Pembrolizumab Plus mFOLFOX7 or FOLFIRI for Microsatellite Stable/Mismatch Repair-Proficient Metastatic Colorectal Cancer: KEYNOTE-651 Cohorts B and D.

BACKGROUND: The phase 1b KEYNOTE-651 study evaluated pembrolizumab plus chemotherapy in microsatellite stable or mismatch repair-proficient metastatic colorectal cancer. PATIENTS AND METHODS: Patients with microsatellite stable or mismatch repair-proficient metastatic colorectal cancer received pembrolizumab 200 mg every 3 weeks plus 5-fluorouracil, leucovorin, oxaliplatin (previously untreated; cohort B) or 5-fluorouracil, leucovorin, irinotecan (previously treated with fluoropyrimidine plus oxaliplatin; cohort D) every 2 weeks. Primary end point was safety; investigator-assessed objective response rate per RECIST v1.1 was secondary and biomarker analysis was exploratory. RESULTS: Thirty-one patients were enrolled in cohort B and 32 in cohort D; median follow-up was 30.2 and 33.5 months, respectively. One dose-limiting toxicity (grade 3 small intestine obstruction) occurred in cohort D. In cohort B, grade 3 or 4 treatment-related adverse events (AEs) occurred in 18 patients (58%), most commonly neutropenia and decreased neutrophil count (n = 5 each). In cohort D, grade 3 or 4 treatment-related AEs occurred in 17 patients (53%), most commonly neutropenia (n = 7). No grade 5 treatment-related AEs occurred. Objective response rate was 61% in cohort B (KRAS wildtype: 71%; KRAS mutant: 53%) and 25% in cohort D (KRAS wildtype: 47%; KRAS mutant: 6%). In both cohorts, PD-L1 combined positive score and T-cell-inflamed gene expression profiles were higher and HER2 expression was lower in responders than nonresponders. No association between tumor mutational burden and response was observed. CONCLUSION: Pembrolizumab plus 5-fluorouracil, leucovorin, oxaliplatin/5-fluorouracil, leucovorin, irinotecan demonstrated an acceptable AE profile. Efficacy data appeared comparable with current standard of care (including by KRAS mutation status). Biomarker analyses were hypothesis-generating, warranting further exploration. GOV IDENTIFIER: ClinicalTrials.gov; NCT03374254.

Pembrolizumab Plus Binimetinib With or Without Chemotherapy for MSS/pMMR Metastatic Colorectal Cancer: Outcomes From KEYNOTE-651 Cohorts A, C, and E.

BACKGROUND: Cohorts A, C, and E of the phase Ib KEYNOTE-651 study evaluated pembrolizumab + binimetinib ± chemotherapy in microsatellite stable/mismatch repair-proficient metastatic colorectal cancer. PATIENTS AND METHODS: Patients received pembrolizumab 200 mg every 3 weeks plus binimetinib 30 mg twice daily alone (cohort A; previously treated with any chemotherapy) or with 5-fluorouracil, leucovorin, oxaliplatin (cohort C; previously untreated) or 5-fluorouracil, leucovorin, irinotecan (cohort E; previously treated with 1 line of therapy including fluoropyrimidine + oxaliplatin-based regimen) every 2 weeks. Binimetinib dose-escalation to 45 mg twice daily was planned in all cohorts using a modified toxicity probability interval design (target dose-limiting toxicity [DLT], 30%). The primary endpoint was safety; investigator-assessed objective response rate was secondary. RESULTS: In cohort A, 1/6 patients (17%) had DLTs with binimetinib 30 mg; none occurred in 14 patients with 45 mg. In cohort C, 3/9 patients (33%) had DLTs with binimetinib 30 mg; dose was not escalated to 45 mg. In cohort E, 1/5 patients (20%) had DLTs with binimetinib 30 mg; 5/10 patients (50%) had DLTs with 45 mg. Enrollment was stopped in cohort E binimetinib 45 mg and deescalated to 30 mg; 2/4 additional patients (50%) had DLTs with binimetinib 30 mg (total 3/9 [33%] had DLTs with binimetinib 30 mg). Objective response rate was 0% in cohort A, 9% in cohort C, and 15% in cohort E. CONCLUSION: Per DLT criteria, binimetinib + pembrolizumab (cohort A) was tolerable, binimetinib + pembrolizumab + 5-fluorouracil, leucovorin, oxaliplatin (cohort C) did not qualify for binimetinib dose escalation to 45 mg, and binimetinib + pembrolizumab + 5-fluorouracil, leucovorin, irinotecan (cohort E) required binimetinib dose reduction from 45 to 30 mg. No new safety findings were observed across cohorts. There was no apparent additive efficacy when binimetinib + pembrolizumab was added to chemotherapy. Data did not support continued enrollment in cohorts C and E.

NCI10066: a Phase 1/2 study of olaparib in combination with ramucirumab in previously treated metastatic gastric and gastroesophageal junction adenocarcinoma.

BACKGROUND: Our preclinical work revealed tumour hypoxia induces homologous recombination deficiency (HRD), increasing sensitivity to Poly (ADP-ribose) polymerase inhibitors. We aimed to induce tumour hypoxia with ramucirumab thereby sensitising tumours to olaparib. PATIENTS AND METHODS: This multi-institution single-arm Phase 1/2 trial enrolled patients with metastatic gastroesophageal adenocarcinoma refractory to ≥1 systemic treatment. In dose escalation, olaparib was evaluated at escalating dose levels with ramucirumab 8 mg/kg day 1 in 14-day cycles. The primary endpoint of Phase 1 was the recommended Phase 2 dose (RP2D), and in Phase 2 the primary endpoint was the overall response rate (ORR). RESULTS: Fifty-one patients received ramucirumab and olaparib. The RP2D was olaparib 300 mg twice daily with ramucirumab 8 mg/kg. In evaluable patients at the RP2D the ORR was 6/43 (14%) (95% CI 4.7-25.6). The median progression-free survival (PFS) was 2.8 months (95% CI 2.3-4.2) and median overall survival (OS) was 7.3 months (95% CI 5.7-13.0). Non-statistically significant improvements in PFS and OS were observed for patients with tumours with mutations in HRD genes. CONCLUSIONS: Olaparib and ramucirumab is well-tolerated with efficacy that exceeds historical controls with ramucirumab single agent for gastric cancer in a heavily pre-treated patient population.

Margin negative resection and pathologic downstaging with multiagent chemotherapy with or without radiotherapy in patients with localized pancreas cancer: A national cancer database analysis.

PURPOSE: Margin-negative (R0) resection is the only potentially curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC). Pre-operative multi-agent chemotherapy alone (MAC) or MAC followed by pre-operative radiotherapy (MAC + RT) may be used to improve resectability and potentially survival. However, the optimal pre-operative regimen is unknown. METHODS: Patients with non-metastatic PDAC from 2006 to 2016 who received pre-operative MAC or MAC + RT before oncologic resection were identified in the National Cancer Database. Univariable and multivariable (MVA) associates with R0 resection were identified with logistic regression, and survival was analyzed secondarily with the Kaplan Meier method and Cox regression analysis. RESULTS: 4,599 patients were identified (MAC: 3,109, MAC + RT: 1,490). Compared to those receiving MAC, patients receiving MAC + RT were more likely to have cT3-4 disease (76% vs 64%, p < 0.001) and cN + disease (33% vs 29%, p = 0.010), but were less likely to have ypT3-4 disease (59% vs 74%, p < 0.001) and ypN + disease (32% vs 55%, p < 0.001) and more likely to have a pathologic complete response (5% vs 2%, p < 0.001) and R0 resection (86% vs 80%, p < 0.001). On MVA, MAC + RT (OR 1.58, 95% CI 1.33-1.89, p < 0.001), evaluation at an academic center (OR 1.33, 95% CI 1.14-1.56, p < 0.001), and female sex (OR 1.43, 95% CI 1.23-1.67, p < 0.001) were associated with higher odds of R0 resection, while cT3-4 disease (OR 0.81, 95% CI 0.68-0.96, p = 0.013) was associated with lower odds of R0 resection. CONCLUSION: For patients with localized PDAC who receive pre-operative MAC, the addition of pre-operative RT was associated with improved rates of R0 resection and pathologic response.

A phase 1b expansion study of TAS-102 with oxaliplatin for refractory metastatic colorectal cancer.

BACKGROUND: TAS-102, a novel antimetabolite, is approved for treatment of refractory metastatic colorectal cancer (CRC). This study sought to determine whether the addition of TAS-102 to oxaliplatin (TAS-OX) was safe and effective in metastatic CRC previously treated with oxaliplatin. METHODS: This investigator-initiated, open-label, single-arm phase 1b study enrolled patients with metastatic CRC previously treated with 5-fluorouracil, irinotecan, and oxaliplatin. In dose escalation, TAS-102 was given at 3 dose levels: 25, 30, and 35 mg/m2 twice daily on day 1 to day 5 with 85 mg/m2 oxaliplatin on day 1 in 14-day cycles. The primary endpoint of dose escalation was the recommended dose for expansion, and in dose expansion, the primary endpoint was overall response rate (ORR) according to the Response Evaluation Criteria in Solid Tumors (RECIST, version 1.1). RESULTS: Forty-one patients were treated with TAS-OX. No dose-limiting toxicities were observed in the 11 patients treated in escalation. The recommended dose for expansion was 35 mg/m2 TAS-102 twice daily on day 1 to day 5 in combination with 85 mg/m2 oxaliplatin on day 1 in 14-day cycles. In the intention-to-treat population, the ORR was 2.4% (95% CI, 0%-12.9%) with 1 of 41 patients having a partial response, although 12 (29%) had tumor shrinkage. The median progression-free survival was 2.7 months (95% CI, 2.4-4.8 months) and median overall survival was 6.8 months (95% CI, 5.7-10 months). CONCLUSIONS: TAS-OX is safe with no unexpected toxicities at standard doses of each agent. The combination did not result in a clinically meaningful ORR, although progression-free survival and overall survival were encouraging in this heavily pretreated population. LAY SUMMARY: For metastatic colorectal cancer, the treatment combination of TAS-102 and oxaliplatin was found to be well-tolerated and revealed no unexpected side effects. Twelve of 41 patients had reductions in the size of their tumor, and the study treatment delayed the time to tumor growth as opposed to what would be expected.

A Single-Institution Experience of Induction 5-Fluorouracil, Leucovorin, Irinotecan, and Oxaliplatin Followed by Surgery Versus Consolidative Radiation for Borderline and Locally Advanced Unresectable Pancreatic Cancer.

OBJECTIVES: In the 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) era, the benefit of surgery versus definitive radiation for borderline resectable (BR) and locally advanced (LA) unresectable pancreatic ductal adenocarcinoma (PDAC) is not well defined. Our primary objective was to identify the survival impact of surgery for BR and LA unresectable PDAC treated with induction FOLFIRINOX. METHODS: We performed a single-center retrospective review of BR and LA PDAC treated with FOLFIRINOX from 2010 to 2018. The overall survival of surgery and consolidative radiotherapy was estimated in the Kaplan-Meier method and compared via the log-rank test. Subgroup analyses were conducted for BR and LA patients. RESULTS: We identified 101 BR and LA PDAC patients treated with induction FOLFIRINOX (41 surgeries and 60 consolidative radiotherapies). Surgery patients were 68.3% (28/41) BR and 31.7% (13/41) LA, whereas consolidative radiotherapy patients were 30% (18/60) BR and 70% (42/60) LA. The R0 resection rate was 100%, and 46.3% (19/41) received preoperative radiation. Median overall survival of surgery versus consolidative radiotherapy was 42.3 versus 19.6 months, respectively (P < 0.001). On multivariate analysis, surgery associated with improved survival. CONCLUSIONS: Surgery after induction FOLFIRINOX is feasible and has a clinically meaningful survival benefit in BR and LA PDAC.

Phase IB/II Randomized Study of FOLFIRINOX Plus Pegylated Recombinant Human Hyaluronidase Versus FOLFIRINOX Alone in Patients With Metastatic Pancreatic Adenocarcinoma: SWOG S1313.

PURPOSE: Pegylated recombinant human hyaluronidase (PEGPH20) degrades hyaluronan (HA) and, in combination with chemotherapy, prolongs survival in preclinical models. The activity of PEGPH20 with modified fluorouracil, leucovorin, irinotecan, and oxaliplatin (mFOLFIRINOX) was evaluated in patients with metastatic pancreatic cancer (mPC). MATERIALS AND METHODS: Patients had untreated mPC, a performance status of 0 to 1, and adequate organ function. Tumor HA status was not required for eligibility. After a phase Ib dose-finding study of mFOLFIRINOX plus PEGPH20, the phase II open-label study randomly assigned patients (1:1) to the combination arm or to mFOLFIRINOX alone (n = 138). The primary end point was overall survival (OS). RESULTS: PEGPH20 dosages of 3 µg/kg every 2 weeks were more tolerable than twice-weekly dosages used in the phase I study, so 3 µg/kg every 2 weeks was the phase II dosage. An amendment instituted enoxaparin prophylaxis in the PEGPH20 combination arm as a result of increased thromboembolic (TE) events. The planned interim futility analysis when 35 deaths (of 103 analyzable patients) occurred resulted in an OS hazard ratio (HR) of 2.07 that favored the control arm, and the study was closed to accrual. The treatment-related grade 3 to 4 toxicity was significantly increased in the PEGPH20 combination arm relative to control (odds ratio, 2.7; 95% CI, 1.1 to 7.1). The median OS in the mFOLFIRINOX arm was 14.4 months (95% CI, 10.1 to 15.7 months) versus 7.7 months (95% CI, 4.6 to 9.3 months) in the PEGPH20 combination arm. CONCLUSION: Addition of PEGPH20 to mFOLFIRINOX seems to be detrimental in patients unselected for tumor HA status. This combination caused increased toxicity (mostly GI and TE events) and resulted in decreased treatment duration compared with mFOLFIRINOX alone. The median OS in the mFOLFIRINOX control arm (14.4 months) is, to our knowledge, the longest yet reported and can be considered for patients with good PS.

Phase II Study of Modified FOLFOX6 With Bevacizumab in Metastatic Gastroesophageal Adenocarcinoma.

BACKGROUND: The median survival for patients with metastatic gastroesophageal adenocarcinoma is <12 months. Bevacizumab has demonstrated promising activity in metastatic gastroesophageal adenocarcinoma when used in combination with cisplatin-based regimens for patients from the Americas. We conducted a prospective phase II trial to investigate the efficacy of bevacizumab in combination with the oxaliplatin-based regimen, modified FOLFOX6, in patients with metastatic gastroesophageal adenocarcinoma. METHODS: Patients with untreated metastatic adenocarcinoma of the stomach, gastroesophageal junction, or distal esophagus received mFOLFOX6 (leucovorin 400 mg/m, fluorouracil 400 mg/m bolus and 2400 mg/m continuous infusion over 46 h, oxaliplatin 85 mg/m) and bevacizumab (10 mg/kg) every 2 weeks until disease progression or intolerance. Response by RECIST was evaluated by CT scan every 8 weeks. The primary objective was progression-free survival (PFS); secondary objectives were safety, response rate, and overall survival (OS). RESULTS: A total of 39 patients with untreated metastastic gastroesophageal adenocarcinoma were enrolled between September 2008 and June 2012. Median number of cycles administered was 12 (range, 4 to 86). The confirmed response rate was 56.4% (3 complete response and 19 partial response). The median PFS was 7.8 months and median OS was 14.7 months. Three patients remain on treatment, and 11 patients are alive, of whom 6 have survived >24 months. Treatment-related grade 3/4 toxicities included neutropenia (33.3%), neuropathy (20.5%), thromboembolism (VTE) (7.7%), thrombocytopenia (7.7%), anemia (2.6%), hypertension (2.6%), and proteinuria (2.6%). We observed no GI perforations or grade 3/4 GI hemorrhagic events. CONCLUSIONS: First-line mFOLFOX6 with bevacizumab for metastatic gastroesophageal adenocarcinoma was well tolerated and associated with longer PFS and OS compared with historical data from similar populations treated without bevacizumab. Our results suggest that the addition of bevacizumab to mFOLFOX6 may provide clinical benefit in American patients with metastatic gastroesophageal adenocarcinoma, a finding consistent with previous studies of first-line bevacizumab in combination with chemotherapy for this disease.

Final analysis of a phase II study of modified FOLFIRINOX in locally advanced and metastatic pancreatic cancer.

BACKGROUND: Modifications of FOLFIRINOX are widely used despite the absence of prospective data validating efficacy in metastatic disease (metastatic pancreatic cancer (MPC)) or locally advanced pancreatic cancer (LAPC). We conducted a multicentre phase II study of modified FOLFIRINOX in advanced pancreatic cancer to assess the impact of dose attenuation in MPC and efficacy in LAPC. METHODS: Patients with untreated MPC or LAPC received modified FOLFIRINOX (irinotecan and bolus 5-fluorouracil reduced by 25%). Adverse events (AEs) were compared with full-dose FOLFIRINOX. Response rate (RR), median progression-free survival (PFS) and median overall survival (OS) were determined. RESULTS: In total, 31 and 44 patients with LAPC and MPC were enrolled, respectively. In MPC, efficacy of modified FOLFIRINOX was comparable with FOLFIRINOX with RR 35.1%, OS 10.2 months (95% CI 7.65-14.32) and PFS 6.1 months (95% CI 5.19-8.31). In LAPC, efficacy was notable with RR 17.2%, resection rate 41.9%, PFS 17.8 months (95% CI 11.0-23.9) and OS 26.6 months (95% CI 16.7, NA). Neutropenia (P<0.0001), vomiting (P<0.001) and fatigue (P=0.01) were significantly decreased. [(18)F]-Fluorodeoxyglucose positron emission tomography imaging response did not correlate with PFS or OS. CONCLUSIONS: In this first prospective study of modified FOLFIRINOX in MPC and LAPC, we observed decreased AEs compared with historical control patients. In MPC, the efficacy appears comparable with FOLFIRINOX. In LAPC, PFS and OS were prolonged and support the continued use of FOLFIRINOX in this setting.