBRT) yields high rates of primary tumor control (PTC) in early-stage NSCLC. This trial tested an SBRT boost to the primary tumor before the start of CRT to improve PTC.

METHODS AND MATERIALS

Patients with LA-NSCLC received an SBRT boost in 2 fractions (central location 12 Gy, peripheral location 16 Gy) to the primary tumor, followed by standard CRT (60 Gy in 30 fractions). The primary objective was PTC rate at 1 year, and the hypothesis was that the 1-year PTC rate would be ≥90%. Secondary objectives included objective response rate, regional and distant control, disease-free survival (DFS), and overall survival (OS). Correlative studies included functional magnetic resonance imaging and blood-based miRNA analysis.

RESULTS

The study enrolled 21 patients (10 men and 11 women); the median age was 62 years (range, 52-78). The median pretreatment primary tumor size was 5.0 cm (range, 1.0-8.3). The most common nonhematologic toxicities were pneumonitis, fatigue, esophagitis/dysphagia, dyspnea, and cough. Only 1 treatment-related grade 4 nonhematologic toxicity occurred (respiratory failure/radiation pneumonitis), and no grade 5 toxicities occurred. The objective response rate at 3 and 6 months was 72.7% and 80.0%, respectively, and PTC at 1 and 2 years was 100% and 92.3%, respectively. The 2-year regional and distant control rates were 81.6% and 70.3%, respectively. Disease-free survival and overall survival at 2 years were 46.1% and 50.3%, respectively, and median survival was 37.8 months. Functional magnetic resonance imaging detected a mean relative decrease in blood oxygenation level-dependent signal of -87.1% (P = .05), and miR.142.3p was correlated with increased risk of grade ≥3 pulmonary toxicity (P = .01).

CONCLUSIONS

Dose escalation to the primary tumor using upfront SBRT appears feasible and safe. PTC was high and other oncologic endpoints compared favorably to standard treatment. Functional magnetic resonance imaging suggested changes in oxygenation with the first SBRT boost dose, and miR.142.3p was correlated with pulmonary toxicity.

A cancer disparities curriculum in a hematology/oncology fellowship program

BACKGROUND

After George Floyd's murder in 2020, the Center for Disease Control and Prevention (CDC) called systemic racism a public health crisis. This health crisis is connected to the already-documented racial and socioeconomic disparities in cancer care. Ensuring hematologists and oncologists are aware of these disparities through their medical education can help to address these disparities.

METHODS

The authors implemented a healthcare disparities-focused curriculum in a Hematology/Oncology fellowship program during the 2020-2021 academic year at The Ohio State University Hematology/Oncology Fellowship Program. They implemented a pre- and post- survey to evaluate the efficacy of the program.

RESULTS

Fifteen fellows completed the pre-curriculum survey and 14 completed the post-survey. Before the curriculum, 12 fellows (80%) noted a "Fair" or "Good" understanding of healthcare disparities, and 6 (40%) had a "Fair" understanding of disparities in clinical trials and access to novel therapies. Fourteen fellows (93.3%) had not previously participated in a research project focused on identifying or overcoming healthcare disparities. After the curriculum, 12 (85%) fellows strongly agreed or agreed that the information presented in the curriculum was useful for training as a hematologist/oncologist. Twelve fellows (85%) noted "Agree" or "Strongly Agree" that the information presented was relevant to their practice. Eleven fellows (92%) noted that they plan to incorporate healthcare disparities into a future research or clinical project. The majority of fellows, 11 (79%) recommended that the fellowship program continue to have a formal health disparities curriculum in the future.

DISCUSSION/CONCLUSION

There is utility in incorporating cancer disparities education into a hematology/oncology academic curriculum. We recommend further analysis of such curricula to improve fellowship education and patient outcomes with these interventions.

Immune checkpoint inhibitor-related thrombocytopenia: incidence, risk factors and effect on survival

INTRODUCTION

Immune checkpoint inhibitors (ICI) are associated with unique immune-related adverse events (irAEs). Immune-related thrombocytopenia (irTCP) is an understudied and poorly understood toxicity; little data are available regarding either risk of irTCP or the effect of irTCP on clinical outcomes of patients treated with ICI.

METHODS

We conducted a retrospective review of sequential cancer patients treated with ICI between 2011 and 2017 at our institution. All patients who received ICI alone or in combination with other systemic therapy in any line of treatment were included; those with thrombocytopenia ≥ grade 3 at baseline were excluded. We calculated the incidence of ≥ grade 3 irTCP and overall survival (OS). Patient factors associated with irTCP were assessed.

RESULTS

We identified 1,038 patients that met eligibility criteria. Overall, 89 (8.6%) patients developed grade ≥ 3 thrombocytopenia; eighteen were attributed to ICI (1.73% overall). Patients who developed grade ≥ 3 irTCP had worse overall survival compared to those whose thrombocytopenia was unrelated to ICI (4.17 vs. 10.8 month; HR. 1.94, 95% CI 1.13, 3.33; log-rank p = 0.0164). Patients with grade ≥ 3 irTCP also had worse survival compared to those without thrombocytopenia (4.17 vs. 13.31 months; HR 2.22, 95% CI 1.36, 3.62; log-rank p = 0.001). The incidence of irTCP appeared lowest among those treated with PD-1/L1 monotherapy (p = 0.059) and was not associated with cancer type, smoking status, age, gender, race, or line of therapy.

CONCLUSIONS

Unlike other irAEs, we found that irTCP was associated with worse overall survival. The incidence of irTCP appeared lowest among those treated with PD-1/L1 monotherapy.

Abstract PO-003: CRESTONE – Clinical study of response to seribantumab in tumors with neuregulin-1 (NRG1) Fusions – A phase 2 study of the anti-HER3 mAb for advanced or metastatic solid tumors (NCT04383210)

Background: NRG1 (Neuregulin-1) gene fusions are rare oncogenic drivers found in 0.2% of solid tumors, including lung, pancreatic, gallbladder, breast, ovarian, colorectal, neuroendocrine, and sarcomas. NRG1 is the predominant ligand of HER3 and to a lesser extent HER4. NRG1 fusion proteins retaining an active EGF-like domain drive tumorigenesis and proliferation through aberrant HER3 activation. Importantly, NRG1 fusions are often mutually exclusive with other known driver alterations. NRG1 fusions have been correlated with worse overall and disease-free survival and poor response to treatment with standard therapies including chemotherapy, PD-(L)1 checkpoint inhibitors and combinations of these agents. Inhibition of HER3 and its dimerization partners represents a rational and novel therapeutic approach for tumors harboring an NRG1 fusion supported by case studies of clinical responses to anti-HER3 antibodies or pan-ERBB (tyrosine kinase inhibitors) TKIs like afatinib. Seribantumab is a fully human IgG2 mAb against HER3 uniquely able to inhibit NRG1-dependent activation of HER3, HER3-HER2 dimerization, and downstream signaling through the PI3K/AKT and MAPK pathways. The clinical safety profile of seribantumab has been well characterized through prior monotherapy and combination studies in over 800 patients. Methods: CRESTONE is an open label, multicenter Phase 2 basket trial of seribantumab in adult patients with NRG1 fusion-positive locally advanced or metastatic solid tumors who have progressed on or are nonresponsive to available therapies. The trial will enroll at least 75 previously treated patients across three cohorts. Cohort 1 (N=55) will include patients who have not received prior treatment with any ERBB targeted therapy. Cohort 2 (up to N=10) will include patients who have progressed after prior treatment which includes ERBB targeted therapy. Cohort 3 (up to N=10) will include patients harboring NRG1 fusions without an EGF-like binding domain. NRG1 fusion status for enrollment will be determined through a local CLIA or similarly accredited molecular assay. NRG1 fusion status for patients in Cohort 1 will be centrally confirmed using an RNA-based NGS assay. This study will evaluate a novel dosing regimen of weekly induction, biweekly consolidation, and Q3W maintenance designed to rapidly achieve steady state levels, optimize exposure, and deliver maximal NRG1 inhibition. The primary endpoint is ORR per RECIST v1.1 by independent radiologic review. Secondary endpoints include duration of response (DoR), safety, PFS, OS, and overall clinical benefit rate. An interim analysis is planned following enrollment of 20 patients in Cohort 1. CRESTONE is open and accruing patients in the United States. Clinical trial information: NCT04383210.

Citation Format: Johanna C. Bendell, Kian-Huat Lim, Mark E. Burkard, Jessica J. Lin, Young Kwang Chae, Mark A. Socinski, Gazala Khan, Karen L. Reckamp, Shawn Leland, Douglas Plessinger, Lori Kunkel, Efrat Dotan, Gregory Otterson, Sai-Hong Ignatius Ou, Tejas Patil, John V. Heymach, Edward S. Kim. CRESTONE – Clinical study of response to seribantumab in tumors with neuregulin-1 (NRG1) Fusions – A phase 2 study of the anti-HER3 mAb for advanced or metastatic solid tumors (NCT04383210) [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PO-003.

Liquid biopsy for lung cancers: an update on recent developments

Liquid biopsy in lung cancer is evolving as an important added tool for screening, early detection, monitoring, and even prognostication of lung cancer. Guidelines and expert recommendations for its use in practice are available and there are specific scenarios in which liquid biopsy is actively being adopted. Several biomarkers, from which important tumor genomic information is obtained, are currently the subject of ongoing investigation. In this review, we summarize the available data on each specific biomarker and provide an overview on how they play a role in current clinical practice.

Abstract 748: Genomic characterization of recurrent small cell lung cancer through research autopsy reveals clonal diversity and candidate driver of chemoresistance

Genomic characterization of recurrent small cell lung cancer (SCLC) is needed to dissect the molecular mechanisms of relapse, metastatic dissemination, and chemoresistance. SCLC is a highly aggressive, lethal neuroendocrine cancer arising from the bronchial epithelium that develops in heavy smokers. Although many SCLC patients demonstrate sensitivity to first-line platinum-doublet chemotherapy, the response is short-lived and nearly all patients progress during therapy or relapse within several months of completing treatment. Treatment options beyond first-line chemotherapy are limited and ineffective. Metastatic SCLC has a poor prognosis and is associated with a 5-year overall survival rate of 5-10%. A well-characterized genetic hallmark of SCLC is the concurrent inactivation of tumor suppressor genes TP53 and RB1. Additional SCLC candidate driver genes have been reported and include CREBBP, MLL, NOTCH1-4, SOX2 and MYC. However, most SCLC tumors profiled in these studies were obtained from treatment-naïve patients. Therefore, genomic alterations that are acquired during therapy and drive the development of chemoresistance in recurrent SCLC remain undefined. We present results from whole exome sequencing (WES) of multiple metastatic tumors procured from five treatment-refractory SCLC patients who underwent research autopsy. WES was also performed on pre-treatment samples from three of these patients. Our results showed universal TP53 alterations and to a lesser extent RB1 mutations in our SCLC cohort. Next, we utilized bioinformatics methods to analyze clonal heterogeneity and evolution in these SCLC patients. This analysis demonstrated the existence of multiple clones of tumor cells in both the pre-treatment and treatment-resistant autopsy SCLC samples, suggesting that tumor heterogeneity occurs early in SCLC development and is subsequently maintained. Furthermore, allele-specific analysis of copy number variations in our SCLC cohort demonstrated near universal deletion of a region on chromosome 5q containing the tumor suppressor APC, consistent with a recently reported role for deregulated WNT signaling in chemoresistance development in relapsed SCLC. Finally, in one SCLC patient, we identified PTEN deletion (loss of heterozygosity) as a potential mechanism of metastasis specifically to the brain. In conclusion, we have performed genomic characterization of recurrent SCLC, defined by significant clonal diversity, through research autopsy and identified candidate genetic drivers of treatment resistance and organ-specific metastasis.

Citation Format: Hui-Zi Chen, Russell Bonneville, Melanie A. Krook, Michele R. Wing, Julie W. Reeser, Jharna Miya, Anoosha Paruchuri, Eric Samorodnitsky, Lianbo Yu, Amy M. Smith, Thuy Dao, Dorrelyn Martin, Qishan Guo, Hailey Magenheim, Aharon G. Freud, Sharon Cole, Gregory Otterson, Peter Shields, David P. Carbone, Patricia Allenby, Sameek Roychowdhury. Genomic characterization of recurrent small cell lung cancer through research autopsy reveals clonal diversity and candidate driver of chemoresistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 748.

Treatment of Lung Cancer Patients With Actionable Mutations in the Intensive Care Unit

BACKGROUND

Patients with advanced-stage non-small-cell lung cancer (NSCLC) have high mortality rates in the intensive care unit (ICU). Although the benefit of chemotherapy for hematologic malignancies in the ICU has previously been explored, few data exist regarding the use of targeted therapy for NSCLC in such settings. The primary objective of the present study was to report our experience with the use of targeted therapy in patients with NSCLC in the ICU.

MATERIALS AND METHODS

We performed a single-institution, retrospective medical record review. The eligibility criteria included patients with NSCLC with targetable mutations who had received tyrosine kinase inhibitors (TKIs) in the ICU. Cases were identified by queries of our institution's information warehouse database and pharmacy dispensary records from 2010 to 2015.

RESULTS

All 9 patients who had received TKIs in the ICU had acute respiratory failure. Three patients were successfully extubated after initiating TKI therapy, although 1 required later tracheostomy. TKI therapy stabilized another patient's refractory disseminated intravascular coagulation. The remaining 5 patients showed no measurable clinical improvement and were transitioned to comfort care. The overall ICU mortality rate was 56%.

CONCLUSION

Patients with metastatic NSCLC requiring mechanical ventilation have high mortality rates. Cytotoxic chemotherapy is generally contraindicated for poor performance status patients. However, targeted TKI therapy should be considered, given its proven efficacy and few systemic side effects. We recommend the empiric use of targeted therapy for NSCLC patients with suspected and/or known actionable mutations presenting with multifactorial respiratory failure to the ICU, with aggressive determination of the mutation status if not known.

Abstract 854: Inhibition of PRMT5 results in radiosensitization in lung cancer cell lines

Background: Protein arginine methylation is a post translational modification that influences signal transduction, mRNA splicing, gene transcription and DNA repair. Among the PRMT family members, PRMT5 is a type II enzyme that symmetrically methylates histone H4 at Arginine 3 and histone H3 at Arginine 8. Studies have recently linked this modification to carcinogenesis and metastasis. The function of PRMT5 in carcinogenesis is related to cell proliferation through modulation of E2F1, p53, EGFR, and CRAF. It is known to accelerate progression through the G1 phase of cell cycle by influencing proteins like CDK4 and CDK6. Previous work on human lung cancer specimens has demonstrated an overexpression of PRMT5 in cancerous tissue when compared to normal lung parenchyma. Suppression of PRMT5 significantly inhibits cell proliferation in lung cancer cell lines A549 and H1299. We hypothesized inhibition of PRMT5 can lead to increased radiosensitivity in lung cancer cells.

Method: Several lung cancer cell lines were used in the experiments, including A549, H1299 and H23. SiRNA (Dharmacon) and lentiviral shRNA (Sigma) were used to knock down (KD) PRMT5 levels transiently or stably in A549 cell line in which p53 is present in its wild type form. Forty eight hours after transient transfection, cells were plated for clonogenic survival assay and subsequently exposed to ionizing radiation at 0, 2, and 8 Gy. Cellular PRMT5 protein levels were estimated by western blotting analysis for PRMT5 KD and scramble control cell lines. The scramble control and siRNA knockdown cells were subjected to cell cycle analysis by flow cytometry. We also tested specific PRMT5 inhibitors with and without radiation therapy in the lung cancer cell lines to see if PRMT5 inhibitors could lead to increased radiosensitivity.

Results: We observed a >90% PRMT5 KD in transiently transfected cells at 48 h and 72 h post transfection as verified by western blot analysis. This transient KD lead to a small but significant decrease in colony survival after radiation. This radiosensitization was not observed in cells selected for stable KD of PRMT5 protein by lentiviral RNA transfection. There is an increase of cell population in G1 arrest in PRMT5 transient KD cells but not in stable KD cells. Additionally, cells treated with PRMT5 specific inhibitors (“cpd5” or “cpd65”) demonstrated increased radiosensitivity in A549 cells but not in H1299 suggesting that this effect may be p53-dependent.

Conclusion: PRMT5 inhibition by siRNA or its specific inhibitors lead to radiosensitivity in A549 lung cancer cell line. This effect may be partially dependent on p53-dependent cell cycle arrest. Further work to inhibit PRMT5 in other lung cancer cell lines with different p53 activities will be investigated.

Citation Format: Smitha Sharma, X Wu, P Smith, N Denko, C Li, H Lai, F Yan, K Shilo, A Chakravarti, S Sif, R Baiocchi, G Otterson, Meng Xu-Welliver. Inhibition of PRMT5 results in radiosensitization in lung cancer cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 854. doi:10.1158/1538-7445.AM2014-854

Detection of extracellular RNAs in cancer and viral infection via tethered cationic lipoplex nanoparticles containing molecular beacons

Noninvasive early detection methods have the potential to reduce mortality rates of both cancer and infectious diseases. Here, we present a novel assay by which tethered cationic lipoplex nanoparticles containing molecular beacons (MBs) can capture cancer cell-derived exosomes or viruses and identify encapsulated RNAs in a single step. A series of ultracentrifugation and Exoquick isolation kit were first used to isolate exosomes from the cell culture medium and human serum, respectively. Cationic lipoplex nanoparticles linked onto the surface of a thin glass plate capture negatively charged viruses or cell-secreted exosomes by electrostatic interactions to form larger nanoscale complexes. Lipoplex/virus or lipoplex/exosome fusion leads to the mixing of viral/exosomal RNAs and MBs within the lipoplexes. After the target RNAs specially bind to the MBs, exosomes enriched in target RNAs are readily identified by the fluorescence signals of MBs. The in situ detection of target extracellular RNAs without diluting the samples leads to high detection sensitivity not achievable by existing methods, e.g., quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Here we demonstrate this concept using lentivirus and serum from lung cancer patients.

Abstract A43: EGFR-targeted therapy in African Americans with advanced non-small cell lung cancer: A prospective clinical, pharmacogenetic, and pharmacokinetic study

Context: Focused evaluation of the efficacy and pharmacokinetics of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), and the potential influence of pharmacogenetics and tumor genetics, has not been previously performed in African American patients with Non-Small Cell lung cancer (NSCLC).

Objective: To evaluate disease control rate (DCR) in African American patients with NSCLC produced by erlotinib, the effect of its titration to rash occurrence, and to characterize pharmacokinetics of parent drug and metabolite, tumor genetics, and pharmacogenetics of erlotinib metabolizing enzymes and transporter genes.

Design, Setting and Patients: 55 African Americans with NSCLC on a 2-stage-minimax randomized phase II study.

Intervention: Patients received erlotinib 150 mg daily or a dose based on body weight with subsequent escalations to 200 mg to achieve skin rash.

Main Outcome Measures: The primary endpoint was DCR (CR+PR+SD) at 3 months. Time to progression and 1-year survival were also evaluated.

Results: 12 of 52 evaluable patients had disease control at 3 months; 6 per arm. Absence of skin rash on therapy was associated with early PD (10/11), exposures for erlotinib and OSI-420 were lower compared to previous reports, and pharmacogenetic factors were consistent with high erlotinib clearance in most patients. Tumor genetics showed one EGFR exon 19 mutation, a novel EGFR exon 20 missense mutation, EGFR amplification in 17/47 samples, 8 KRAS mutations and 5 EML4-ALK translocations.

Conclusions: Results from this trial support the serial linkage of cytochrome P450 pharmacogenetics, erlotinib pharmacokinetics, rash, and response. Factors consistent with high erlotinib metabolism are predominantly present in African Americans. However, the dose-to-rash strategy failed to increase clinical benefit within the dose-range tested, and a relatively high incidence of tumor genetics associated with erlotinib resistance was found. As with other ethnicities, assessment of tumor genetics is recommended. The high clearance data suggests that the concept of standard erlotinib dosing in African American patients should be reconsidered

Citation Format: Mitch Phelps, Thomas Stinchcombe, James S. Blachly, Weiqiang Zhao, Larry J. Schaaf, Sherri L. Starrett, Gregory Otterson, William Hicks, Mark Socinski, Miguel Villalona-Calero. EGFR-targeted therapy in African Americans with advanced non-small cell lung cancer: A prospective clinical, pharmacogenetic, and pharmacokinetic study. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr A43.

Phase I and pharmacokinetic study of mitomycin C and celecoxib as potential modulators of tumor resistance to irinotecan in patients with solid malignancies

PURPOSE

Based on the preclinical evidence of topoisomerase I (Topo-1) upregulation by mitomycin C(MMC) and decreased NF-kappaB activation by celecoxib, we evaluated combinations of irinotecan/MMC and irinotecan/MMC/celecoxib in patients with advanced solid malignancies.

PATIENTS-METHODS

Initially, patients received MMC on day 1 and irinotecan on days 2, 8, 15 and 22, every 6 weeks. MMC dose was fixed at 6 mg/m(2) and cumulative doses of >36 mg/m(2) were not permitted. Irinotecan was escalated in 25 mg/m(2) increments. Due to late-onset diarrhea, the schedule was subsequently shortened to 4 weeks, omitting irinotecan on days 15 and 22. In the second part of the study, celecoxib 400 mg orally twice daily was added to irinotecan/MMC regimen. Potential pharmacokinetic interactions and Topo-1 and DT-diaphorase (NQ01) gene expressions in peripheral-mononuclear cells were evaluated.

RESULTS

Forty-five patients were enrolled. Irinotecan 125 mg/m(2) on days 2 and 8 in combination with MMC 6 mg/m(2) on day 1 every 4 weeks is recommended for future studies; myelosuppression and diarrhea are dose-limiting. The addition of celecoxib resulted in unacceptable toxicities despite reductions on irinotecan's dose. No relevant pharmacokinetic interactions occurred between irinotecan and MMC, and mean increases in Topo-1, were observed. Sixteen of 36 patients evaluable for response-assessment had discernable anti-tumor activity, including 1 complete, 4 partial, 10 minor and 1 tumor marker response. Four patients had prolonged (>4 months) disease-stability (stable disease, not included in CR or PR). Patients experiencing complete and partial responses had higher increments in Topo-1 expression.

CONCLUSIONS

Modulation of irinotecan by MMC is feasible, devoid of pharmacological interactions and active in solid malignancies. The lack of improvement in therapeutic index does not support the addition of celecoxib.

A single center review of the experience with mitomycin C (MMC) and the risk of thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome (HUS)

15167

Background: MMC related TTP/HUS has been reported between 4 and 15%, with a higher incidence in patients receiving cumulative doses of 60 mg or higher. It tends to occur within 4 months of drug administration independently of patients’ cancer status. The ability of MMC to upregulate enzymes relevant for new cytototoxic agents (topoisomerase I for CPT-11 and thymidine phosphorylase for capecitabine) make phamacobiologically based therapeutic combinations including MMC attractive. Methods: All patients (n=100) that participated in four institutional clinical studies from 2000 through 2004 were included. The studies were OSU 9947 (phase I trial of CPT-11 and MMC in solid tumors, n=31) OSU 0151 (phase II trial of CPT-11 and MMC in advanced esophageal and stomach cancer, n=41) OSU 0155 (phase II trial of CPT-11 and MMC in patients with refractory breast cancer, n=26) OSU 0330 (phase I study of capecitabine and MMC in patients with advanced GI tumors n=2). In each study, the maximum cumulative dose of MMC was 36 mg/m2. All patients were followed for clinical signs or symptoms of TTP/HUS including the presence of anemia, thrombocytopenia and renal insufficiency and had a thorough review of the peripheral smear. Results: The median cumulative dose was 12 mg/m2 (range 3–36 mg/m2). No patients met the clinical diagnosis of TTP/HUS except for one patient had anemia, thrombocytopenia and renal insufficiency but did not manifest any other findings consistent with TTP/HUS such as changes in mental status, azotemia or any other clinical symptom. The laboratory abnormalities resolved without intervention within seven days with subsequent continuation on the clinical trial. Conclusions: In this study we have demonstrated that by capping the cumulative dose of MMC to 36 mg/m2, the incidence of TTP/HUS is minimal. Furthermore, our preliminary analysis of an additional 100 patients treated with MMC at OSU shows no reported cases of TTP/HUS (additional data will be presented at the meeting). Since MMC is effective in a wide variety of solid tumors including breast, lung and GI malignancies and is inexpensive and easy to administer, further exploration of MMC in the treatment of solid malignancies is indicated including rational combination studies.

No significant financial relationships to disclose.

Safety and pharmacokinetics (PK) of AMG 706 in combination with panitumumab and gemcitabine-cisplatin in patients (pts) with advanced cancer

14057

Background: AMG 706 is an oral, investigational multikinase (MKI) inhibitor with antiangiogenic and direct antitumor activity that selectively targets VEGF, PDGF and Kit receptors. Methods: This is an ongoing phase 1b, open-label, dose-finding study of AMG 706 plus panitumumab and gemcitabine-cisplatin. Objectives are to establish the maximum tolerated dose and to assess safety, objective response and PK of AMG 706 with this regimen. Pts =18 yrs with advanced cancer, ECOG 0–1, =1 prior chemotherapy for advanced disease and no prior oral VEGFr MKIs or anti EGFR therapy, received panitumumab (9mg/kg IV day 1 of each 3-wk cycle) plus gemcitabine (1250mg/m2 IV days 1 and 8) and cisplatin (75mg/m2 IV day 1), and escalating doses of AMG 706 given continuously from day 1 of cycle 1. Assessments included dose-limiting toxicities (DLT; cycle 1), PK and tumor response (every 6–9 wks from wk 6). Results: As of Nov 2006, 36 pts (NSCLC n=19; pancreatic cancer n=4; other n=10; unknown primary n=3) were enrolled; 42% had prior chemotherapy. There was 1 DLT: pulmonary embolism, grade 5 (50mg QD). Selected treatment-related adverse events in =10% of pts are shown in the table . 39% of pts receiving AMG 706 had thromboembolic events (TE); 25% receiving study therapy without AMG 706 had TEs. There was 1 case of cholecystitis (grade 1), 1 of gallbladder pain (grade 3). Preliminary data showed that AMG 706 PK at 125 mg QD was comparable to data from monotherapy studies at the same dose level. Based on 29 pts with available response data (too early to evaluate/data unavailable n=7), objective tumor responses per RECIST were: CR n=1, 3% (breast cancer); PR n=9, 31% (NSCLC n=6; pancreatic cancer n=2; unknown primary n=1); SD n=17, 59%; PD n=1, 3%. Conclusions: In this study of pts with advanced cancer, AMG 706 was tolerable when combined with panitumumab and gemcitabine-cisplatin, with little effect on AMG 706 PK. Further studies need to determine if the observed TE rate exceeds gemcitabine-cisplatin background rates.

[Table: see text]

No significant financial relationships to disclose.

The role of methylation leading to capecitabine resistant malignant mesothelioma

17105

Background: Malignant mesothelioma is a deadly malignancy whose global incidence continues to be on the rise. Established therapies have been less than optimal. The current therapeutic standard is intravenous pemetrexed, an antifolate medication. Yet, another folate antimetabolite, capecitabine, is significantly less effective than pemetrexed. The enzymes thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), and thymidylate phosphatase (TP) are critical to the efficacy of antifolates. Specifically, for capecitabine to be converted into a potent cytotoxic agent, the enzyme TP must be present and active. In one of four mesothelioma cell lines examined, the gene that encodes for TP, extracellular growth factor-1 (ECGF-1), is methylated. Methylation of this gene and the subsequent downregualtion of the TP enzyme confer a diminished cytotoxic effect by a capecitabine prodrug, dioxyfluridine (DFUR). Methods: Cells were cultured treated with and without 1uM decitabine (DAC) under identical conditions. DNA, RNA, and protein lysates were collected after 72 hours. Bisulfite-treated DNA was examined by MS-PCR for evidence of methylation of TS, DPD, and TP. RNA was collected and cDNA was synthesized. Real time PCR was utilized to detect the relative difference in RNA quantity. Western blots were done to evaluate the differences in protein expression between DAC treated and untreated cells. MTT assay was performed with DAC pretreated and untreated cell lines subsequently treated with DFUR and 5-fluorouracil. Results: One of the four mesothelioma cell lines showed consistent evidence of TP methylation by MS-PCR. The addition of 1uM DAC to the cell lines conferred a six-fold difference in expression of the methylated gene by both real time PCR as well as by Western blot. The prodrug DFUR subsequently shows increased cytotoxicity in the methylated cell line by MTT assay when pretreated with DAC compared when not exposed to the DAC. Conclusion: By demethylating the ECGF-1 gene with DAC, the now upregulated TP enzyme has an increased ability to convert DFUR to 5-FU; thus enhancing the cytotoxicity of a drug thought to be ineffective in malignant mesothelioma.

No significant financial relationships to disclose.

The effectiveness of darbepoetin alfa administered at 300 mcg every 3 weeks on clinical outcomes in elderly patients with chemotherapy-induced anemia

18511

Background: Chemotherapy-induced anemia (CIA) is common in patients (pts) receiving chemotherapy, and reduces health-related quality of life. The primary objective of this exploratory analysis was to describe the effectiveness of darbepoetin alfa administered at 300 mcg every 3 weeks (Q3W) in elderly (≥ 65 years old) and younger pts (< 65 years old) with CIA. Methods: We analyzed data on 1493 pts, enrolled in a multicenter, open-label, 16-week study and who received ≥ 1 dose of darbepoetin alfa. Eligible pts were ≥ 18 years old, had a non-myeloid malignancy, and were anemic (hemoglobin [Hb] < 11 g/dL). Pts were analyzed stratified by age (≥ 65 and < 65 years old) and baseline (BL) Hb (< 10 or ≥ 10 g/dL). Hb-based endpoints were analyzed using 2 approaches: the last value carried forward (LVCF) method, where missing Hb values or values within 28 days of a red blood cell (RBC) transfusion were imputed, or an available data approach, where missing Hb values were not imputed. Pt-reported outcomes were assessed using the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) scale. Results: Pt demographics and disease characteristics varied between the age strata: in the ≥ 65-stratum (mean age = 73.7, n = 724), 52% of pts were women and the most common cancer was gastrointestinal (27%); in the < 65-stratum (mean age = 52.1, n = 769), 69% of pts were women and the most common cancer was breast (41%). Mean (SD) BL FACT-F scores for pts ≥ 65 and < 65 were 27.5 (12.8) vs 27.2 (12.1) for the < 10-g/dL strata and 29.0 (12.5) vs 27.5 (12.0) for the ≥ 10-g/dL strata. Study endpoints are shown in the table. The safety profile was as expected for each age group. Conclusions: Darbepoetin alfa 300 mcg Q3W appears to be as effective in achieving and maintaining Hb between 11 to 13 g/dL in elderly pts as in younger pts with CIA. Since chemotherapy is often administered Q3W, synchronizing darbepoetin alfa treatment with pts’ chemotherapy schedules may simplify the treatment of CIA in this pt population.

[Table: see text]

[Table: see text]

Thalidomide and celecoxib as potential modulators of irinotecan's activity in cancer patients

PURPOSE

Nuclear factor-kappaB (NF-kappaB) activation induces resistance to irinotecan. Preclinically, thalidomide and COX-2 inhibitors reduce NF-kappaB activation. We tested the feasibility of combining irinotecan with thalidomide and thalidomide/celecoxib in patients with refractory malignancies.

PATIENTS/METHODS

The study was conducted in two parts. First, the optimal dose of thalidomide (400 or 200 mg daily) in combination with irinotecan 125 mg/m(2) days 1 and 8 every 3 weeks was determined. In the second part, celecoxib 400 mg twice-daily was added to irinotecan/thalidomide. Pharmacokinetics of irinotecan and thalidomide alone or concurrently were evaluated. Tumor necrosis factor alpha, beta-fibroblast growth factor, and NF-kappaB activation were measured in blood mononuclear cells (PBMC). No CYP450 enzyme inducers/inhibitors were allowed.

RESULTS

Thirty-six patients were enrolled: Eleven received thalidomide 400 mg, 13 thalidomide 200 mg and 12 thalidomide 400 mg and celecoxib, with irinotecan. For the two-drug combination, there was a higher rate of moderate/severe diarrhea/myelosuppression with thalidomide 200 mg. Thus thalidomide 400 mg was combined with celecoxib. The triple combination resulted in similar toxicity as the doublet with the lower thalidomide dose. Concurrent administration of irinotecan/thalidomide did not influence pharmacokinetics. Anti-tumor responses occurred in two patients and prolonged stabilization in eight others. NF-kappaB activation increased over time. Patients experiencing tumor response or prolonged stabilization had lower NF-kappaB activation, albeit not statistically significant (P = 0.124).

CONCLUSIONS

The combination of thalidomide/irinotecan is safe and devoid of PK interactions. Thalidomide 400 mg appeared more suitable for combination, whereas the addition of celecoxib did not improve tolerability. Tumor-specific studies in patients with lesser prior treatment will be necessary to establish the therapeutic impact of the combinations.

Incorporation of photodynamic therapy as an induction modality in non-small cell lung cancer

BACKGROUND AND OBJECTIVES

Incorporation of photodynamic therapy (PDT) into the induction therapy regimen utilized for treatment of locally advanced primary non-small cell bronchogenic carcinoma (NSCLC) is explored.

STUDY DESIGN/MATERIALS AND METHODS

We present a retrospective review of 41 patients diagnosed with non-metastatic NSCLC who underwent induction PDT with chemotherapy and/or radiation.

RESULTS

Fifty percent of patients initially deemed unresectable, were able to undergo definitive surgical resection after trimodality induction therapy. Twenty-seven percent of patients considered to require pneumonectomy were able to have a lobectomy. The pathological stage was less than the preinduction clinical stage in 14 of 22 cases; of which four patients had no residual tumor. There was no 30/90-day postoperative mortality. Mean survival was 35.9 months (lobectomy), 25.5 months (pneumonectomy) and 14.7 months (no surgery). Median survival was 78% (12 months) and 46% (36 months). The main postoperative complication following pneumonectomy was bronchopleural fistula formation. All patients who developed this complication had undergone trimodality induction therapy. Incorporation of PDT into the induction arsenal for patients with loco-regionally advanced NSCLC may be safely performed.

CONCLUSIONS

PDT may define an alternative induction strategy for patients requiring pneumonectomy; further studies exploring the true efficacy of PDT as an induction modality are encouraged.