Phase 1b study of combined selinexor and eribulin for the treatment of advanced solid tumors and triple-negative breast cancer

BACKGROUND

Selinexor (KPT-330) is a potent inhibitor of exportin 1 (XPO1), in turn inhibiting tumor growth. Selinexor enhances the antitumor efficacy of eribulin in triple-negative breast cancer (TNBC) in vitro and in vivo. Given the unmet medical need in TNBC and sarcoma, the authors explored the safety and efficacy of this combination.

METHODS

The authors conducted a phase 1b trial of combined selinexor and eribulin using a 3 + 3 dose-escalation design in patients who had advanced solid tumors and in those who had TNBC in a dose-expansion cohort.

RESULTS

Patients with TNBC (N = 19), sarcoma (N = 9), and other cancers (N = 3) were enrolled in the dose-escalation cohort (N = 10) and in the dose-expansion cohort (N = 21). The median number lines of prior therapy received was four (range, from one to seven prior lines). The most common treatment-related adverse events for selinexor were nausea (77%), leukopenia (77%), anemia (68%), neutropenia (68%), and fatigue (48%). One dose-limiting toxicity occurred at the first dose level with prolonged grade 3 neutropenia. The recommended phase 2 dose was 80 mg of selinexor orally once per week and 1 mg/m² eribulin on days 1 and 8 intravenously every 3 weeks. The objective response rate (ORR) was 10% in three patients. In the dose-escalation cohort, the ORR was 10%, whereas six patients with had stable disease. In the TNBC dose-expansion cohort (n = 18), ORR was 11%, and there were two confirmed partial responses with durations of 10.8 and 19.1 months (ongoing).

CONCLUSIONS

Selinexor and eribulin had an acceptable toxicity profile and modest overall efficacy with durable responses in select patients.

PLAIN LANGUAGE SUMMARY

Effective therapies for advanced, triple-negative breast cancer and sarcoma represent an unmet need. Exportin 1 is associated with the transport of cancer-related proteins. Preclinical studies have demonstrated tumor growth inhibition and enhanced tumor sensitivity in patients who receive selinexor combined with eribulin. In this phase 1b study, the authors evaluated the safety profile and clinical activity of the combination of selinexor, a potent oral inhibitor of exportin 1, and eribulin in patients with advanced cancers enriched for triple-negative breast cancer or sarcoma. The combination was well tolerated; most adverse events were mild or moderate, reversible, and managed with dose modifications or growth factor support. The combination of selinexor and eribulin produced an antitumor response, particularly in some patients with triple-negative breast cancer. This work lays the foundation for prospective investigations of the role of selinexor and eribulin in the treatment of triple-negative breast cancer.

BRAF v600E-mutant cancers treated with vemurafenib alone or in combination with everolimus, sorafenib, or crizotinib or with paclitaxel and carboplatin (VEM-PLUS) study

Combined BRAF + MEK inhibition is FDA approved for BRAF V600E-mutant solid tumors except for colorectal cancer. However, beyond MAPK mediated resistance several other mechanisms of resistance such as activation of CRAF, ARAF, MET, P13K/AKT/mTOR pathway exist among other complex pathways. In the VEM-PLUS study, we performed a pooled analysis of four phase one studies evaluating the safety and efficacy of vemurafenib monotherapy and vemurafenib combined with targeted therapies (sorafenib, crizotinib, or everolimus) or carboplatin plus paclitaxel in advanced solid tumors harboring BRAF V600 mutations. When vemurafenib monotherapy was compared with the combination regimens, no significant differences in OS or PFS durations were noted, except for inferior OS in the vemurafenib and paclitaxel and carboplatin trial (P = 0.011; HR, 2.4; 95% CI, 1.22-4.7) and in crossover patients (P = 0.0025; HR, 2.089; 95% CI, 1.2-3.4). Patients naïve to prior BRAF inhibitors had statistically significantly improved OS at 12.6 months compared to 10.4 months in the BRAF therapy refractory group (P = 0.024; HR, 1.69; 95% CI 1.07-2.68). The median PFS was statistically significant between both groups, with 7 months in the BRAF therapy naïve group compared to 4.7 months in the BRAF therapy refractory group (P = 0.016; HR, 1.80; 95% CI 1.11-2.91). The confirmed ORR in the vemurafenib monotherapy trial (28%) was higher than that in the combination trials. Our findings suggest that, compared with vemurafenib monotherapy, combinations of vemurafenib with cytotoxic chemotherapy or with RAF- or mTOR-targeting agents do not significantly extend the OS or PFS of patients who have solid tumors with BRAF V600E mutations. Gaining a better understanding of the molecular mechanisms of BRAF inhibitor resistance, balancing toxicity and efficacy with novel trial designs are warranted.

Examining Stripes on a Herd of Zebras: Impact of Genomic Matching for Ultrarare Sarcomas in Phase 1 Clinical Trials (SAMBA 102)

PURPOSE

Recently, the Connective Tissue Oncology Society published consensus guidelines for recognizing ultrarare sarcomas (URS), defined as sarcomas with an incidence ≤1 per 1,000,000. We assessed the outcomes of 56 patients with soft tissue, and 21 with bone sarcomas, enrolled in Phase 1 trials.

EXPERIMENTAL DESIGN

In this Sarcoma-Matched Biomarker Analysis (SAMBA-102 study), we reviewed records from patients on Phase 1 trials at the University of Texas MD Anderson Cancer Center between January 2013 and June 2021.

RESULTS

Among 587 sarcomas, 106 (18.1%) were classified as URS. Fifty (47%) were male, and the median age was 44.3 years (range, 19-82). The most common subtypes were alveolar soft part sarcoma (ASPS), chordoma, dedifferentiated chondrosarcoma, and sclerosing epithelioid fibrosarcoma. Compared with common sarcomas, median OS was similar 16.1 months [95% confidence interval (CI), 13.6-17.5] versus 16.1 (95% CI, 8.2-24.0) in URS (P = 0.359). Objective response to treatment was higher in URS 13.2% (n = 14/106) compared with common sarcomas 6.9% (n = 33/481; P = 0.029). Median OS for those treated on matched trials was 27.3 months (95% CI, 1.9-52.7) compared with 13.4 months (95% CI, 6.3-20.6) for those not treated on matched trials (P = 0.291). Eight of 33 (24%) molecularly matched treatments resulted in an objective response, whereas 6 of 73 unmatched treatments (8.2%) resulted in an objective response (P = 0.024). Clinical benefit rate was 36.4% (12/33) in matched trials versus 26.0% (19/73) in unmatched trials (P = 0.279).

CONCLUSIONS

The results demonstrate the benefit of genomic selection in Phase 1 trials to help identify molecular subsets likely to benefit from targeted therapy.

Selinexor in combination with weekly paclitaxel in patients with metastatic solid tumors: Results of an open label, single-center, multi-arm phase 1b study with expansion phase in ovarian cancer

OBJECTIVE

Selinexor is a first-in-class, oral selective inhibitor of nuclear export (SINE) compound which blocks Exportin-1 (XPO1). Our objective was to determine maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of selinexor and weekly paclitaxel.

METHODS

This was an open label, single-center, multi-arm phase 1b study utilizing a "3 + 3" design and a "basket-type" expansion in recurrent solid tumors. Selinexor (60 mg or 80 mg twice weekly orally) and weekly paclitaxel (80 mg IV 2 week on, 1 week off) were one of 13 parallel arms. Efficacy was evaluated using RECIST version 1.1.

RESULTS

All 35 patients treated were evaluable for toxicity and 31 (88%) were evaluable for response. Patient diagnoses included platinum-resistant/refractory ovarian (n = 28), breast (n = 4), prostate (n = 2), and cervical (n = 1) cancer. Patients had a median of four prior therapies (range 1-10), and 47% had a prior taxane in the recurrent setting. There were no DLTs and 60 mg was chosen as the RP2D due to long-term tolerability. Ninety-seven percent of patients had at least one treatment-emergent adverse event (TEAE), and the most common grade ≥ 3 TEAE were neutropenia (46%), anemia (31%), and nausea (21%). Among 24 evaluable patients with ovarian cancer, response rate was 17%, CBR was 58%, and median PFS was 6.8 months (95% CI 3.7, not reached (NR)).

CONCLUSIONS

Oral selinexor in combination with weekly paclitaxel demonstrated promising clinical activity with manageable toxicity. This combination should be considered for further exploration in a randomized study, especially in ovarian malignancies.

Abstract 5237: B-Raf V600E harboring non-melanoma cancers treated with Vemurafenib monotherapy and in combination with Everolimus/Sorafenib/Crizotinib/Paclitaxel+ Carboplatin: A pooled analysis of five phase 1/2 studies

BACKGROUND: BRAF V600 mutations are driver oncogenes in multiple human cancers. Given complex resistance mechanisms beyond combined MEK inhibition, limited data exists to evaluate combinations with CRAF/ARAF/MET/mTOR inhibitors and cytotoxic chemotherapy in sustaining response and overcoming resistance. We explore patient outcomes comparing vemurafenib monotherapy with the above combination therapies in this analysis.

METHODS: A pooled analysis of 5 phase 1/2 clinical trials containing vemurafenib was conducted between January 2012 and October 2020 in BRAF V600E mutant advanced or metastatic tumors. Overall survival (OS) and Progression free survival (PFS) in vemurafenib monotherapy (V) arm compared with vemurafenib + crizotinib (VC), vemurafenib + sorafenib (VS), vemurafenib + everolimus (VE) and vemurafenib + paclitaxel + carboplatin (VPC) arms were assessed. Objective Response Rate (ORR) and Clinical Benefit Rate (CBR=CR+PR+SD≥6 months) and safety profile of combination arms were also explored.

RESULTS: 99 patients were enrolled across 5 studies. Median age was 57 years with 78% of ECOG 1 and M:F ratio at 1:1. Tumor types included NSCLC (13%), Thyroid cancer (12%), Low and High-grade Gliomas (7%), Colorectal cancer (6%), Cholangiocarcinoma (5%) and ECD (3%). V arm derived greatest clinical benefit with median OS at 21 months while addition of PC arm dropped median OS to 2 months. Inferior OS was seen in VPC arm when compared to V arm (p=0.00616). Median PFS peaked at 11 months in VC arm versus 3 months for the VPC arm. Of 85 evaluable patients, 2 complete responses were noted in the V (n=25) and VPC (n=14) arms and 8 Partial Responses (PR) were noted with 5 (18%) patients with NSCLC in V arm followed by 4 PRs in the VC (n=12) arm. PR rates were equally seen in the other arms. ORR (36%) and CBR (40%) rates were the highest for the V arm. G3/G4 treatment related adverse events with neutropenia (63%), thrombocytopenia (50%) and fatigue (63%) were highest in VPC. 1 patient died from G4 thrombocytopenia with intracranial hemorrhage in the VPC arm.

CONCLUSIONS: No significant added clinical benefit was noted when vemurafenib was combined with other targeted agents or cytotoxic therapy. Combinations resulted in poor tolerance and need for dose reductions compromising clinical efficacy. Prospective studies to analyze resistance mechanisms to BRAF inhibitor therapy in BRAF+ tumors and in real time tailoring therapy based on co-occuring alterations is warranted.

Citation Format: Blessie Elizabeth Nelson, Jason Roszik, Filip Janku, David Hong, Shumei Kato, Aung Naing, Sarina Piha-Paul, Siqing Fu, Apostolia Tsimberidou, Maria Cabanillas, Naifa Busaidy, Milind Javle, Lauren Byers, John Heymach, Funda Meric-Bernstam, Vivek Subbiah. B-Raf V600E harboring non-melanoma cancers treated with Vemurafenib monotherapy and in combination with Everolimus/Sorafenib/Crizotinib/Paclitaxel+ Carboplatin: A pooled analysis of five phase 1/2 studies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5237.

Spectrum of Immune Checkpoint Inhibitor Anemias: Results From a Single Center, Early-Phase Clinical Trials Case Series Experience

Immune checkpoint inhibitor anemias (ICI-A) are a rare entity which can be potentially life-threatening without prompt identification. The goal of the study is to characterize the presentation, evaluation, and outcomes of ICI therapy in early phase clinical trial setting to guide future research and to develop standardized care guidelines. Retrospective chart review of 333 patients who participated in early phase clinical trials at the University of Texas MD Anderson Cancer Center revealed four cases with ICI-A between 2016 and 2020. We identified a spectrum of four cases which included ICI-related autoimmune hemolytic anemias, hemophagocytic lymphohistiocytosis and thrombotic microangiopathy as a result of combinatory investigational therapies involving ICI. Patient presentation, evaluation, bone marrow pathology, interventions, and clinical course were reviewed. The median time to onset of hematological immune-related adverse events (heme-irAEs) in this retrospective series was 3.5 weeks (2 - 6 weeks). One patient had pre-existing untreated chronic lymphocytic leukemia. Glucocorticoids are an effective first-line treatment in most patients although most patients were not rechallenged but successfully had complete recovery and pursued further non-immunotherapy-based therapies. Cognizance of ICI-A in clinical trial setting is paramount to early recognition of heme-irAEs. Further research is needed to identify and stratify risk factors during clinical trial enrollment and optimal management strategies for immune-mediated hematologic toxicities.

500 SYNB1891, a bacterium engineered to produce a STING agonist, demonstrates target engagement in humans following intratumoral injection

Background

SYNB1891 is a live, modified strain of probiotic E. coli Nissle engineered to produce cyclic dinucleotides under hypoxia leading to stimulator of interferon genes (STING)-activation in phagocytic antigen-presenting cells in tumors and activating complementary innate immune pathways.

Methods

This first-in-human study (NCT04167137) enrolled patients with refractory advanced solid tumors to receive intratumoral (IT) injections of SYNB1891 monotherapy or in combination atezolizumab. Patients enrolled in the monotherapy arms received doses of 1x106 - 3x108 live cells on Days 1, 8 and 15 of the first 21-day cycle and then on Day 1 of each subsequent cycle. Patients enrolled in the 2 combination cohorts received doses of 1x107 - 3x107 live cells in combination with atezolizumab administered on a 21-day cycle. The primary objective of the study was to evaluate safety and tolerability of SYNB1891 alone and in combination with atezolizumab. Other objectives include SYNB1891 kinetics in blood and injected tumor, STING-target engagement as assessed by IT gene expression and serum cytokines, and tumor responses.

Results

This interim analysis includes 23 patients across 6 monotherapy cohorts dosed at 1x106, 3x106, 1x107, or 3x107, 1x108 and 3x108 live cells, and 7 patients dosed in 2 combination therapy cohorts (1x107 and 3x107 live cells). The mean (range) age was 61 (25–82); 19 patients were female. There were 4 cytokine release syndrome events in monotherapy cohorts, including one grade 3 event which met the criterion for dose limiting toxicity at 3x108 live cells; there were no other SYNB1891-related serious adverse events. There were no SYNB1891-related infections. SYNB1891 was not detected in the blood at 6 or 24 hours after the first dose or intratumorally 7 days following the first dose. Treatment with SYNB1891 demonstrated activation of the STING pathway and target engagement as assessed by upregulation of interferon-stimulated genes (ISG15, IFIT1, IFIt2), chemokines/cytokines (CXCL9, CXCL10, TNFRS18, TNFSF10) and T-cell response genes (GZMA, CD4, PD-L2) in core biopsies obtained pre-dose and 7 days following the third weekly dose. In addition, there was a dose-response increase in serum cytokines. Durable, stable disease was observed in two patients treated with SYNB1891 monotherapy refractory to prior PD-1/L1 antibodies with vulvar melanoma (1x106 live cells; RECIST -28%) and small cell lung cancer (1x107 live cells; RECIST -12%).

Conclusions

Repeat IT injection of SYNB1891 as monotherapy and in combination atezolizumab in this ongoing study is safe and well-tolerated up to at least 1x108 live cells, and shows evidence of STING pathway target engagement.

Acknowledgements

We thank Inessa Vulfova for her clinical support in conduct of this study.

Trial Registration clinicaltrials.gov (NCT04167137)

Ethics Approval

The study protocol, the informed consent form (ICF), and printed subject information materials were reviewed and approved by the institutional review board (IRB) at the investigational site before any study procedures were performed. Written informed consent to participate in the study was obtained from each subject before any study-specific procedures were performed.The Ohio State University Cancer Institutional Review Board; Approval ID: 2020C0194MD Anderson Cancer Center Institutional Review Board; Approval ID: 2019–0576Mary Crawley Medical Research Center Institutional Review Board; Approval ID: 19–31 SYNB1891-CP-001North Texas Institutional Review Board; Approval ID: 2019.040WIRB Approval ID: 20192779University of Pittsburgh Institutional Review Board Approval ID: STUDY20010116

529 Phase 1 study of INCB086550, an oral PD-L1 inhibitor, in immune-checkpoint naive patients with advanced solid tumors

Background

INCB086550 is an orally administered small molecule that binds PD-L1 and inhibits PD-1/PD-L1 interaction. Translational data demonstrating markers of immune activation in patients following INCB086550 were previously reported.1 Preliminary clinical data from this phase 1 study are presented below.

Methods

Adult patients (≥18 years) with advanced solid tumors were enrolled into this open-label study. Patients had disease progression after standard available therapy or were intolerant of or ineligible for standard treatment. Measurable disease was required. A modified 3+3 dose-escalation design was employed, followed by dose expansions. The primary endpoints were safety and tolerability of INCB086550, identification of a pharmacologically active dose and/or MTD, and confirmation of the RP2D. Secondary endpoints included PK, pharmacodynamics, and efficacy as assessed by investigator-determined ORR and DCR (CR, PR, or SD ≥12 weeks).

Results

As of 9Apr2021, 79 patients received treatment (Table 1); 57.0% were female, 62.0% had ≥2 prior lines of therapy, and 16% received prior IO treatment. Forty-six (58.2%) patients had treatment-related TEAEs; those occurring in ≥5% of patients are presented in Table 2. Ten patients (12.7%) had grade ≥3 treatment-related TEAEs. Immune-related TEAEs occurred in 15 patients (19.0%); the most common (>1 patient) included peripheral sensory neuropathy (n=5), pruritus (n=3), immune-mediated neuropathy (n=2), and peripheral motor neuropathy (n=2). In total, 10 (12.7%) patients had TEAEs of peripheral neuropathy; all were grade ≤3. All grade 2 or 3 TEAEs of peripheral neuropathy resolved or improved with either study drug continuation without dose modification, dose reduction, or drug interruption/discontinuation. Patients with TEAEs leading to treatment interruption were 21 (26.6%), dose reduction 5 (6.3%), and discontinuation 13 (16.5%). Five patients (6.3%) died of a TEAE (cerebrovascular accident, dyspnea, general physical health deterioration, intestinal obstruction, intracranial hemorrhage [each n=1]); all fatal TEAEs were considered unrelated to study drug. The efficacy-evaluable population included 68 patients; ORR was 11.8% (95%CI, 5.2%–21.9%; CR, 1.5%; PR, 10.3%), and DCR was 19.1% (95%CI, 10.6%–30.5%; Table 3). Eight objective responses were observed at doses ≥400 mg BID (Table 4); 3 of these were noted among the 5 IO treatment-naive patients with MSI-H tumors who received 400 mg BID.

Conclusions

Immune-related AEs observed in this ongoing phase 1 study are consistent with those seen with antibody immune checkpoint inhibitors, with the exception of peripheral neuropathy. Preliminary efficacy of INCB086550 in tumor types known to be responsive to anti-PD-(L)1 therapy is encouraging and warrants further investigation.

Trial Registration

Clinicaltrials.

gov identifier NCT03762447

References

Piha-Paul S, et al. J Immunother Cancer. 2020;8(suppl 3):A255.

Ethics Approval

The study protocol was approved by institutional review boards (IRB) or independent ethics committees at participating centers. All study participants gave informed consent before taking part. The approval numbers were: Integ Review IRB (Austin, TX), RM 598; MD Anderson Cancer Center Office of Human Subject Protection (Houston, TX), IRB ID 2018-0765; ADVARRA (Columbia, MD), IRB# 00000971; Ethisch Comité/Comité d’ Ethique Hospital (Brussels, Belgium), A2021/085; Hôpital Saint-Louis (Paris, France), Prof Le Tourneau – 2020-118/Ref. of the Promoter 0.09.22.72214; NHS Health Research Authority London - City & East Research Ethics Committee (Bristol, UK), IRAS project ID:282291/REC reference: 20/LO/1001; Comitato Etico IRCCS Pascale (Milan, Italy), ISS Validation Protocol Number 29111(2020)-PRE21-1835; Comitato Etico Della Fondazione IRCCS ”Istituto Nazionale Dei Tumori”- Milano CE150053 (Milan, Italy), INT 230/20; Comitato Etico Regione Toscana - Area Vasta Sud Est CE150047, 18064; Comitato Etico Indipendente Istituto Clinico Humanitas CE150081, 940/20; Regulatory Pharma Net (Pisa, Italy), IEC 1393.

Abstract 529 Table 1

Number of patients per dose level

BID, twice daily; QD, once daily.

The tumor types in the study included breast, cervical, colorectal, endometrial, esophageal, gastric, hepatocellular, melanoma, mesothelioma, ovarian, small cell lung cancer, squamous cell carcinoma of the head and neck, renal cell, urothelial, adrenal, anal, cholangiocarcinoma, gall bladder, pancreatic, penile, salivary gland, sarcoma, vaginal, prostate, basal cell, pleomorphic sarcoma, fallopian, carcinoma of parotid gland, well-differentiated liposarcoma, myoepithelial, castrate-resistant prostate cancer, cancer of unknown primary, neuroendocrine, prostate adenocarcinoma with neuroendocrine differentiation, glioblastoma, anal canal, angiosarcoma, and gastroesophageal junction.

Abstract 529 Table 2

Treatment-related TEAEs reported by ≥5% of patients (N=79)

TEAE, treatment-emergent adverse event.

Abstract 529 Table 3

Summary of best overall response by RECIST v1.1 or RANO*

CR, complete response; DCR, disease control rate; GBM, glioblastoma; ORR, objective response rate; PR, partial response; RANO, Response Assessment of Neuro-Oncology; RECIST, Response Evaluation Criteria in Solid Tumors; SD, stable disease.

* 1 patient with GBM was assessed by RANO and had best overall response of progressive disease.

† The efficacy-evaluable population included all solid tumor participants enrolled in the study who received at least 1 dose of INCB086550, completed a baseline scan, and met at least 1 of the following criteria: ≥1 postbaseline scan, participant had been on the study for a minimum of 63 days of follow-up, or participant had discontinued from treatment.

‡ ”Not evaluable” indicates participants in the efficacy-evaluable population that did not have valid postbaseline overall response assessments by RECIST or RANO.

§ ”Not assessed” indicates participants in the efficacy-evaluable population that did not have any postbaseline overall response assessments by RECIST or RANO.

Abstract 529 Table 4

Tumor types with investigator-assessed objective response per RECIST v1.1 (n=8)

BID, twice daily; dMMR, deficient mismatch repair; IO, immuno-oncology; MSI-H, high microsatellite instability; RECIST, Response Evaluation Criteria in Solid Tumors.

+Ongoing response.

Validation of Prognostic Scores in Patients With Metastatic Urothelial Cancer Enrolling in Phase I Targeted Therapy or Next Generation Immunotherapy Trials

INTRODUCTION

Enrolling patients with metastatic urothelial carcinoma (mUC) in phase I trials provides an opportunity to identify biological drug activity. Developing prognostic scores may aid in patient selection for phase 1 trials.

PATIENTS AND METHODS

We analyzed records of patients with mUC who participated in targeted therapy and immunotherapy phase I clinical trials at MD Anderson Cancer Center (MDACC). The Bellmunt and Bajorin scores were calculated as bladder cancer-specific prognostic scores. The Royal Marsden Hospital (RMH) and MDACC scores were calculated as phase I prognostic scores. Hazard ratios (HR) were calculated using the Cox proportional hazard model. The prognostic value of the Bellmunt, Bajorin, RMH, and MDACC scores were assessed using the Likelihood ratio (LR) χ2 test and the c-index.

RESULTS

Between 2015 and 2019, 43 patients were enrolled in phase I trials and 12 were enrolled in >I trial leading to a total of 57 trial participants (TPs). Ninty-seven percent of TPs received prior platinum therapy and 60% received a prior checkpoint inhibitor. Median overall survival (OS) and progression-free survival (PFS) were significantly shorter with increasing Bajorin, RMH, or MDACC scores, but not with increasing Bellmunt score. The RMH (c-index=0.658, LR χ2=11.8, P=.008) and MDACC scores (c-index =0.66, LR χ2=12.76, P=.01) outperformed the Bajorin score (c-index=0.522, LR χ2=1.22, P=.5) and the Bellmunt score (c-index=0.537, LR χ2=0.36, P=.9) in predicting overall survivalover. The Bajorin, RMH, and MDACC scores, but not the Bellmunt score, were also predictive of progression-free survival (PFS)prog. The RMH and MDACC scores again outperformed the Bajorin scoreand the Bellmunt score for predicting PFS.

CONCLUSION

The RMH and MDACC phase I prognostic scores accurately predicted survival in patients with mUC and outperformed the bladder cancer-specific scores at time of enrollment on phase 1 clinical trials. The RMH and MDACC scores could optimize selection of patients with mUC for phase I clinical trials.

Abstract CT115: Phase I trial of the triplet berzosertib (M6620, VX-970), veliparib and cisplatin (BVP) in patients with advanced solid tumors

Background: Ataxia-telangiectasia-related (ATR) protein kinase is central to the repair of damaged DNA through the homologous recombination (HR) pathway. We conducted a phase I trial of cisplatin in combination with the ataxia-telangiectasia-related (ATR) protein kinase inhibitor berzosertib (M6620) and the poly (ADP-ribose) polymerase (PARP) 1/2 inhibitor veliparib, postulating that simultaneous PARP and ATR inhibition impairs DNA repair and induces a “BRCA null”-like phenotype which could potentiate the antitumor activity of cisplatin. We evaluated the safety, maximal tolerated dose (MTD) and preliminary anti-tumor activity of this treatment triplet. The study was conducted through the Experimental Therapeutics Clinical Trials Network (ETCTN). Methods: This open label trial used a 3+3 design. Cisplatin and berzosertib were each administered intravenously on separate, sequential days for two continuous weeks [day (D) 1 and 8; D2 and 9 respectively], together with veliparib orally twice daily during IV therapy and for 24 hours after (D1-3 and 8-10) in 21-day cycles. Prior platinum and PARP inhibitor therapy were permitted. Tumor expression of DNA damage repair (DDR) biomarkers was assessed at the MTD using validated, quantitative immunofluorescence assays. Results: Fifty-three patients (pts) enrolled, 46 pts evaluable for response. The MTD and RP2D dose is cisplatin 40 mg/m2 D1 and D8, berzosertib 210 mg/m2 D2 and D9, and veliparib 200mg BID (D1-3, D8-10). Three patients achieved a confirmed partial response (PR; 5.6%). A further 2 patients had an unconfirmed PR (breast carcinoma, -30%; HGS carcinoma, -36%). Four responders (3 PR and 1 uPR) received prior platinum. Median time on study: 4 cycles (range 1-25). Genomic data was available on four pts achieving a response: ovarian cancer (BRCA-wildtype, ATM unknown; 25 cycles), breast carcinoma (ATM mutation; 14 cycles), SCC of the tongue (Chek2 mutation; 20 cycles), and HGS carcinoma (ATM/BRIP1 mutation; 4 cycles). Twenty-six pts (56.5%) had stable disease. Thirty-five patients (66.0%) required dose reduction in at least 1 agent, most commonly veliparib (25; 47.2%). Most common grade 3 and 4 adverse events were related to myelosuppression: anemia (20; 37.7%), thrombocytopenia (17; 32.1%), leukopenia (13; 24.5%), neutropenia (12; 22.6%), and lymphopenia (11; 20.8%). Ongoing pharmacodynamic analyses of tumor biopsies collected on C1D1 (post-veliparib/cisplatin) and C1D9 (post-veliparib/cisplatin/M6620) have demonstrated a combination-induced increase in RAD51, indicative of replication stress. Conclusions: The BVP combination shows anti-tumor activity in HR-compromised tumors and M6620 further increases the DDR response elicited by combination cisplatin/veliparib.

Citation Format: Geraldine O'Sullivan Coyne, Khanh T. Do, Shivaani Kummar, Naoko Takebe, Sarina Piha-Paul, Richard Piekarz, Deborah Wilsker, Brandon Miller, Katherine Ferry-Galow, Ralph Parchment, Lamin Juwara DNP, Mary Jane Ong, Arjun Mittra, James H. Doroshow, Alice P. Chen. Phase I trial of the triplet berzosertib (M6620, VX-970), veliparib and cisplatin (BVP) in patients with advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT115.

Abstract LB057: Whole exome sequencing of tumor tissue and circulating tumor DNA ingastrointestinal stromal tumors (GIST)

Background: The discovery of oncogenic mutations as potential targets for cancer therapy has revolutionized the treatment of GIST and other cancers. However, adaptive resistance ultimately develops in nearly all patients, which emphasizes the need for a more detailed understanding of the underlying molecular profile. Methods: Using the Personalis ImmunoID NeXT Platform® (Personalis, Inc.; Menlo Park, CA), an augmented exome/transcriptome platform and analysis pipeline, we performed whole exome sequencing (WES) and whole transcriptome total RNA sequencing (RNA-Seq) of paired baseline tumor and normal tissue. NeXT Liquid Biopsy™ (Personalis, Inc.) was used for WES of plasma-derived ctDNA from serially collected samples collected at baseline, after 1 month and at progression to experimental systemic therapies in 15 patients with advanced/metastatic GIST. Results: WES of tumor tissue samples from all 15 patients confirmed underlying KIT mutation in all patients. There was large heterogeneity of other molecular alterations, which included therapeutically relevant molecular alterations, such as microsatellite instability-high (MSI-high) in 1 sample. RNA-Seq of tumor tissue revealed recurrent overexpression of GALR2, NY-ESO-1 and other genes involved in cancer progression, angiogenesis and anticancer immunity. Patients with response to systemic therapies demonstrated lower levels of cytolytic activity measured by CYT score in tumor tissue compared to patients without response (P=0.04). KIT mutations were detected in serially collected ctDNA samples from 12 (80%) of 15 patients. Quantity of KIT and other mutant ctDNA dynamically tracked the clonal evolution and clinical course during systemic therapy. Conclusions: Comprehensive genomic profiling (WES and RNA-Seq) of tumor tissue and WES of serially collected ctDNA is feasible and detects underlying druggable KIT mutations and other molecular alterations.

Citation Format: Niamh Coleman, Charles Abbot, Neeta Somaiah, Sarina Piha-Paul, Shubham Pant, Jordi Rodon, S. Greg Call, Sean Boyle, Funda Meric-Bernstam, Filip Janku. Whole exome sequencing of tumor tissue and circulating tumor DNA ingastrointestinal stromal tumors (GIST) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB057.

Patient-Reported Out-of-Pocket Costs and Financial Toxicity During Early-Phase Oncology Clinical Trials

BACKGROUND

Clinical trials are an important therapeutic option for patients with cancer. Although financial burden in cancer treatment is well documented, the financial burden associated with clinical trials is not well understood.

PATIENTS AND METHODS

We conducted a survey regarding economic burden and financial toxicity in patients with cancer enrolled in phase I clinical trials for >1 month. Financial toxicity score was assessed using the Comprehensive Score for Financial Toxicity survey. Patients also reported monthly out-of-pocket (OOP) costs.

RESULTS

Two hundred and thirteen patients completed the survey (72% non-Hispanic White; 45% with annual income ≤$60,000; 50% lived >300 miles from the clinic; 37% required air travel). Forty-eight percent of patients had monthly OOP costs of at least $1,000. Fifty-five percent and 64% of patients reported unanticipated medical and nonmedical expenses, respectively. Worse financial toxicity was associated with yearly household income <$60,000 (odds ratio [OR]: 2.7; p = .008), having unanticipated medical costs (OR: 3.2; p = .024), and living >100 miles away from the clinical trial hospital (OR: 2.3; p = .043). Non-White or Hispanic patients (OR: 2.5; p = .011) and patients who were unemployed or not working outside the home (OR: 2.5; p = .016) were more likely to report high unanticipated medical costs.

CONCLUSION

Among patients with cancer participating in clinical trials, economic burden is high, and most of patients' OOP costs were nonmedical costs. Financial toxicity is disproportionally higher in patients with lower income and those who travel farther, and unexpected medical costs were more common among non-White or Hispanic patients. OOP costs can be substantial and are often unexpected for patients.

IMPLICATIONS FOR PRACTICE

The financial burden of cancer treatment is well documented, but there are limited data regarding the financial burden associated with cancer clinical trials. This study surveyed 213 patients enrolled in early-phase clinical trials. Monthly out-of-pocket costs were at least $1000 for nearly half of patients. Worse financial toxicity was associated with income <$60,000 and living farther away from the hospital. Racial/ethnic minorities had higher rates of unanticipated medical costs. These data help to quantify the high financial burden for patients and may reveal a cause of disparities in clinical trial enrollment for underrepresented populations.

A Phase I Dose-Escalation Study to Evaluate the Safety and Tolerability of Evofosfamide in Combination with Ipilimumab in Advanced Solid Malignancies

PURPOSE

As hypoxia can mediate resistance to immunotherapy, we investigated the safety, tolerability, and efficacy of combining evofosfamide, a prodrug that alleviates hypoxia, with ipilimumab, an immune checkpoint inhibitor, in immunologically "cold" cancers, which are intrinsically insensitive to immunotherapy, as well as in "hot/warm" metastatic cancers that are, atypical of such cancers, resistant to immunotherapy.

PATIENTS AND METHODS

In a phase I, 3+3 dose-escalation trial (NCT03098160), evofosfamide (400-640 mg/m²) and ipilimumab (3 mg/kg) were administered in four 3-week cycles. The former was administered on days 1 and 8 of cycles 1-2, while the latter was administered on day 8 of cycles 1-4. Response was assessed using immune-related RECIST and retreatment was allowed, if deemed beneficial, after completion of cycle 4 or at progression.

RESULTS

Twenty-two patients were enrolled, of whom 21 were evaluable, encompassing castration-resistant prostate cancer (n = 11), pancreatic cancer (n = 7), immunotherapy-resistant melanoma (n = 2), and human papillomavirus-negative head and neck cancer (n = 1). Drug-related hematologic toxicities, rash, fever, nausea, vomiting, and elevation of liver enzymes were observed in > 10% of patients. The most common drug-related grade 3 adverse event was alanine aminotransferase elevation (33.3%). Two patients discontinued ipilimumab and 4 required evofosfamide deescalation due to toxicity. Of 18 patients with measurable disease at baseline, 3 (16.7%) achieved partial response and 12 (66.7%) achieved stable disease. The best responses were observed at 560 mg/m² evofosfamide. Preexisting immune gene signatures predicted response to therapy, while hypermetabolic tumors predicted progression. Responders also showed improved peripheral T-cell proliferation and increased intratumoral T-cell infiltration into hypoxia.

CONCLUSIONS

No new or unexpected safety signals were observed from combining evofosfamide and ipilimumab, and evidence of therapeutic activity was noted.

Combining Neratinib with CDK4/6, mTOR, and MEK Inhibitors in Models of HER2-positive Cancer

PURPOSE

Neratinib is an irreversible, pan-HER tyrosine kinase inhibitor that is FDA approved for HER2-overexpressing/amplified (HER2+) breast cancer. In this preclinical study, we explored the efficacy of neratinib in combination with inhibitors of downstream signaling in HER2+ cancers in vitro and in vivo.

EXPERIMENTAL DESIGN

Cell viability, colony formation assays, and Western blotting were used to determine the effect of neratinib in vitro. In vivo efficacy was assessed with patient-derived xenografts (PDX): two breast, two colorectal, and one esophageal cancer (with HER2 mutations). Four PDXs were derived from patients who received previous HER2-targeted therapy. Proteomics were assessed through reverse phase protein arrays and network-level adaptive responses were assessed through Target Score algorithm.

RESULTS

In HER2+ breast cancer cells, neratinib was synergistic with multiple agents, including mTOR inhibitors everolimus and sapanisertib, MEK inhibitor trametinib, CDK4/6 inhibitor palbociclib, and PI3Kα inhibitor alpelisib. We tested efficacy of neratinib with everolimus, trametinib, or palbociclib in five HER2+ PDXs. Neratinib combined with everolimus or trametinib led to a 100% increase in median event-free survival (EFS; tumor doubling time) in 25% (1/4) and 60% (3/5) of models, respectively, while neratinib with palbociclib increased EFS in all five models. Network analysis of adaptive responses demonstrated upregulation of EGFR and HER2 signaling in response to CDK4/6, mTOR, and MEK inhibition, possibly providing an explanation for the observed synergies with neratinib.

CONCLUSIONS

Taken together, our results provide strong preclinical evidence for combining neratinib with CDK4/6, mTOR, and MEK inhibitors for the treatment of HER2+ cancer.

Pembrolizumab in Patients with Advanced Metastatic Germ Cell Tumors

LESSONS LEARNED

Advanced germ cell tumors are aggressive and associated with poor prognosis. Pembrolizumab was overall well tolerated in 12 heavily pretreated patients. Three patients had radiographic stable disease that lasted for 10.9 months, 5.5 months, and 4.5 months, respectively. Published data of immunotherapeutic agents in patients with advanced germ cell tumors are confirmed. The limited antitumor activity of immunotherapy in germ cell tumors is, at least partially, attributed to tumor biology (low tumor mutational burden; low PD-1 expression) and other poor-risk features. Tumor profiling to understand the mechanisms of resistance to pembrolizumab and innovative clinical trials that may include immunotherapy are warranted.

BACKGROUND

Advanced germ cell tumors are associated with poor prognosis. We investigated the role of pembrolizumab in patients with advanced germ cell tumors.

METHODS

We analyzed a prespecified cohort of an open-label, phase II clinical trial in which patients with advanced germ cell tumors were treated with pembrolizumab (200 mg) intravenously every 21 days. The endpoints of the study were the non-progression rate (NPR) at 27 weeks, safety, and tolerability. An NPR >20% was considered successful and worthy of further pursuit.

RESULTS

From August 2016 to February 2018, 12 patients (10 men, 2 women) were treated (median age, 35 years [range, 22-63 years]; median number of prior systemic therapies, 3.5 [range, 2-7]; median number of metastatic sites, 3 [range, 2-8]). Overall, pembrolizumab was well tolerated. One patient experienced both grade 1 immune-related skin rash and grade 3 immune-related pneumonitis. No patient died from toxicity. Three patients had radiographic stable disease that lasted for 10.9 months, 5.5 months, and 4.5 months, respectively. No objective response was noted. The median progression-free survival was 2.4 months (95% confidence interval [CI], 1.5-4.5 months), and the median overall survival was 10.6 months (95% CI, 4.6-27.1 months). The 27-week NPR was 9.0% (95% CI, 0.23-41.2%).

CONCLUSION

Overall, pembrolizumab was safe and had limited antitumor activity in these patients. In the advanced, metastatic setting, tumor profiling to understand the mechanisms of resistance to immunotherapy and innovative clinical trials to identify efficacious combination regimens rather than off-label use of pembrolizumab are warranted.

Molecular Profiling of Metastatic Bladder Cancer Early-Phase Clinical Trial Participants Predicts Patient Outcomes

Prognosis for patients with metastatic bladder carcinoma (mBC) remains limited and in need of novel therapies. We retrospectively analyzed medical records of 43 patients with platinum-refractory metastatic bladder cancer (mBC) who participated in one or more phase I trials of various investigational therapies. Patients' tumors or circulating tumor DNA were analyzed by next-generation sequencing. The median progression-free survival was 4.2 months, the median overall survival was 9.6 months, and the overall response rate was 17.5%. TP53, ERBB2, PI3KCA, FGFR3, and ARID1A alterations were detected in 66%, 29%, 27%, 24%, and 22% of all patients, respectively. Alterations in FGFR3 were almost mutually exclusive of TP53. More than half (64%) of patients with an FGFR alt received an FGFR inhibitor, 67% of which achieved disease control. Among patients with urothelial carcinoma histology, those harboring a TP53 alteration had a shorter median progression-free survival (PFS) compared with those whose tumors carry wild-type TP53. The reverse relationship was observed in patients harboring an FGFR alteration. IMPLICATIONS: Patients with platinum-refractory mBC derive clinical benefit from participating in early-phase clinical trials and their survival outcomes correlate with the genetic profile of the tumor. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/19/3/395/F1.large.jpg.

Abstract PO-208: Patient-reported out-of-pocket costs and financial toxicity during early- phase oncology clinical trials

Background Clinical trials are an important therapeutic option for cancer patients (pts). Although financial burden in cancer treatment is well-documented, the financial burden associated with clinical trials is not well understood, especially for pts with lower income. Methods We conducted a survey regarding economic burden and financial toxicity in cancer pts who had been on Phase I clinical trials for ≥1 month. Financial Toxicity Score (FTS) was assessed using the validated COmprehensive Score for Financial Toxicity (COST) survey (scale 0-44, lower scores indicate worse toxicity). Pts also reported monthly out-of-pocket (OOP) medical and non-medical expenses. We applied multivariable logistic regression to analyze risk of financial toxicity, and unanticipated expenses. Results Early-phase clinical trial pts (N=213, median age = 59y; 59% female; 74% White, 45% w/ annual income ≤$60K; 54% had employer sponsored insurance; 37% had Medicare; 50% lived &gt;300 miles from the clinic; 37% required air travel) had a median FTS of 20, with interquartile range of 12. Median monthly OOP costs for non-medical expenses was $1075, and for medical expenses was $475. Median total monthly OOP costs was $1750. 55% and 64% of pts reported that actual medical and non-medical expenses were higher than expected, respectively. Worse financial toxicity (≤ median FTS) in pts was associated with yearly household income &lt;$60K (OR: 2.7, P=0.008), having medical costs higher than expected (OR: 3.2, P=0.024), participation on ≥1 Phase I clinical trial prior to their current trial (OR: 2.2, P=0.028), and living &gt;100 miles away from the clinical trials hospital (OR: 2.3, P=0.043). 29% of pts received partial/full reimbursement of clinical trial-related travel costs from study sponsor/other/insurance. Racial/ethnic minority (OR: 2.6, P=0.008) and pts who were unemployed or not working outside the home (OR: 2.4, P=0.023) were more likely to report that actual medical costs were much higher than expected. 53% of pts used savings and 19% borrowed money from friends/family or had a personal fundraiser to pay for treatment. Conclusions Among cancer pts participating on clinical trials, economic burden is high, and most of pts’ OOP costs were on non- medical expenses. Financial toxicity is disproportionally higher in pts with lower income and those who travel farther, and unexpected medical costs were more common among minorities. OOP costs can be substantial and are often unexpected for pts. Future work should focus on methods to reduce disparities in clinical trial participation, including the role of reimbursement of trial-related expenses.

Citation Format: Ryan W. Huey, Goldy C. George, Penny Phillips, Revenda White, Filip Janku, Daniel D. Karp, Aung Naing, Sarina Piha-Paul, Vivek Subbiah, Apostolia M. Tsimberidou, Shubham Pant, Timothy A. Yap, Jordi Rodon, Funda Meric-Bernstam, Ya-Chen Tina Shih, David S. Hong. Patient-reported out-of-pocket costs and financial toxicity during early- phase oncology clinical trials [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-208.

Validation of prognostic scoring systems for patients with metastatic renal cell carcinoma enrolled in phase I clinical trials

BACKGROUND

For patients with metastatic renal cell carcinoma (mRCC) who progress on standard-of-care therapies, there is an unmet need for novel treatments. Phase I clinical trials are designed to test the safety, toxicity and optimal dosing of novel agents. Herein, we analysed the outcomes of patients with mRCC enrolled in phase I trials and assess the utility of prognostic scores.

METHODS

Patients with all histologies of mRCC were included if they received treatment on a phase I clinical trial at MD Anderson Cancer Center (MDACC). Survival outcomes were calculated using Cox proportional hazard model. Prognostic value of the International Metastatic RCC Database Consortium (IMDC), Royal Marsden Hospital (RMH) and MDACC scores was assessed using the likelihood ratio (LR) χ² test and the c-index.

RESULTS

Among 82 patients with mRCC who received treatment, 21 patients participated in more than one trial, resulting in 106 trial participants (TP). Median prior therapies was two. For all TPs, median overall survival (OS) was 31.2 months, progression-free survival (PFS) was 5.9 months and objective response rate was 22%. Median OS and PFS were significantly shorter with increasing IMDC, RMH and MDACC scores. The RMH and MDACC scores outperformed the IMDC score for predicting OS (RMH LR χ²=8.64; MDACC LR χ²=7.74; IMDC LR χ²=2.36) and PFS (RMH LR χ²=17.5; MDACC LR χ²=20.3; IMDC LR χ²=4.28).

CONCLUSIONS

The RMH and MDACC prognostic scores can be used to predict OS for patients with mRCC in phase I trials and may guide patient selection. Patients with mRCC should be considered for phase I trials.

Abstract P1-19-08: Neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer: Updated results from the phase 2 SUMMIT ‘basket’ trial

Background: HER2 mutations define a subset of metastatic breast cancers (MBCs) with a unique mechanism of oncogenic addiction to HER2 signaling. Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, has been shown to have encouraging clinical activity when combined with fulvestrant in HER2-mutant, hormone receptor-positive (HR+) MBC [Smyth et al. SABCS 2018]. Genomic analyses suggest that acquired resistance to neratinib may occur by the acquisition of additional HER2 alterations, which may amplify HER2 pathway signaling [Won et al. AACR 2019]. We therefore explored whether dual HER2-targeted therapy may improve clinical benefit in this setting. Here we describe initial results from a cohort of patients with HER2-mutant, HR+ MBC treated with neratinib + trastuzumab + fulvestrant (N+T+F) from the phase 2 SUMMIT ‘basket’ trial (NCT01953926). Methods: Patients with HR+ MBC and known oncogenic driver HER2 mutations identified by genomic sequencing were eligible to receive combination treatment with oral neratinib 240 mg daily, intravenous trastuzumab 8 mg/kg initially followed by 6 mg/kg every 3 weeks, and intramuscular fulvestrant 500 mg on days 1 and 15 of month 1, then on day 1 every 4 weeks (N+T+F). Loperamide prophylaxis was mandatory during cycle 1. There was no restriction on the number of prior lines of systemic treatment for MBC. Efficacy endpoints included: confirmed objective response rate and clinical benefit rate - all defined according to RECIST v1.1 - as well as duration of response and progression-free survival. Genomic profiling from fresh/archival tumor tissues and/or plasma cfDNA was performed retrospectively by next-generation sequencing (MSK-IMPACT). Results: As of 01-May-2019, 19 patients were enrolled into the N+T+F cohort and received study treatment (safety population). 20 HER2 mutations were identified in the 19 patients: 14 kinase domain missense mutations, 3 extracellular domain missense mutations, and 3 exon-20 insertion mutations. Median number of prior systemic regimens for metastatic disease was 4 (range 0-10) and histologies were evenly split between lobular and ductal carcinomas. While the majority of patients remain on study treatment (n=15), only 13 of the 19 enrolled patients are efficacy evaluable at this time (having had ≥1 post-baseline tumor assessment). Clinical activity is summarized in the Table. Diarrhea was the most commonly reported adverse event (84.2% any grade) with 5 patients reporting Grade 3 diarrhea (there were no Grade 4 diarrhea events). Three patients (15.8%) reduced neratinib dose due to diarrhea but no patient discontinued treatment due to diarrhea. Conclusions: The combination of N+T+F resulted in an encouraging response rate and was a well-tolerated regimen in predominantly heavily pretreated HER2-mutant HR+ breast cancers. Based on a pre-planned interim analysis, the cohort has been expanded to enroll a total of 50 patients. Updated efficacy and safety data will be presented.

Neratinib + trastuzumab + fulvestrant(n=13)Confirmed objective response rate, % (95% CI)39 (13.9-68.4)Complete response0Partial response5 (39)Duration of responses range, months4.2*-10.4*Median progression-free survivala,b, months (95% CI)NA (1.9-NA)*Response ongoing; aKaplan-Meier analysis; bincludes all patients enrolled (n=19); NA, not applicable.

Citation Format: Hans Wildiers, Valentina Boni, Cristina Saura, Mafalda Oliveira, Komal Jhaveri, Helen Won, François-Clément Bidard, Adam M Brufsky, Mark E Burkard, Andrés Cervantes, Carlos Fernández-Martos, Barbara Haley, Sherene Loi, Iben Spanggaard, Stefano Panni, Janice Lu, Melanie E Dujka, Feng Xu, Sonia Macia, Lisa D Eli, Alshad S Lalani, Sarina Piha-Paul, Funda Meric-Bernstam, David B Solit, David M Hyman. Neratinib + trastuzumab + fulvestrant for HER2-mutant, hormone receptor-positive, metastatic breast cancer: Updated results from the phase 2 SUMMIT ‘basket’ trial [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 P1-19-08.

Long-term overall survival and prognostic score predicting survival: the IMPACT study in precision medicine

Background

In 2007, we initiated IMPACT, a precision medicine program for patients referred for participation in early-phase clinical trials. We assessed the correlation of factors, including genomically matched therapy, with overall survival (OS).

Patients and methods

We performed molecular profiling (Clinical Laboratory Improvement Amendments) (genes ≤ 182) for patients with lethal/refractory advanced cancers referred to the Phase 1 Clinical Trials Program. Matched therapy, if available, was selected on the basis of genomics. Clinical trials varied over time and included investigational drugs against various targets (single agents or combinations). Patients were followed up for up to 10 years.

Results

Of 3487 patients who underwent tumor molecular profiling, 1307 (37.5%) had ≥ 1 alteration and received therapy (matched, 711; unmatched, 596; median age, 57 years; 39% men). Most common tumors were gastrointestinal, gynecologic, breast, melanoma, and lung. Objective response rates were: matched 16.4%, unmatched 5.4% (p < .0001); objective response plus stable disease ≥ 6 months rates were: matched 35.3% and unmatched 20.3%, (p < .001). Respective median progression-free survival: 4.0 and 2.8 months (p < .0001); OS, 9.3 and 7.3 months; 3-year, 15% versus 7%; 10-year, 6% vs. 1% (p < .0001). Independent factors associated with shorter OS (multivariate analysis) were performance status > 1 (p < .001), liver metastases (p < .001), lactate dehydrogenase levels > upper limit of normal (p < .001), PI3K/AKT/mTOR pathway alterations (p < .001), and non-matched therapy (p < .001). The five independent factors predicting shorter OS were used to design a prognostic score.

Conclusions

Matched targeted therapy was an independent factor predicting longer OS. A score to predict an individual patient’s risk of death is proposed.

Trial registration

ClinicalTrials.gov, NCT00851032, date of registration February 25, 2009.

A Deep Learning Framework for Predicting Response to Therapy in Cancer

A major challenge in cancer treatment is predicting clinical response to anti-cancer drugs on a personalized basis. Using a pharmacogenomics database of 1,001 cancer cell lines, we trained deep neural networks for prediction of drug response and assessed their performance on multiple clinical cohorts. We demonstrate that deep neural networks outperform the current state in machine learning frameworks. We provide a proof of concept for the use of deep neural network-based frameworks to aid precision oncology strategies.

Pembrolizumab in patients with programmed death ligand 1-positive advanced ovarian cancer: Analysis of KEYNOTE-028

OBJECTIVE

To evaluate safety, tolerability, and antitumor activity of pembrolizumab monotherapy in patients with programmed death ligand 1 (PD-L1)-expressing advanced ovarian cancer enrolled in the multicohort, phase Ib KEYNOTE-028 trial.

METHODS

Key inclusion criteria were age ≥18 years; advanced ovarian epithelial, fallopian tube, or primary peritoneal carcinoma; failure of previous therapy; and tumor PD-L1 positivity. Patients received pembrolizumab (10 mg/kg every 2 weeks) for ≤24 months or until disease progression/intolerable toxicity. Tumor response was assessed per RECIST v1.1 (investigator review). Adverse events (AEs) were graded using CTCAE version 4.0. Primary end point was confirmed objective response rate (ORR) per RECIST v1.1 (investigator review); data cutoff date was February 20, 2017.

RESULTS

Twenty-six patients (median age, 57.5 years) with PD-L1-positive advanced metastatic ovarian cancer received pembrolizumab; 38.5% had metastatic disease, and 73.1% previously received ≥3 lines of therapy. Treatment-related AEs (TRAEs) occurred in 19 (73.1%) patients, most commonly arthralgia (19.2%), nausea (15.4%), and pruritus (15.4%). One grade 3 TRAE (increased plasma transaminase level) occurred. No deaths and no treatment discontinuations due to TRAEs occurred. After a median follow-up duration of 15.4 months, ORR was 11.5% (1 complete response, 2 partial responses); 7 patients (26.9%) achieved stable disease. Median progression-free and overall survival were 1.9 (95% CI, 1.8-3.5) and 13.8 (95% CI, 6.7-18.8) months, respectively.

CONCLUSION

Pembrolizumab conferred durable antitumor activity with manageable safety and toxicity in patients with advanced PD-L1-positive ovarian cancer and is under further investigation in an ongoing phase II trial, KEYNOTE-100.

STAT3 antisense oligonucleotide AZD9150 in a subset of patients with heavily pretreated lymphoma: results of a phase 1b trial

Background

The Janus kinase (JAK) and signal transduction and activation of transcription (STAT) signaling pathway is an attractive target in multiple cancers. Activation of the JAK-STAT pathway is important in both tumorigenesis and activation of immune responses. In diffuse large B-cell lymphoma (DLBCL), the transcription factor STAT3 has been associated with aggressive disease phenotype and worse overall survival. While multiple therapies inhibit upstream signaling, there has been limited success in selectively targeting STAT3 in patients. Antisense oligonucleotides (ASOs) represent a compelling therapeutic approach to target difficult to drug proteins such as STAT3 through of mRNA targeting. We report the evaluation of a next generation STAT3 ASO (AZD9150) in a non-Hodgkin’s lymphoma population, primarily consisting of patients with DLBCL.

Methods

Patients with relapsed or treatment refractory lymphoma were enrolled in this expansion cohort. AZD9150 was administered at 2 mg/kg and the 3 mg/kg (MTD determined by escalation cohort) dose levels with initial loading doses in the first week on days 1, 3, and 5 followed by weekly dosing. Patients were eligible to remain on therapy until unacceptable toxicity or progression. Blood was collected pre- and post-treatment for analysis of peripheral immune cells.

Results

Thirty patients were enrolled, 10 at 2 mg/kg and 20 at 3 mg/kg dose levels. Twenty-seven patients had DLBCL. AZD9150 was safe and well tolerated at both doses. Common drug-related adverse events included transaminitis, fatigue, and thrombocytopenia. The 3 mg/kg dose level is the recommended phase 2 dose. All responses were seen among DLBCL patients, including 2 complete responses with median duration of response 10.7 months and 2 partial responses. Peripheral blood cell analysis of three patients without a clinical response to therapy revealed a relative increase in proportion of macrophages, CD4+, and CD8+ T cells; this trend did not reach statistical significance.

Conclusions

AZD9150 was well tolerated and demonstrated efficacy in a subset of heavily pretreated patients with DLBCL. Studies in combination with checkpoint immunotherapies are ongoing.

Trial registration

Registered at ClinicalTrials.gov: NCT01563302. First submitted 2/13/2012.

Electronic supplementary material

The online version of this article (10.1186/s40425-018-0436-5) contains supplementary material, which is available to authorized users.

Outcome analysis of Phase I trial patients with metastatic KRAS and/or TP53 mutant non-small cell lung cancer

KRAS and TP53 mutations, which are the most common genetic drivers of tumorigenesis, are still considered undruggable targets. Therefore, we analyzed these genetic aberrations in metastatic non-small cell lung cancer (NSCLC) for the development of potential therapeutics. One hundred eighty-five consecutive patients with metastatic NSCLC in a phase 1 trial center were included. Their genomic aberrations, clinical characteristics, survivals, and phase 1 trial therapies were analyzed. About 10%, 18%, 36%, and 36% of the patients had metastatic KRAS+/TP53+, KRAS+/TP53-,KRAS-/TP53+, and KRAS-/TP53- NSCLC, respectively. The most common concurrent genetic aberrations beside KRAS and/or TP53 (>5%) were KIT, epidermal growth factor receptor, PIK3CA, c-MET, BRAF, STK11, ATM, CDKN2A, and APC. KRAS+/TP53+ NSCLC did not respond well to the phase 1 trial therapy and was associated with markedly worse progression-free (PFS) and overall (OS) survivals than the other three groups together. KRAS hotspot mutations at locations other than codon G12 were associated with considerably worse OS than those at this codon. Gene aberration-matched therapy produced prolonged PFS and so was anti-angiogenesis in patients with TP53 mutations. Introduction of the evolutionary action score system of TP53 missense mutations enabled us to identify a subgroup of NSCLC patients with low-risk mutant p53 proteins having a median OS duration of 64.5 months after initial diagnosis of metastasis. These data suggested that patients with metastatic dual KRAS+/TP53+ hotspot-mutant NSCLC had poor clinical outcomes. Further analysis identified remarkably prolonged survival in patients with low-risk mutant p53 proteins, which warrants confirmatory studies.

Cytokines Produced by Dendritic Cells Administered Intratumorally Correlate with Clinical Outcome in Patients with Diverse Cancers

Purpose: Dendritic cells (DC) initiate adaptive immune responses through the uptake and presentation of antigenic material. In preclinical studies, intratumorally injected activated DCs (aDCs; DCVax-Direct) were superior to immature DCs in rejecting tumors from mice.Experimental Design: This single-arm, open-label phase I clinical trial evaluated the safety and efficacy of aDCs, administered intratumorally, in patients with solid tumors. Three dose levels (2 million, 6 million, and 15 million aDCs per injection) were tested using a standard 3 + 3 dose-escalation trial design. Feasibility, immunogenicity, changes to the tumor microenvironment after direct injection, and survival were evaluated. We also investigated cytokine production of aDCs prior to injection.Results: In total, 39 of the 40 enrolled patients were evaluable. The injections of aDCs were well tolerated with no dose-limiting toxicities. Increased lymphocyte infiltration was observed in 54% of assessed patients. Stable disease (SD; best response) at week 8 was associated with increased overall survival. Increased secretion of interleukin (IL)-8 and IL12p40 by aDCs was significantly associated with survival (P = 0.023 and 0.024, respectively). Increased TNFα levels correlated positively with SD at week 8 (P < 0.01).Conclusions: Intratumoral aDC injections were feasible and safe. Increased production of specific cytokines was correlated with SD and prolonged survival, demonstrating a link between the functional profile of aDCs prior to injection and patient outcomes. Clin Cancer Res; 24(16); 3845-56. ©2018 AACR.

Abstract CT024: Results of a phase I dose escalation study of ARQ 751 in adult subjects with advanced solid tumors with AKT1, 2, 3 genetic alterations, activating PI3K mutations, PTEN-null, or other known actionable PTEN mutations

Background: Dysregulation of the PI3K-AKT signaling pathway is associated with a number of cancers. and plays a critical role in cancer initiation and progression. AKT can be activated through activated receptor tyrosine kinases, gain-of-function mutations of PIK3CA, PTEN deficiency, and AKT amplification or activating mutations such as AKT1E17K. As the second generation of allosteric AKT inhibitor, ARQ 751 potently inhibits AKT1, 2 and 3 with biochemical IC50 values of 0.55 nM, 0.81 nM and 1.31 nM receptively. In addition, ARQ 751 is very selective; it does not inhibit any other kinase (out of the 245 tested) by greater than 50% at 5 µM. The objective of this study is to determine maximum tolerated dose in patients with advanced solid tumors.

Material and Methods: This is Phase 1 Dose Escalation Study to assess the safety and tolerability of ARQ 751 in subjects with advanced solid tumors with AKT1, 2, 3 genetic alterations, activating PI3K mutations, PTEN-null, or other known actionable PTEN mutations. Treatment emerging adverse events (TEAE) were assessed per NCI CTCAE v. 4.03. Tumor response were evaluated per RECIST 1.1. Blood samples were collected for PK.

Results: A total of 15 pts have been enrolled [73% female; median age 61 years; 5 Breast (5), endometrial (2), and others (9); activating PI3K mutation (9), PTEN null/other known actionable PTEN mutations (5), AKT 1 mutation (1)] and treated at dose levels of 5 mg QD, 10 mg QD, 20 mg QD, 25 mg QOD and 25 mg QD. There have been no DLTs reported so far. ARQ 751 related TEAEs included nausea (27%), stomatitis, vomiting, fatigue, mucosal inflammation, white blood cell count decreased, hyperkalaemia, cough, oropharyngeal pain, sinus congestion, pain of skin, puritus and hot flushes (7% each). All these TEAEs were grade 1 or 2. There was no ≥ Grade 3 drug related TEAEs or any grade drug-related SAEs. Four pts achieved a best response of stable disease (SD) including 1 with breast cancer treated at 25 mg QOD for 42+ weeks, 1 with head and neck cancer treated at 20 mg QD for 16 weeks, 1 with breast cancer treated at 25 mg QD for 12+, and 1 with endometrial cancer treated at 25 mg QD for 10+ weeks. 3 of 4 SD pts are currently on therapy.

Conclusions: ARQ 751 demonstrated a manageable safety profile at Dose level up to 25 mg QD. The dose escalation is ongoing. PK and updated safety, efficacy data will be presented.

Citation Format: Shubham Pant, Vivek Subbiah, Jordi Rodon, Filip Janku, David Hong, Daniel Karp, Sarina Piha-Paul, Apostolia M. Tsimberidou, Aung Naing, Siqing Fu, Ron E. Savage, Feng Chai, Yi Yu, Brian Schwartz, Funda Meric-Bernstam, Tim Yap. Results of a phase I dose escalation study of ARQ 751 in adult subjects with advanced solid tumors with AKT1, 2, 3 genetic alterations, activating PI3K mutations, PTEN-null, or other known actionable PTEN mutations [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 CT024.

Clinical genomic profiling to identify actionable alterations for investigational therapies in patients with diverse sarcomas

Background

There are currently no United States Food and Drug Administration approved molecularly matched therapies for sarcomas except gastrointestinal stromal tumors. Complicating this is the extreme diversity, heterogeneity, and rarity of these neoplasms. Few therapeutic options exist for relapsed and refractory sarcomas. In clinical practice many oncologists refer patients for genomic profiling hoping for guidance on treatment options after standard therapy. However, a systematic analysis of actionable mutations has yet to be completed. We analyzed genomic profiling results in patients referred to MD Anderson Cancer Center with advanced sarcomas to elucidate the frequency of potentially actionable genomic alterations in this population.

Methods

We reviewed charts of patients with advanced sarcoma who were referred to investigational cancer therapeutics department and had CLIA certified comprehensive genomic profiling (CGP) of 236 or 315 cancer genes in at least 50ng of DNA. Actionable alterations were defined as those identifying anti-cancer drugs on the market, in registered clinical trials, or in the Drug-Gene Interaction Database.

Results

Among the 102 patients analyzed median age was 45.5 years (range 8-76), M: F ratio 48:54. The most common subtypes seen in our study were leiomyosarcoma (18.6%), dedifferentiated liposarcoma (11%), osteosarcoma (11%), well-differentiated liposarcoma (7%), carcinosarcoma (6%), and rhabdomyosarcoma (6%). Ninety-five out of 102 patients (93%) had at least one genomic alteration identified with a mean of six mutations per patient. Of the 95 biopsy samples with identifiable genomic alterations, the most commonly affected genes were TP53 (31.4%), CDK4 (23.5%), MDM2 (21.6%), RB1 (18.6%), and CDKN2A/B (13.7%). Notable co-segregating amplifications included MDM2-CDK4 and FRS2-FGF. Sixteen percent of patients received targeted therapy based on CGP of which 50% had at least stable disease.

Conclusions

Incorporating CGP into sarcoma management may allow for more precise diagnosis and sub-classification of this diverse and rare disease, as well as personalized matching of patients to targeted therapies such as those available in basket clinical trials.

Predicting outcomes in patients with advanced non-small cell lung cancer enrolled in early phase immunotherapy trials

OBJECTIVES

Immunotherapy (IO) has altered the non-small cell lung cancer (NSCLC) therapeutic landscape. However, the majority of patients do not respond to immune-checkpoint blockade, and subsequently either receive further chemotherapy or are referred for clinical trials. Here we examined the outcomes and predictors of response to IO in early phase clinical trials.

MATERIALS AND METHODS

We analyzed the records of 74 patients with metastatic NSCLC that were enrolled on phase 1 IO trials within MD Anderson Cancer Center from 1/2010 to 7/2017.

RESULTS

The median age was 68, with a median follow-up of 12.3 months. The median lines of prior therapy was three. There were 53 patients who did not receive any IO as a prior line of treatment with a mOS of 8.2 months and mPFS of 3.4 months. There were 21 patients who progressed on a prior IO agent and subsequently went on an IO study with a mOS of 10.5 months and mPFS of 4.3 months, which was similar to patients who did not receive IO OS HR 0.81 (P = .51) and PFS HR 0.85 (P = .59). Royal Marsden Hospital (RMH) prognostic score >1 was predictive of decreased OS HR 3.59 (P = .014) although PFS was not statistically different. MDACC prognostic score was predictive of both OS HR 3.39 (P = .0002) and PFS HR 1.9 (P = .030). ANC/ALC ratio (NLR) of >6 was predictive of decreased survival mOS 3.2 months compared to NLR <6 mOS 11 months; HR 3.0 (P = .0023).

CONCLUSIONS

In our heavily pretreated patient population with NSCLC, early phase clinical trials with IO demonstrated similar outcomes to those seen in larger clinical studies that also used immune checkpoint inhibitors. The addition of NLR to RMH and MDACC prognostic scores can identify patients with poor overall outcomes treated with early phase IO studies.

Clinical pharmacodynamic/exposure characterisation of the multikinase inhibitor ilorasertib (ABT-348) in a phase 1 dose-escalation trial

Background

Ilorasertib (ABT-348) inhibits Aurora and VEGF receptor (VEGFR) kinases. Patients with advanced solid tumours participated in a phase 1 dose-escalation trial to profile the safety, tolerability, and pharmacokinetics of ilorasertib.

Methods

Ilorasertib monotherapy was administered at 10–180 mg orally once daily (Arm I, n = 23), 40–340 mg orally twice daily (Arm II, n = 28), or 8–32 mg intravenously once daily (Arm III, n = 7), on days 1, 8, and 15 of each 28-day cycle.

Results

Dose-limiting toxicities were predominantly related to VEGFR inhibition. The most frequent treatment-emergent adverse events ( > 30%) were: fatigue (48%), anorexia (34%), and hypertension (34%). Pharmacodynamic markers suggested that ilorasertib engaged VEGFR2 and Aurora B kinase, with the VEGFR2 effects reached at lower doses and exposures than Aurora inhibition effects. In Arm II, one basal cell carcinoma patient (40 mg twice daily (BID)) and one patient with adenocarcinoma of unknown primary site (230 mg BID) had partial responses.

Conclusions

In patients with advanced solid tumours, ilorasertib treatment resulted in evidence of engagement of the intended targets and antitumour activity, but with maximum inhibition of VEGFR family kinases occurring at lower exposures than typically required for inhibition of Aurora B in tissue.

Clinical Trial Registration: NCT01110486

Development of a prognostic scoring system for patients with advanced cancer enrolled in immune checkpoint inhibitor phase 1 clinical trials

Background:

We sought to develop a prognostic scoring system to aid in patient selection for immune checkpoint inhibitor (ICI) phase 1 clinical trials.

Methods:

Clinical data from patients treated in phase 1 ICI clinical trials at MD Anderson (MDA) Center were analysed. Seventeen clinical factors were studied. Recursive partitioning analysis, a tree-based model, was used to develop a regression tree and identify optimal cut-points based on differences in survival for each clinical factor. A Cox proportional hazards regression model was then used to identify factors independently affecting overall survival. A prognostic scoring system was subsequently developed.

Results:

A total of 172 patients (105 CTLA4- and 67 PD1-based) were analysed. Seven factors were independently associated with worse overall survival (OS): age>52 years (hazard ratio (HR) 1.59, 95% confidence interval (CI) 1.1–2.4), Eastern Cooperative Oncology Group performance status>1 (HR 2.81, 95%CI 1.3–6.3), lactate dehydrogenase >466 (which is 0.75 × the upper limit of normal at our institution) (HR 2.1, 95% CI 1.4–3.2), platelet count >300 × 10³μL⁻¹ (HR 1.8, 95% CI 1.2–2.8), absolute neutrophil count >4.9 × 10³μL⁻¹ (HR 2.3, 95% CI 1.5–3.5), absolute lymphocyte count <1.8 × 10³μL⁻¹ (HR 3.3, 95% CI 1.9–5.7), and liver metastases (HR 1.8, 95% CI 1.2–2.6). An index was created by dividing the cohort into risk groups based on the number of factors present: 0–2, 3, 4, or 5–6. Median OS was 24.2 months, 11.6 months, 8.0 months, and 3.8 months for patients with 0–2, 3, 4, or 5–6 risk factors, respectively; log-rank test, P<0.0001. The Harrell c-index of this scoring system was 0.72, indicating better predictability than the Royal Marsden Hospital score (c-index 0.67) and MDA score (c-index 0.61).

Conclusions:

We have developed a novel ‘MDA-ICI’ prognostic scoring system for patients treated in phase 1 ICI clinical trials. Prospective evaluation and external validation is warranted and may help aid patient selection for future clinical trials.

Continuous anti-angiogenic therapy after tumor progression in patients with recurrent high-grade epithelial ovarian cancer: phase I trial experience

High-grade epithelial ovarian cancer (HG-EOC) is the most lethal gynecologic malignancy worldwide Once patients develop chemoresistance, effective novel strategies are required to improve prognosis We analyzed characteristics and outcomes of 242 consecutive patients with HG-EOC participating in 94 phase I clinical trials at The University of Texas MD Anderson Cancer Center. Baseline lactate dehydrogenase levels, albumin levels, and number of metastatic sites were independent predictors of overall survival (OS). Receiving more than 1 phase I protocol was associated with improved OS (p < 0.001). Regimens including a chemotherapeutic agent plus bevacizumab or Aurora A kinase inhibitor led to a median progression-free survival (PFS) duration of more than 6 months. Although patients receiving bevacizumab-based regimens in the phase I clinical trials had significantly longer PFS than those receiving other anti-angiogenic therapies (p = 0.017), patients treated with vascular endothelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs) had significantly longer OS (12.2 months) than those not treated with VEGFR-TKIs (8.6 months, p = 0.015).

In conclusion, anti-angiogenic therapy is one of the most important strategies for the treatment of HG-EOC, even in those who have already experienced tumor progression. Therefore, eligible patients with HG-EOC should be encouraged to participate in novel phase I studies of anti-angiogenic therapies, even after disease progression.

Abstract A167: Targeting HER2 (ERBB2) amplification identified by next-generation sequencing (NGS) in patients with advanced or metastatic solid tumors

Introduction: Personalized cancer treatment is becoming more tumor agnostic by choosing a treatment based on the tumor genomics rather than the tumor type. HER2 is an effective therapeutic target with FDA-approved treatments in breast and gastric/gastroesophageal junction (GEJ) cancers; however, less is known about the efficacy of HER2-targeted treatment in other tumor types. Methods: Next-generation sequencing (NGS) was performed in 2221 patients (pts) with advanced solid tumors in CLIA-certified laboratories using multiple platforms for personalized cancer therapy. HER2 amplification (amp) was assessed by NGS platforms that report copy-number variations as per their respective algorithm. We assessed clinical characteristics and coalterations with HER2 amp. We evaluated the clinical benefit of HER2-targeted therapy, by measuring the progression-free survival (PFS) on HER2-matched targeted therapy (PFS2) compared to the PFS on prior therapy (PFS1). We also evaluated the response rate and overall survival (OS) of pts who received vs pts who did not receive HER2-targeted therapy. Results: A total of 122 pts (5.5%) were found to have HER2 amp. The most frequent tumor types were colorectal, biliary/gallbladder, gastric/gastroesophageal, esophageal, endometrial, head and neck squamous cell and salivary gland, non-small cell lung, and bladder cancers. Coalterations included mutations in TP53, APC, PIK3CA, LRP1B, NF1, KRAS, mutations and deletions in CDKN2A, and amp in MYC and CCNE1. Frequent amp in CDK12, RARA, and TOP2A amp (all within chromosome 17q) were also found in our pts. Concurrent mutations in HER2 were found in 16 pts (13%). Forty pts with HER2 amp on NGS also underwent HER2 IHC testing: 30 pts (75%) had overexpression (3+), 4 pts (10%) had equivocal expression (2+), 2 pts (5%) had low expression (1+), and 4 pts (10%) had no HER2 expression. FISH analysis was performed in 14 patients, out of which 12 patients were positive for amplification. Forty-four of 115 pts received at least 1 line of HER2-targeted therapy (range 1-4) with 42 pts receiving trastuzumab in combination with other drugs, including 11 (92%) of 12 pts with gastric, GEJ cancers with HER2 amp having received trastuzumab with chemotherapy (8 pts in the first line). Median OS of pts who received HER2-targeted therapy was 42 months vs 23 months for pts who did not receive HER2-targeted therapy (Hazard Ratio [HR] 0.6, 95% CI 0.38-0.97, p=0.0384). For 32 evaluable pts, PFS2/PFS1 ratio was ≥1.3 in 17 pts (53%) and ≥2 in 11 pts (34%) with median PFS2 of 23 weeks vs PFS1 of 11 weeks (p=0.0089). After exclusion of pts with gastric or GEJ cancers, pts receiving HER2-targeted therapy still had an improved OS (53 vs 23 months) (HR 0.56, 95% CI 0.33-0.93, p=0.0307) and the PFS2/PFS1 ratio was ≥1.3 in 15 (52%) of 29 pts with a median PFS2 of 23 weeks vs PFS1 of 12 weeks (p=0.0174). Conclusion: NGS reveals HER2 amp in a clinically relevant proportion of tumors and in a variety of tumor types. HER2-targeted therapy may confer clinical benefit in tumor types beyond those for which HER2 inhibitors are approved. The association of HER2 amp with genomic alterations in other oncogenic drivers provides rationale for novel therapeutic combinations.

Citation Format: Ecaterina Ileana Dumbrava, Kavitha Balaji, Kanwal Raghav, Milind Javle, Mariela Blum-Murphy, Blessy Sajan, Scott Kopetz, Russell Broaddus, Mark Routbort, Shubham Pant, Apostolia Tsimberidou, Vivek Subbiah, David S. Hong, Jordi Rodon Ahnert, Kenna Shaw, Sarina Piha-Paul, Funda Meric-Bernstam. Targeting HER2 (ERBB2) amplification identified by next-generation sequencing (NGS) in patients with advanced or metastatic solid tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A167.

Characteristics and outcomes of patients with advanced sarcoma enrolled in early phase immunotherapy trials

Background

Immunotherapies, specifically those based on immune checkpoint inhibitors, have shown promising activity in multiple tumor types. Other than mifamurtide (MEPACT®) for osteosarcoma approved by European Medicines Agency, there are no approved immunotherapies for sarcomas.

Methods

We analyzed medical records of patients with advanced sarcoma who were referred to Phase 1 clinic at MD Anderson and received an immunotherapy (checkpoint inhibitors, vaccines, or cytokine based therapies). Clinical parameters including demographics, clinical history, toxicity, and response were abstracted.

Results

Among 50 patients enrolled in immunotherapy trials (Bone 10; Soft-tissue 40) we found 14 different subtypes of sarcomas. Royal Marsden Hospital (RMH) prognostic score was <2 (86%). Performance status (PS) was 0–1 in 48 patients (96%); median number of prior therapies was 3 (0–12). Immunotherapy consisted of checkpoint inhibitors (82%: PD1 = 7, PD-L1 = 11, CTLA4 = 22, other = 1) of which 42% were combinations, as well as vaccines (14%), and cytokines (4%). Median overall survival (OS) was 13.4 months (11.2 months: not reached). Median progression free survival (PFS) was 2.4 months (95% CI = 1.9–3.2 months). Best response was partial response (PR) in 2 patients with alveolar soft part sarcoma (ASPS) and stable disease (SD) in 11 patients (3 GIST, 3 liposarcomas (2 DDLS, 1 WDLS), 2 ASPS, 2 leiomyo, 1 osteo). PFS was 34% (23%, at 50%) at 3 months, 16% (8%, 30%) at 6 months, and 6% (2%, 20%) at 1 year. Pseudo-progression followed by stable disease was observed in 2 patients (4%). Grade 3/4 adverse events included rash (10%), fever (6%), fatigue (6%), and nausea/vomiting (6%).

Conclusion

Immunotherapies were well tolerated in advanced sarcoma patients enrolled in trials. All four ASPS patients had clinical benefit with checkpoint inhibitors and this was the only subtype experiencing partial response. Further evaluation of checkpoint inhibitors in ASPS is warranted.

Clinical Use of Precision Oncology Decision Support

PURPOSE

Precision oncology is hindered by the lack of decision support for determining the functional and therapeutic significance of genomic alterations in tumors and relevant clinically available options. To bridge this knowledge gap, we established a Precision Oncology Decision Support (PODS) team that provides annotations at the alteration-level and subsequently determined if clinical decision-making was influenced.

METHODS

Genomic alterations were annotated to determine actionability based on a variant's known or potential functional and/or therapeutic significance. The medical records of a subset of patients annotated in 2015 were manually reviewed to assess trial enrollment. A web-based survey was implemented to capture the reasons why genotype-matched therapies were not pursued.

RESULTS

PODS processed 1,669 requests for annotation of 4,084 alterations (2,254 unique) across 49 tumor types for 1,197 patients. 2,444 annotations for 669 patients included an actionable variant call: 32.5% actionable, 9.4% potentially, 29.7% unknown, 28.4% non-actionable. 66% of patients had at least one actionable/potentially actionable alteration. 20.6% (110/535) patients annotated enrolled on a genotype-matched trial. Trial enrolment was significantly higher for patients with actionable/potentially actionable alterations (92/333, 27.6%) than those with unknown (16/136, 11.8%) and non-actionable (2/66, 3%) alterations (p=0.00004). Actionable alterations in PTEN, PIK3CA, and ERBB2 most frequently led to enrollment on genotype-matched trials. Clinicians cited a variety of reasons why patients with actionable alterations did not enroll on trials.

CONCLUSION

Over half of alterations annotated were of unknown significance or non-actionable. Physicians were more likely to enroll a patient on a genotype-matched trial when an annotation supported actionability. Future studies are needed to demonstrate the impact of decision support on trial enrollment and oncologic outcomes.

Initiative for Molecular Profiling and Advanced Cancer Therapy (IMPACT): An MD Anderson Precision Medicine Study

PURPOSE

Genomic profiling is increasingly used in the management of cancer. We have previously reported preliminary results of our precision medicine program. Here, we present response and survival outcomes for 637 additional patients who were referred for phase I trials and were treated with matched targeted therapy (MTT) when available.

PATIENTS AND METHODS

Patients with advanced cancer who underwent tumor genomic analyses were treated with MTT when available.

RESULTS

Overall, 1,179 (82.1%) of 1,436 patients had one or more alterations (median age, 59.7 years; men, 41.2%); 637 had one or more actionable aberrations and were treated with MTT (n = 390) or non-MTT (n = 247). Patients who were treated with MTT had higher rates of complete and partial response (11% v 5%; P = .0099), longer failure-free survival (FFS; 3.4 v 2.9 months; P = .0015), and longer overall survival (OS; 8.4 v 7.3 months; P = .041) than did unmatched patients. Two-month landmark analyses showed that, for MTT patients, FFS for responders versus nonresponders was 7.6 versus 4.3 months (P < .001) and OS was 23.4 versus 8.5 months (P < .001), whereas for non-MTT patients (responders v nonresponders), FFS was 6.6 versus 4.1 months (P = .001) and OS was 15.2 versus 7.5 months (P = .43). Patients with phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase pathway alterations matched to PI3K/Akt/mammalian target of rapamycin axis inhibitors alone demonstrated outcomes comparable to unmatched patients.

CONCLUSION

Our results support the use of genomic matching. Subset analyses indicate that matching patients who harbor a PI3K and mitogen-activated protein kinase pathway alteration to only a PI3K pathway inhibitor does not improve outcome. We have initiated IMPACT2, a randomized trial to compare treatment with and without genomic selection.