Clinical and Immunologic Responses to a B-Cell Epitope Vaccine in Patients with HER2/neu-Overexpressing Advanced Gastric Cancer-Results from Phase Ib Trial IMU.ACS.001

PURPOSE

HER2/neu is overexpressed in up to 30% of gastroesophageal adenocarcinomas (GEA) and linked to poor prognosis. Recombinant mAbs to treat HER2/neu-overexpressing cancers are effective with limitations, including resistance and toxicity. Therefore, we developed a therapeutic B-cell epitope vaccine (IMU-131/HER-Vaxx) consisting of three fused B-cell epitopes from the HER2/neu extracellular domain coupled to CRM197 and adjuvanted with Montanide. This phase Ib study aimed to evaluate the optimal/safe dose leading to immunogenicity and clinical responses (https//clinicaltrials.gov/ct2/show/NCT02795988).

PATIENTS AND METHODS

A total of 14 patients with HER2/neu-overexpressing GEA were enrolled, and dose escalation (10, 30, 50 μg) was performed in three cohorts (C). Immunogenicity was evaluated by HER2-specific Abs and cellular responses, clinical responses by CT scans according to RECIST version 1.1.

RESULTS

IMU-131 was safe without vaccine-related significant local/systemic reactions or serious adverse events. A total of 11 of 14 patients were evaluable for changes in tumor size and vaccine-specific immune responses. One patient showed complete, 5 partial responses, and 4 stable diseases as their best response. HER2-specific IgG levels were dose dependent. In contrast to patients in C1 and C2, all patients in C3 mounted substantial HER2-specific Ab levels. In addition, cellular vaccine responses, such as Th1-biased cytokine ratios and reduced regulatory T cell numbers, were generated. Progression-free survival was prolonged in C3, correlating with the vaccine-specific humoral and cellular responses.

CONCLUSIONS

IMU-131 was well tolerated and safe. The induced HER2-specific Abs and cellular responses were dose dependent and correlated with clinical responses. The highest dose (50 μg) was recommended for further evaluation in a phase II trial, with chemotherapy + IMU-131 or chemotherapy alone, which is currently ongoing.

Abstract CT059: A Phase Ib open label multicenter study with a HER2/neu peptide vaccine administered with cisplatin and 5-fluorouracil or capecitabine chemotherapy shows safety, immunogenicity and clinical response in patients with HER2/Neu overexpressing advanced cancer of the stomach

Background: HER2/neu is overexpressed in 15-25% of gastric cancer patients and associated with poor prognosis. Alternative treatments to monoclonal antibodies are needed due to cost and global availability issues of mAbs. Thus a B-cell peptide vaccine (IMU-131) was developed, consisting of 3 fused B-cell epitopes (p467) from the HER2/neu extracellular domain coupled to CRM197 applied with the adjuvant Montanide. The current study evaluated the optimal and safe vaccine dose leading to immunogenicity and clinical responses.

Material & Methods: In an open-label multicenter Phase Ib trial in SE-Asia and Eastern Europe, 14 patients with HER2/neu overexpressing (++/+++) gastric or gastroesophageal junction adenocarcinoma were recruited to receive 3 injections of IMU-131 (days 0, 14, 35) in combination with chemotherapy (CT) every 21 days. Dose escalation with 10 µg, 30 µg and 50 µg was performed in 3 cohorts. Safety, immunogenicity and clinical responses were evaluated.

Results: No SAEs related to administration of IMU-131 were reported. Eleven of 14 patients were evaluable for vaccine-specific immune responses and 10 for tumor growth assessment. Higher p467- and Her-2 specific IgG levels were observed in cohort 2 (30 µg/dose) compared to cohort 1 (10 µg/dose). Two of five patients in cohort 2 showed minimal antibody titers. In contrast, all patients in cohort 3 (50µg/dose) responded to the vaccine with equally high antibody levels. Response rate was an exploratory endpoint and of 10 evaluable patients, 5 patients showed partial response and 4 patients showed stable disease. In cohort 3 the high antibody levels correlated with clinical response, while in cohort 2 only moderate correlations between humoral and clinical responses were observed. In cohort 1 partial response did not correlate with Ab levels, but rather with a high percentage of CD8 T-cells and increased inflammatory cytokine levels (high IFN-γ and TNF-α/IL-10 ratio).

Conclusions: The vaccine was well tolerated and safe with antibody responses at the highest dose (50 µg) showing a strong correlation with clinical responses. Thus, a dose of 50 µg was recommended for further evaluation in Phase II, featuring two arms of either IMU 131 plus CT or CT alone. We propose that this vaccine might be of significant medical benefit and further trials are warranted.

Citation Format: Ursula Wiedermann, Erika Garner-Spitzer, Yee Chao, Iurie Bulat, Arunee Dechaphunkul, Wichit Arpornwirat, Chaiyut Charoentum, Chia-Jui Yen, Thomas Cheung Yau, Marina Maglakelidze, Suebpong Tanasanvimon, Jedzada Maneechavakajorn, Aumkhae Sookprasert, Li-Yuan Bai, Wen-Chi Chou, Teerapat Ungtrakul, Christoph C. Zielinski, Leslie Chong, Nick Ede, Anthony J Good. A Phase Ib open label multicenter study with a HER2/neu peptide vaccine administered with cisplatin and 5-fluorouracil or capecitabine chemotherapy shows safety, immunogenicity and clinical response in patients with HER2/Neu overexpressing advanced cancer of the stomach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT059.

Efficacy and tolerability of sorafenib in unresectable/advanced hepatocellular carcinoma patients: Real-life experience in a Hong Kong tertiary liver cancer institute

382

Background: To evaluate the pattern and outcomes of sorafenib use in unresectable/advanced HCC in a real life setting in a tertiary Hong Kong liver cancer centre. Methods: A retrospective review of unresectable or advanced HCC patients treated with sorafenib at Queen Mary Hospital, Hong Kong from 2010-2015 was conducted. The objectives were to evaluate the sorafenib efficacy in overall treated population as well as different subgroups; and also reviewed the tolerability of sorafenib, especially its impact on liver function. Results: During the study period, 504 consecutive cases were identified and 493 cases with sufficient clinical data were analyzed. Consistent with Asia-Pacific etiologies, 79.3% patients had chronic hepatitis B. Sorafenib was mainly used in patients with high tumor burden (75.1% BCLC-C, 68.6% MVI or/and EHS). Two-third patients (68.2%) were pretreated, mostly with loco-regional therapies . While 70.2% patients had good baseline PS 0, one-quarter (26.6%) had Child-Pugh B/C cirrhosis state. The overall survival (OS) was 8.15 months, with no difference between HBV and non-HBV subgroups. Patients had Child-Pugh A(CP-A) had significantly better OS compared with those at CP-B/C (11.1m vs 3.29m vs 3.34m). About 36.1% patients received subsequent therapies. Safety profile was essentially consistent with literature with hand-foot-skin reaction (HFSR) being the most common AE (30.7% all-grade). Interestingly, the onset of HFSR was associated with significantly better OS (median: 14.59 vs 5.59 months, p <0.001). Notably, there was no significant change in the on-treatment levels of liver function in terms of bilirubin and plasma albumin level. Conclusions: Our study confirms the efficacy and safety in using sorafenib to treat unresectable or advanced HCC patients in the real life setting. Our results are s comparable with those reported in literature. In addition, we found that 1) similar efficacy in treating HCC regardless of HBV status, 2) positive association of OS with HFSR onset, and 3) no compromised liver function during sorafenib therapy.

Randomized phase II trial of sorafenib, capecitabine and oxaliplatin (SECOX) versus single agent sorafenib in patients with advanced hepatocellular carcinoma

365

Background: We aimed to compare the efficacy and tolerability of SECOX regimen with sorafenib alone as first-line treatment of advanced hepatocellular cancer (HCC) in a multicenter, open-label and randomized setting. Methods: Patients not suitable for surgery or various loco-regional therapies and no prior systemic therapy for advanced HCC were recruited in 3 centres. Eligible patients were randomly assigned to receive either SECOX (sorafenib 400 mg BD continuously, oxaliplatin 85 mg/m2 on D1, and capecitabine 1700 mg/m2 on D1-7 q2w) or sorafenib alone continuously in 1:1 ratio. Primary endpoint was time-to-progression (TTP). Secondary endpoints were tolerability, overall tumor response rate, overall survival (OS) and progression-free survival (PFS). Results: Forty-six patients were randomized and treated, of whom 22 were in the SECOX arm. Median age was 64 years and majority of the patients were male (72%). 40 patients (87%) were hepatitis B carrier, and 42 patients (91%) had Child-Pugh A liver function. Thirty patients (65%) had received prior non-systemic treatment for HCC. Median duration of follow-up was 7.8 months (mos) (range 0.3-25.8). At the time of analysis,one patient in the SECOX arm is still receiving treatment. Median TTP was 3.2 mos (95% CI 1.7-5.8) for SECOX vs 2.8 mos (95% CI 1.8-4.0) for sorafenib. The hazard ratio (HR) for TTP was 0.91 (95% CI 0.5-1.7; p=0.77; predetermined futility boundary HR ≥ 0.86). Median OS was 7.1 mos (95% CI 3.0-15.3) for SECOX vs 12.5 mos (95% CI 7.2-15.4) for sorafenib (p=0.29). Median PFS was 3.1 mos (95% CI 1.6-5.8) for SECOX vs 2.7 mos (95% CI 1.8-4.0) for sorafenib. 2 patients (9%) and no patients achieved partial response in the SECOX and sorafenib arms, respectively. The clinical benefit rate (CR+PR+SD) was 36% for the SECOX arm and 21% for the sorafenib arm (p=0.50). Incidence of treatment-related adverse events (trAEs) was common in both SECOX and sorafenib arms (64% and 71% respectively, p=0.75). The most common grade 3-4 trAE was ALP increase (14%) for SECOX and hand-foot skin reaction (25%) for sorafenib. Conclusions: The addition of capecitabine and oxaliplatin to sorafenib did not result in significant improvement in TTP. Clinical trial information: NCT02716766.

Outcomes of tyrosine kinase inhibitors (TKI) after immunotherapy in unresectable or advanced hepatocellular carcinoma (HCC) patients

361

Background: The outcomes of tyrosine kinase inhibitor(TKI) treatment after immune checkpoint inhibitors (PD-1i, PD-L1i, CTLA-4i) in unresectable/advanced HCC population is largely unknown. Methods: Retrospective analysis of advanced HCC patients treated with immune checkpoint inhibitors followed by TKI therapy at Queen Mary Hospital, Hong Kong were reviewed for the outcomes. Patients received locoregional therapy immediately after immunotherapy were excluded. Results: From January 2016 to July 2018, 30 HCC patients (83% of HBV, 80% of Child Pugh A, 83% of EHS/ MVI, median AFP=1,353ng/mL) who received TKI (11 lenvatinib, 10 sorafenib, 6 regorafenib, 3 axitinib) after immunotherapy were identified. TKI post-immunotherapy ("index TKI") was administered as third-line or beyond in 70% of patients. At the time of analysis (September 2018), median duration of index TKI was 72 days (IQR 36- 119∗) (∗3 patients were still receiving TKI). AFP declined in 53% of patients and the median change from baseline to nadir was -25% (IQR -65% to +6%). 40% of patients received subsequent systemic therapy. Median OS from index TKI was 602 days (95%CI 124-not reached; death event rate: 47%). 3 patients achieved partial response to TKI and they had at least stable disease with the previous immunotherapy. No unexpected safety issues of TKI and death related to adverse events were noted (table). Conclusions: TKI is active with good tolerabilty following immunotherapy in advanced HCC patients.[Table: see text]

Alpha fetoprotein (AFP) response and efficacy outcomes in the phase III CELESTIAL trial of cabozantinib (C) versus placebo (P) in advanced hepatocellular carcinoma (HCC)

423

Background: AFP response, defined as a decrease in serum levels of the tumor marker AFP after therapy, may be associated with improved survival of patients (pts) with HCC treated with locoregional or systemic therapy, and high baseline AFP levels may be associated with poor prognosis. In the phase III CELESTIAL trial (NCT01908426), C, an inhibitor of MET, VEGFR, and AXL, significantly improved overall survival (OS) and progression-free survival (PFS) versus P in pts with previously treated advanced HCC. Here we evaluate clinical outcomes with C in CELESTIAL based on AFP response or progression on treatment. Methods: 707 pts were randomized 2:1 to receive C (60 mg daily) or P. Eligible patients had a pathologic diagnosis of HCC, Child-Pugh score A, and ECOG PS ≤ 1. Pts received prior sorafenib and ≤ 2 lines of prior systemic therapy for HCC. Serum AFP levels were measured centrally at baseline and every 8 weeks thereafter. Outcomes were evaluated for pts with baseline AFP ≥ 20 ng/mL based on AFP response ( ≥ 20% decrease from baseline) or progression ( ≥ 20% increase from baseline) at Week 8. This definition of AFP response has been used in previous studies but requires further validation in large prospective studies. Results: Overall, 331 pts (70%) in the C arm and 160 (68%) in the P arm had baseline AFP ≥ 20 ng/mL; among these pts, 236 (71%) and 111 (69%), respectively, were evaluable for AFP response at week 8. Among evaluable pts, 117 pts (50%) in the C arm vs 14 (13%) in the P arm had an AFP response, and 72 (31%) vs 75 (68%) had AFP progression. Median OS with C was 16.1 mo for pts with an AFP response versus 9.1 mo for pts without a response (HR 0.61, 95% CI 0.45-0.84), and median PFS with C was 7.3 mo versus 4.0 mo (HR 0.55, 95% CI 0.41-0.74). For pts with AFP progression, median OS with C was 8.1 mo, and median PFS with C was 3.6 mo. Hazard ratios for OS and PFS with C also favored AFP responders over non-responders when analyzed using best response through week 24. Conclusions: The AFP response rate was higher with C versus P, and AFP response was associated with longer OS and PFS with C for pts with previously treated advanced HCC. On-treatment AFP changes warrant further evaluation as a biomarker of response. Clinical trial information: NCT01908426.

A phase Ib/II open label study of IMU-131 HER2/Neu peptide vaccine plus cisplatin and either 5-fluorouracil or capecitabine chemotherapy in patients with HER2/Neu overexpressing metastatic or advanced adenocarcinoma of the stomach or gastroesophageal junction

TPS176

Background: Gastric cancer is the 5th most frequently diagnosed cancer and the 3rd leading cause of cancer deaths. HER2/neu is overexpressed in 15% to 25% of patients with gastric cancer and associated with a poor prognosis. Monoclonal antibodies against HER2/neu have been shown to be effective but alternative treatments are needed due to cost and global availability issues. IMU-131 is a B-cell peptide vaccine composed of 3 B cell epitopes derived from the extracellular domain of HER2/neu. Polyclonal antibodies against IMU-131 peptides binding 3 separate regions (DIII, IV) of HER2/neu have been shown to elicit antitumor activity in vitro and a phase I study demonstrated safety and immunogenicity in Her-2 +/++ metastatic breast cancer patients. Fusion of the single peptides into a hybrid peptide conjugated to CRM197 in conjunction with the adjuvant Montanide (P467-CRM-Montanide) improved formulation and stability of the vaccine. With the present Phase 1b/2 trial performed in patients with HER2/neu overexpressing gastric or gastroesophageal junction (GEJ) adenocarcinoma, we hypothesized that administration of IMU-131 in addition to chemotherapy is safe and immunogenic, and will prolong survival and may delay tumor progression and/or reduce tumor burden. Methods: This study is an international open-label multicenter study performed in 16 Asian and Eastern European sites with a maximum of 18 patients enrolled in Phase 1b. This dose escalation study is designed to assess safety, tolerability, immunogenicity and recommended phase 2 dose (RP2D) of IMU-131. Each patient is administered three injections of IMU-131, at a single dose level on Days 0, 14, and 35, accompanied by chemotherapy cycles of cisplatin and 5-fluorouracil or capecitabine every 21 days. The RP2D will be evaluated in the dose expansion Phase 2 study with 68 patients being enrolled. Results: The study is ongoing with the completion of the phase 1b portion in 4Q18. Conclusions: No conclusions can be drawn at this time. Clinical trial information: NCT02795988.

Impact of antitumor activity on survival outcomes, and nonconventional benefit, with nivolumab (NIVO) in patients with advanced hepatocellular carcinoma (aHCC): Subanalyses of CheckMate-040

475

Background: NIVO (anti–PD-1 mAb) has demonstrated durable responses, long-term OS, and manageable safety in pts with aHCC in CheckMate-040 (El-Khoueiry, Sangro et al. 2017). With anti–PD-1 therapies, meaningful OS benefit may be seen even in pts who do not achieve a conventional response by RECIST v1.1. Here we report nonconventional benefit with NIVO and effect of antitumor activity on OS in sorafenib-experienced (sor-exp) pts with aHCC, including pts with a best overall response (BOR) of progressive disease (PD). Methods: Sor-exp pts received NIVO (3 mg/kg Q2W) in a phase 1/2 dose-expansion cohort regardless of PD-L1 status. Impact of antitumor activity on median OS (mOS) was determined by calculating change in target lesion size from baseline using quartile analyses (25% cutoff). Nonconventional benefit was analyzed by reductions or stabilizations in target lesion size after progression in pts with a BOR of PD. Results: Sor-exp pts (N=145) had a median follow-up of 14.9 mo. The ORR (RECIST v1.1) was 14% and the DCR was 56%. Median duration of stable disease (SD) was 4.3 mo and the DCR with SD ≥6 mo was 27%. Overall, mOS was 15.6 mo. Degree of OS benefit corresponded with antitumor activity in pts with decreases (≥25%, mOS not reached; 0–25%, mOS 17.7 mo) or increases (0–25%, mOS 11.7 mo; ≥25%, mOS 8.9 mo) in target lesion size (Table). In non-responders (n=124; including pts with BOR of SD or PD), mOS was 13.4 mo. Nonconventional benefit was observed in 11 of 56 pts (20%) with a BOR of PD. Updated clinical data with additional follow-up will be presented. Conclusions: In sor-exp pts, mOS with NIVO corresponded to degree of antitumor activity, with OS benefit not limited to RECIST v1.1 responders. Improved OS in non-responders is likely due to nonconventional benefit, supported by disease reduction or stabilization even in pts with a BOR of PD. Clinical trial information: NCT01658878. [Table: see text]

Nivolumab (nivo) in sorafenib (sor)-naive and -experienced pts with advanced hepatocellular carcinoma (HCC): CheckMate 040 study

4013

Background: Many pts with advanced HCC progress on SOC therapy. Nivo is a fully human anti–PD-1 IgG4 mAb that demonstrated durable responses (20% ORR with a median DOR of 9.9 mo; 9-mo OS rate was 74%) in pts with advanced HCC in the dose-expansion (EXP) phase of the CheckMate 040 study (NCT01658878; Melero et al. 2017). Here we present survival and durability of response data in both sor-naive and -experienced pts with advanced HCC in CheckMate 040. Methods: Pts naive to or previously treated with sor received nivo in phase 1/2 dose-escalation (ESC; 0.1–10 mg/kg) and -EXP (3 mg/kg) cohorts Q2W regardless of PD-L1 status. Primary endpoints were safety/tolerability (ESC) and ORR (EXP; ORR by investigator [INV] and blinded independent central review [BICR]) using RECIST v1.1. Secondary endpoints included DOR, DCR, and OS. Biomarkers were assessed using pre-treatment tumor samples. Results: Overall, pts (N=262) had a median follow-up of 12.9 mo, and 98% had Child-Pugh scores 5–6. In sor-naive pts (n=80), the ORR (INV) was 23%, with 44% of responses (8/18) ongoing (Table). The DCR was 63%; 40% of pts had stable disease ≥6 mo. In sor-experienced pts (n=182; 91% progressed on sor), the ORRs (INV) were 16%–19%. Overall, responses occurred regardless of etiology or tumor cell PD-L1 expression. Nivo had a manageable safety profile consistent with that reported in other tumor types. Updated data with additional 4 mo of follow-up will be presented. Conclusions: Nivo demonstrated durable responses with long-term survival and favorable safety in both sor-naive and -experienced pts with advanced HCC. Clinical trial information: NCT01658878. [Table: see text]

A phase II study of capecitabine, oxaliplatin and irinotecan (XELOXIRI) as salvage therapy in patients with refractory metastatic colorectal cancer

e15049

Background: Advanced colorectal cancer (CRC) refractory to oxaliplatin, irinotecan, and fluoropyrimidines is associated with poor prognosis. The triplet combination of 5-fluorouracil, oxaliplatin, and irinotecan has shown efficacy and tolerability in treatment-naive disease. We investigated the efficacy and tolerability of salvage capecitabine, oxaliplatin and irinotecan (Xeloxiri) in patients who progressed on standard chemotherapy. Methods: This prospective phase 2 study with a primary endpoint of overall response rate (ORR) recruited patients with advanced CRC that have progressed on standard chemotherapy containing fluoropyrimidines, oxaliplatin, and irinotecan either as monotherapy or doublets. Prior use of anti-VEGF, and anti-EGFR agents were allowed. Patients received capecitabine 1250mg/m2 twice daily on day 1-7, oxaliplatin 85mg/m2 and irinotecan 165mg/m2 on day 1 every 2 weeks until disease progression or intolerable toxicity. Secondary endpoints were progression free survival (PFS) and overall survival (OS). Results: Between July 2011 and May 2016, we recruited 32 patients. Median age was 57 and the median number of treatment cycles was 6. 16 patients (50%) were K-RAS wild-type (WT), of which 6 were also N-RAS WT. The ORR was 25% and the clinical benefit rate was 56%. 87.5% of patient received targeted therapy prior to study entry. 34% of patients had > 3 previous lines of therapy. Median PFS and OS were 5.0 months (95% CI 3.2 - 7.1) and 10.4 months (95% CI 7.2 - 11.4) respectively. K-RAS mutation status, number of lines of previous therapy, and site of primary tumour were not predictive of ORR, PFS or OS on univariate testing. Treatment-related adverse events (AEs) occurred in all patients, with the majority being hematological. Dose reductions occurred in 87.5% of patients. 59% required dose delays, and 56% received granulocyte-colony stimulating factor. Grade 3/4 AEs included neutropenia (34%), anemia (16%), thrombocytopenia (12.5%), febrile neutropenia (9%), diarrhea (6%), and anorexia (3%). Conclusions: Xeloxiri is efficacious and safe in patients with chemo-refractory CRC and is a promising treatment strategy as salvage. Clinical trial information: in progress.

Nivolumab dose escalation and expansion in patients with advanced hepatocellular carcinoma (HCC): The CheckMate 040 study

226

Background: HCC diagnosed at advanced stages has a poor prognosis. Patients who progress on sorafenib have few options. Nivolumab, a fully human IgG4 monoclonal antibody inhibitor of programmed death-1 (PD-1), has demonstrated clinical and survival benefit in a number of tumor types. Here we report updated interim analyses of safety, efficacy, and exploratory biomarkers in patients with advanced HCC treated with nivolumab in the CheckMate 040 study (NCT01658878). Methods: Patients enrolled had advanced HCC with or without hepatitis C or B virus (HCV or HBV) infection. Prior sorafenib was allowed. Phase 1 dose-escalation evaluated nivolumab (0.1–10 mg/kg) Q2W. Phase 2 dose-expansion was initiated in 4 cohorts: sorafenib naïve/intolerant, sorafenib progressors, HCV infected, and HBV infected. All cohorts received nivolumab 3 mg/kg Q2W. The primary endpoint in the dose-escalation phase was safety/tolerability, and the primary endpoint in the dose-expansion phase was objective response rate (ORR) by RECIST v1.1 (central review). Secondary endpoints included duration of response (DOR), disease control rate (DCR), and overall survival (OS). Biomarkers within pre-treatment tumors were assessed. Results: Across dose escalation and expansion phases, 262 patients have been treated. Grade 3/4 treatment-related adverse events occurred in 20%. No maximum tolerated dose was reached during dose escalation (n = 48). The ORR (investigator-assessed) was 20% (95% CI 15–26) in 214 patients treated in the dose expansion phase with a median DoR of 9.9 months; DCR was 64% (95% CI 58–71). Responses were observed across etiologies and regardless of tumor PD-L1 expression. ORRs of 23% (95% CI 13–36) and 21% (95% CI 11–34) were observed in the uninfected sorafenib-naive and -treated patients, respectively. The 9-month overall survival rate in the expansion phase was 74% (95% CI 67–79). Association between immune-cell biomarkers and clinical outcomes will be presented. Conclusions: In this heavily pretreated population, responses to nivolumab were durable with encouraging overall survival. Safety was manageable and consistent with that observed in other solid tumors with no new safety signals. Clinical trial information: NCT01658878.

Phase I/II safety and antitumor activity of nivolumab in patients with advanced hepatocellular carcinoma (HCC): CA209-040

LBA101

Background: Overexpression of PD-L1 in HCC has a poor prognosis. Safety and preliminary antitumor efficacy of nivolumab, a fully human IgG4 monoclonal antibody PD-1 inhibitor, was evaluated in a multiple ascending-dose, phase I/II study in patients (pts) with HCC. Methods: Pts with histologically confirmed advanced HCC with Child-Pugh (CP) score ≤ B7 and progressive disease (PD) on, intolerant of, or refusing sorafenib were enrolled. Dose escalation occurred in parallel cohorts based on etiology: no active hepatitis virus infection or virus-infected HCC pts. Pts received nivolumab 0.1 – 10 mg/kg intravenously for up to two years. The primary endpoint was safety. Secondary endpoints included antitumor activity using mRECIST criteria, pharmacokinetics, and immunogenicity. Results: The study has enrolled 41 pts with a CP score of 5 (n = 35) or 6 (n = 6), ECOG score of 0 (n = 26) or 1 (n = 15), 73% with extrahepatic metastasis and/or portal vein invasion, and 77% with prior sorafenib use. Eighteen pts remain on study, and 23 discontinued treatment due to PD (n = 17), complete response (CR; n = 2), drug-related adverse events (AEs; n = 2) and non-drug–related AEs (n = 2). Drug-related AEs of any grade occurred in 29 pts (71%; 17% grade 3/4), with ≥ 10% of pts experiencing aspartate aminotransferase (AST) increase and rash (each 17%), alanine aminotransferase(ALT) and lipase increase (each 15%), and amylase increase (12%). Grade 3 and 4 AEs ≥ 5% were AST increase (12%), ALT increase (10%) and lipase increase (5%). A dose-limiting toxicity occurred in an uninfected pt at 10 mg/kg; no maximum tolerated dose was defined in any cohort. Response was evaluable in 39 pts: 2 CR (5%) and 7 partial responses (PR; 18%). Response duration was 14–17+ months for CR, < 1–8+ months for PR, and 1.5–17+ months for stable disease (SD). Overall survival (OS) rate at 6 months is 72%. Conclusions: Nivolumab has a manageable AE profile and produced durable responses across all dose levels and HCC cohorts, with a favorable 6-month OS rate. Updated safety, antitumor activity, and biomarker data will be presented. Clinical trial information: NCT01658878. [Table: see text]

Effects of regorafenib therapy on health-related quality of life (HRQoL) in patients with metastatic colorectal cancer (mCRC) in the phase III CONCUR trial

697

Background: The CONCUR trial (NCT01584830) showed that the multikinase inhibitor regorafenib (REG) significantly improved overall survival and progression-free survival vsplacebo (PBO) in Asian patients with mCRC who had progressed on approved standard therapies. HRQoL was an exploratory endpoint. Methods: In this international multicenter trial conducted in Asia, patients were randomized 2:1 to receive REG 160 mg (n=136) or PBO (n=68) once daily for the first 3 weeks of each 4-week cycle. Prespecified QoL analyses were conducted on all 204 patients using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) and the EuroQol-five dimension questionnaire (EQ-5D). HRQoL outcomes were expressed as time-adjusted area under the curve (AUC) to allow descriptive evaluations of QoL in the REG and PBO groups across the entire treatment period. Individual domains were also compared using descriptive statistics. Results: Overall, changes in HRQoL were similar in the REG and PBO groups. Difference in least-squares (LS) mean time-adjusted AUC of the EORTC QLQ-C30 global health status/QoL (GH) score: −0.40 (95% CI: −3.53 to 2.72); differences in LS mean time-adjusted AUC for EQ-5D index and visual analog scale (VAS) scores: −0.03 (95% CI: −0.08 to 0.01) and −1.18 (95% CI: −4.01 to 1.66), respectively. The PBO group had <5 patients after cycle 3, so results should be interpreted with caution. Changes from baseline scores in cycles 2 and 3 did not appear to differ between REG and PBO on the 15 domains of the EORTC QLQ-C30, the EQ-5D index, and the VAS. Conclusions: No substantial differences in overall changes in HRQoL were seen between patients treated with REG and PBO in the CONCUR trial. Clinical trial information: NCT01584830. [Table: see text]

Final analysis of the phase 2 APEC study: Overall survival (OS) data and biomarker subanalyses for first-line FOLFOX or FOLFIRI with cetuximab (cet) once every 2 weeks in patients (pts) with KRAS or RAS (KRAS and NRAS, exons 2-4) wild-type (wt) metastatic colorectal cancer (mCRC)

566

Background: The Asia-Pacific, multicenter, nonrandomized, phase II APEC study previously reported that first-line therapy for pts with KRAS ex 2 wt mCRC consisting of C once every 2 weeks combined with FOLFOX or FOLFIRI achieved efficacy and safety profiles comparable to those reported in analogous pivotal studies involving weekly C. This final analysis presents OS data from the KRAS wt intent-to-treat (ITT) population, as well as subgroup efficacy analyses stratified by BRAF, PIKC3A, and all RAS mutation status. Methods: Eligible pts received C once every 2 weeks (day 1 of each cycle, 500 mg/m2) with FOLFOX or FOLFIRI (investigator’s choice). Study treatment continued until disease progression, dose-limiting toxicity or consent withdrawal. The primary endpoint was best confirmed overall response as assessed by RECIST 1.0; progression-free survival (PFS) and OS were secondary endpoints. In the evaluable populations, the status of BRAF, PIK3CA, and all RAS mutations was assessed retrospectively by pyrosequencing. Results: 42 months after the last patient was enrolled, median OS in the KRAS wt population was 26.8 months (Table). There were no unexpected safety findings. Additional biomarker results—including objective response rate (ORR), PFS, and OS subgroup analyses stratified on BRAF, PIKC3A, and all RAS mutation status—will be presented. Conclusions: The observed median OS of 26.8 months in the KRAS wt population is comparable to that reported in prior pivotal studies involving weekly C plus FOLFOX or FOLFIRI in the first line. These results suggest that C plus FOLFOX or FOLFIRI in a once-every-2-weeks regimen is active and tolerable as first-line therapy in this Asia-Pacific study population and a convenient alternative to weekly administration. Clinical trial information: NCT00778830. [Table: see text]

Next-generation sequencing: Profiling gallbladder cancer (GBC)

286

Background: Molecular profiling data of GBC is scant and it is often included with other biliary cancers for analysis, which may hinder advancing drug discovery. Methods: Archival formalin fixed paraffin embedded (FFPE) tissue of GBC from 2 research hospitals in Toronto (n=21) and Hong Kong (n=21) were analyzed by MassARRAY Sequenom panel (23 genes, 279 mutations), or by next general sequencing (NGS) using Proton or Illumina MiSeq TruSeq Amplicon Cancer Panel (48 genes, 212 amplicons, ≥500x coverage). Results of other biliary cancer and ampullary cancer from an ongoing profiling project were also reported. Results: Twelve biliary cancer samples first analyzed with Sequenom revealed no mutations. Reanalysis with NGS of these yielded mutations in 5. All subsequent samples were analyzed with NGS (n=57). Mutations were identified in 80% [53 mutations in 42 GBC, 8 mutations in 9 intrahepatic cholangiocarcinoma (IHC), 7 mutations in 6 hilar/distal bile duct cancers (DBD)]. The most frequent mutations in GBC were TP53 and SMAD4, and KRAS mutation was found in 7% (Table). PIK3CA mutation was found in 5% of GBC but not the other biliary cancers, and IDH1 mutation was exclusive for IHC, in agreement with published literature. TP53 mutations in GBC patients did not correlate with gender, tumor grade, survival, or treatment response to gemcitabine-based chemotherapy. There was no difference in mutation patterns in GBC between 2 institutions/countries. Conclusions: NGS can be utilized for molecular profiling of biliary cancer, detecting potentially actionable targets in the majority of cases. Our preliminary data suggests GBC may have its own molecular profile, deserving special consideration in trial design for biliary cancer. To our knowledge the current study is the biggest cohort of NGS analysis for GBC. [Table: see text]

Use of sorafenib in recurrent hepatocellular carcinoma (HCC) after liver transplantation

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Background: Sorafenib (Sor) is the only approved systemic therapy for advanced HCC yet the safety and efficacy for its use in patients (pts) who developed recurrence after liver transplantation (LT) has not been established. There is an unmet need for treatment option in this group of pts. Methods: This is a retrospective analysis of pts treated with Sor for recurrent HCC post-LT in Queen Mary Hospital, Hong Kong. Results: During year Jan 2008 to Feb 2014, 25 post-LT pts with HCC recurrence were treated with Sor. Tacrolimus and sirolimus were the immunosuppressant of choice during the same treatment period in 76% (19/25) and 40% (10/25) pts respectively. All pts had Child-Pugh A liver function and ECOG performance status 0-1. Majority of pts were chronic hepatitis B carriers (88%) and male (88%). Median time to recurrence was 13.2 months (range 3.4-71.1). Intrahepatic recurrence and extrahepatic recurrence were found in 52% and 80% of pts respectively. Up to 68% of pts received the standard dose of 800 mg/day. The most common adverse events (AEs) were hand-foot syndrome (44%) and diarrhea (28%). G3 transaminase elevation was found in 4 pts (16%), in which 2 had histological evidence of acute graft rejection. Both cases were associated with tailing down of tacrolimus upon tumor progression, and the liver function recovered after adjustment of immunosuppressant. Nine pts (36%) required dose adjustment. The median maintenance dose was 400 mg/day. The median duration of treatment was 4.44 months (95% CI 2.53-6.44). Median time to progression was 6.21 months (95% CI 2.83-9.63). Median overall survival was 13.6 months (95% CI 7.69-19.61). Ten (40%) pts also received other subsequent systemic therapy. Conclusions: Sor given in combination with tacrolimus and sirolimus did not lead to unexpected graft rejection. The drug is in general tolerated in this population and toxicities appeared to be similar to non-transplant pts. Further study is required to evaluate for drug interaction and efficacy.

A multicenter phase II study of sorafenib, capecitabine, and oxaliplatin (SECOX) in patients with advanced hepatocellular carcinoma: Final results of Hong Kong-Singapore Hepatocellular Carcinoma Research Collaborative Group study

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Background: This is a single arm, multi-center, phase II study to assess the efficacy and tolerability of sorafenib, oxaliplatin and capecitabine combination for the treatment of advanced hepatocellular carcinoma (HCC) patients. Methods: Eligible patients received SECOX regime—sorafenib 400 mg bid (Day one-fourteen), oxaliplatin 85 mg/m2 (Day one) and capecitabine 1700 mg/m2(Day one-seven) every two weeks. Response assessment was based on RECIST 1.0 criteria. The primary endpoint was time-to-progression (TTP) and the secondary endpoints were tumor response rate (RR), progression-free survival (PFS), overall survival (OS) and tolerability. Results: A total of 51 patients were enrolled in the trial.The median age was 58 years (range, 28-81) and 84% of patients were chronic hepatitis B carriers. Ninety percent of recruited patients belonged to BCLC stage C disease and 41 (80%) patients had extra-hepatic metastasis. The best RR was 16% and they were all partial response. Another 62% of patients achieved stable disease for at least eight weeks. The median TTP was 5.29 months (95% CI 3.81-5.88 months), PFS 5.26 months (95% CI 3.75-5.88 months) and OS was 11.73 months (95% CI 8.87- 15.38 months). Diarrhea (75%), Hand-foot-skin reaction (73%) and transient liver function derangement were the most commonly encountered adverse events, with the majority of patients having grade one or two. No treatment-related death was reported. Conclusions: The SECOX regime indicates preliminary promising activity and safety in Asian population with advanced HCC. Our data support a randomized trial comparing SECOX versus sorafenib alone for treatment of advanced HCC. Clinical trial information: NCT00752063.

Efficacy and safety of every-2-weeks cetuximab combined with FOLFOX or FOLFIRI as first-line therapy in patients with KRAS wild-type metastatic colorectal cancer (mCRC): An Asia-Pacific nonrandomized phase II study (APEC)

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Background: Randomized studies have shown that weekly cetuximab added to first-line FOLFOX or FOLFIRI improves clinical outcome in patients (pts) with KRAS wild-type (wt) mCRC. This Asia-Pacific multicenter study investigated FOLFOX or FOLFIRI + every 2 weeks cetuximab (C) as first-line therapy in pts with KRAS wt mCRC. Methods: Eligible pts received every 2 weeks cetuximab (d1 500 mg/m2 q14d) with, based on investigator’s choice, either FOLFOX (oxaliplatin 100 mg/m2, folinic acid [FA] 200 mg/m2 L-form or 400 mg/m2 racemic, then 5-fluorouracil [5-FU], as a 400 mg/m2 iv bolus and a 2400 mg/m2 infusion over 46 h) or FOLFIRI (irinotecan 180 mg/m2, FA 200 mg/m2 L-form, or 400 mg/m2 racemic, then 5-FU, as a 400 mg/m2 iv bolus and a 2400 mg/m2infusion over 46 h), until disease progression, unacceptable toxicity or consent withdrawal. Primary endpoint was tumor response; assessed radiologically (RECIST 1.0) every 8 weeks. Results: Data cut-off was 86 weeks after the date of last patient included. The ITT/safety population comprised 289 pts; 65.1% received FOLFOX + C and 34.9% FOLFIRI + C. Baseline characteristics were generally well balanced. Leukocyte count >10000/mm3was more frequent (16.5% vs 7.9%) and prior adjuvant treatment less frequent (21.3% vs 46.5%) in pts receiving FOLFOX + C. Response (CR or PR) was observed in 170 (58.8%) pts. The overall R0 resection rate was 10.0%. Survival data are not mature. Cetuximab dose intensity was >80% in 77.7% (FOLFOX + C) and 74.3% (FOLFIRI + C) of pts. Most frequent grade 3/4 adverse events (>10% in either arm) were neutropenia, diarrhea, hypokalemia, neuropathy (FOLFOX + C only) and skin reactions. Conclusions: Efficacy and safety profiles of every 2 weeks cetuximab combined with FOLFOX or FOLFIRI were similar to those reported for either chemotherapy plus weekly cetuximab in pivotal studies. Clinical trial information: NCT00778830. [Table: see text]

A phase I/II study of foretinib, an oral multikinase inhibitor targeting MET, RON, AXL, TIE-2, and VEGFR in advanced hepatocellular carcinoma (HCC)

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Background: Hepatocyte growth factor (HGF)/MET signalling plays a pivotal role in tumor cell proliferation, migration and invasion in HCC and circulating levels of HGF correlate with poor prognosis. This phase I/II trial (MET111645) evaluated foretinib, an oral multikinase inhibitor targeting MET, RON, AXL, TIE-2 and VEGFR, as first-line therapy in Asian advanced-HCC patients. Methods: Asian patients with measurable, unresectable/metastatic HCC, no prior sorafenib or other multi-kinase inhibitors, ECOG PS 0-1, adequate organ function and Child-Pugh grade A were recruited. The phase I was a standard 3+3 dose escalation design with a phase II cohort expansion. The primary endpoint was safety and tolerability at the maximum tolerated dose (MTD) and the secondary endpoints included antitumor activity (objective response rate [ORR], disease stabilization rate [DSR; confirmed CR/PR or SD for at least 12 weeks], and time to progression [TTP] evaluated by central review according to modified RECIST), and overall survival (OS) at the MTD, plus pharmacokinetics (PK). Results: Thirteen patients were enrolled in phase I. Two dose-limiting toxicities (DLT) (renal failure, proteinuria) were observed at 45 mg once daily (QD) but no DLTs were observed at 30 mg QD. Thus, the MTD was determined to be 30 mg QD. A further 32 patients were enrolled at the MTD, for a study total of 39 patients treated at 30 mg QD. The most common AEs, independent of causality,were hypertension (36%), decreased appetite (23%), and pyrexia (21%). The most common SAEs were hepatic encephalopathy (10%) and ascites (8%). Two patients discontinued foretinib due to AEs. No dose reductions were reported. Thirty-eight patients were evaluable for efficacy. The ORR was 24% (95% CI 11-40), DSR 79% (95% CI; 63-90), and the median TTP was 4.2 months (95% CI 2.7-7.5). Mature OS data will be presented. Mean steady-state exposures (AUC/Cmax) were comparable after administration of foretinib at 30 and 45 mg. Conclusions: Foretinib has an acceptable safety, tolerability, and PK profile in an Asian HCC population. It has demonstrated promising antitumor activity that warrants further testing in a randomized setting.