Introduction: Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate targeting DLL3, an atypical Notch ligand expressed in SCLC tumors. We evaluated the efficacy of Rova-T versus placebo as maintenance therapy in patients with extensive-stage-SCLC after platinum-based chemotherapy.Methods: MERU was a phase 3 randomized, doubleblinded, placebo-controlled study. Patients without disease progression after four cycles of platinum-based, front-line chemotherapy were randomized in a 1:1 ratio to receive 0.3 mg/kg Rova-T or placebo (every 6 wk, omitted every third cycle). Primary efficacy end points were progression-free survival (PFS) evaluated by the Central Radiographic Assessment Committee and overall survival (OS) in patients with DLL3-high tumors.Results: Median age of all randomized patients (N ¼ 748) was 64 years; 78% had TNM stage IV disease. At futility analysis of the subset with DLL3-high tumors, the hazard ratio for OS was 1.07 (95% confidence interval: 0.84-1.36) favoring the placebo arm, with median OS of 8.5 and 9.8 months in the Rova-T and placebo arms, respectively; futility criteria were met. Rova-T significantly improved PFS versus placebo by investigator assessment (4.0 versus 1.4 mo, hazard ratio ¼ 0.48, p < 0.001). Any-grade adverse events (!20%) in the Rova-T arm were pleural effusion (27%), decreased appetite (27%), peripheral edema (26%), photosensitivity reaction (25%), fatigue (25%), nausea (22%), and dyspnea (21%).Conclusions: Because of the lack of survival benefit in the Rova-T arm, the study did not meet its primary end point and was terminated early. As a result, the Central Radiographic Assessment Committee evaluation of PFS was not performed. The frequency of grade greater than or equal to 3 and drug-related toxicities were higher with Rova-T versus placebo. Rova-T was associated with unique toxicities, such as pleural and pericardial effusions, photosensitivity reaction, and peripheral edema, which should be carefully considered in the population with extensive-stage-SCLC.

Health regulatory approval of the 1.5 microg/kg body weight dose of pegylated interferon (PEG-I) alpha-2b in combination with ribavirin for the treatment of chronic hepatitis C was based on a study using PEG-I alpha-2b at doses of only 0.5 and 1.5 microg/kg body weight (BW), in spite of the previously shown flat dose-response curve at doses of > or =1.0 microg/kg. Our aim was to compare PEG-I alpha-2b 1.0 microg/kg with 1.5 microg/kg, both in combination with ribavirin. Open-label, randomized study in 227 patients with biopsy-proven chronic hepatitis C (Metavir < or =F2), receiving oral ribavirin (400 mg, twice daily) in combination with subcutaneous PEG-I alpha-2b (1.0 or 1.5 microg/kg, once weekly) for 24 weeks (genotype 2 or 3), or 48 weeks (other genotypes), followed by a 24-week drug-free period. Virologic response rates did not differ between the two doses of PEG-I alpha-2b: in patients infected with hepatitis C virus (HCV) genotype 1 or 4 treated with PEG-I 1.0 microg/kg BW, 38% (22/58) had a sustained virologic response compared with 39% (27/70) in the PEG-I 1.5 microg/kg BW dose group (P = ns). The corresponding values in patients infected with HCV genotype 2 or 3 were 71% (39/55) and 81% (29/36) respectively (P = ns). Adverse events led to transient or permanent dose reductions in fewer patients in the 1.0 microg/kg BW dose group (48/113 patients; 42%) than in the 1.5 microg/kg BW dose group (63/106 patients; 59%, P = 0.015). Furthermore, 89% of patients treated for 24 weeks but only 58% of patients treated for 48 weeks (P < 0.001) tolerated the treatment without relevant dose reduction or premature termination. In combination with ribavirin, PEG-I alpha-2b 1.0 microg/kg was as effective as 1.5 microg/kg but was better tolerated in patients with chronic hepatitis C and up to moderate fibrosis.

PurposeImmune checkpoint inhibition (ICI) therapy has improved patient outcomes in advanced non-small cell lung cancer (NSCLC), but better biomarkers are needed. A clinically validated, blood-based proteomic test, or host immune classifier (HIC), was assessed for its ability to predict ICI therapy outcomes in this real-world, prospectively designed, observational study.Materials and methodsThe prospectively designed, observational registry study INSIGHT (Clinical Effectiveness Assessment of VeriStrat® Testing and Validation of Immunotherapy Tests in NSCLC Subjects) (NCT03289780) includes 35 US sites having enrolled over 3570 NSCLC patients at any stage and line of therapy. After enrolment and prior to therapy initiation, all patients are tested and designated HIC-Hot (HIC-H) or HIC-Cold (HIC-C). A prespecified interim analysis was performed after 1-year follow-up with the first 2000 enrolled patients. We report the overall survival (OS) of patients with advanced stage (IIIB and IV) NSCLC treated in the first-line (ICI-containing therapies n=284; all first-line therapies n=877), by treatment type and in HIC-defined subgroups.ResultsOS for HIC-H patients was longer than OS for HIC-C patients across treatment regimens, including ICI. For patients treated with all ICI regimens, median OS was not reached (95% CI 15.4 to undefined months) for HIC-H (n=196) vs 5.0 months (95% CI 2.9 to 6.4) for HIC-C patients (n=88); HR=0.38 (95% CI 0.27 to 0.53), p<0.0001. For ICI monotherapy, OS was 16.8 vs 2.8 months (HR=0.36 (95% CI 0.22 to 0.58), p<0.0001) and for ICI with chemotherapy OS was unreached vs 6.4 months (HR=0.41 (95% CI 0.26 to 0.67), p=0.0003). HIC results were independent of programmed death ligand 1 (PD-L1). In a subgroup with PD-L1 ≥50% and performance status 0–1, HIC stratified survival significantly for ICI monotherapy but not ICI with chemotherapy.ConclusionBlood-based HIC proteomic testing provides clinically meaningful information for immunotherapy treatment decision in NSCLC independent of PD-L1. The data suggest that HIC-C patients should not be treated with ICI alone regardless of their PD-L1 expression.

764 Background: Inhibiting the transforming growth factor β (TGF-β) pathway, which plays a key role in tumor immunosuppression, may enhance the response to programmed death 1/programmed death ligand 1 (PD-1/PD-L1) monoclonal antibodies (mAbs). M7824 (MSB0011359C) is an innovative first-in-class bifunctional fusion protein composed of a mAb against PD-L1 fused with the extracellular domain of TGF-β receptor II, which serves as a TGF-β “trap.” We report results in patients (pts) with heavily pretreated colorectal cancer (CRC), an area of high unmet need since these pts no longer respond to standard therapies. Methods: In this expansion cohort of the ongoing, phase 1, open-label trial NCT02517398, pts with heavily pretreated (≥3rd line) advanced CRC receive M7824 1200 mg q2w until confirmed progressive disease (PD), unacceptable toxicity or trial withdrawal. The primary objective is best overall response (BOR) per RECIST v1.1; secondary objectives include safety/tolerability. Results: As of 28 June 2017, 32 heavily pretreated pts with advanced CRC (87.5% had ≥3 prior therapies) received M7824 for a median duration of 7.1 (range: 2-38) weeks; 2 pts remained on treatment. Among the 29 evaluable pts, 1 had a confirmed partial response (PR; ongoing at 8 months), 1 had stable disease (SD) and 27 had PD as BOR per independent read. The pt with a PR had CRC that was microsatellite stable (MSS), consensus molecular subtype (CMS) 4, KRAS mutant (mt) and PD-L1+; this pt had the highest tumor cell PD-L1 expression in our cohort (20%; PD-L1 expression was generally low among the other 24 pts with available results). 4 pts (12.5%) experienced 5 different grade 3 treatment-related adverse events (AEs; adrenal insufficiency, anemia, blood bilirubin increased, enteritis [leading to discontinuation] and fatigue); there were no grade ≥4 treatment-related AEs or treatment-related deaths. Conclusions: In heavily pretreated pts with advanced CRC, 1 pt (MSS, CMS 4, KRAS mt and PD-L1+) had a durable PR, 1 had SD and 27 had PD as BOR. M7824 showed a manageable safety profile. Updated data – including PD-L1, TGF-β and CMS results – will be presented. A study in pts with CMS 4 is in preparation. Clinical trial information: NCT02517398.