Phase Ib study of BI 836880 (VEGF/Ang2 nanobody) plus ezabenlimab (BI 754091; anti-PD-1 antibody) in patients (pts) with solid tumors

2579 Background: In preclinical studies, the combination of anti-VEGF/Ang2 and anti-PD-1 therapy has been shown to promote an immunopermissive state, which is supportive of T-cell-mediated tumor cell destruction. BI 836880 is a humanized bispecific nanobody that targets VEGF and Ang2, and ezabenlimab (BI 754091) is an anti-PD-1 antibody. Phase I studies investigating each as monotherapies have reported safety and preliminary antitumor activity. This ongoing Phase Ib study is evaluating the combination of BI 836880 and ezabenlimab in pts with advanced solid tumors. In Part 1 (dose escalation), the combination was feasible in pts with advanced NSCLC, with a recommended Phase II dose (RP2D) of BI 836880 720 mg + ezabenlimab 240 mg IV q3w. Here, we report updated results from Part 2 (expansion phase), which is assessing the antitumor activity and safety of the RP2D. Methods: Seven cohorts are currently recruiting pts in Part 2: metastatic (m) NSCLC after checkpoint inhibitor (CPI) monotherapy (Cohort A); mNSCLC after chemotherapy (CT) + CPI (Cohort B); mSCLC after CT ± CPI (Cohort C); 1st and 2nd recurrences of glioblastoma (GBM; Cohort D); immunotherapy-resistant m-melanoma (Cohort E); hepatocellular carcinoma (HCC) after prior sorafenib or lenvatinib ± CPI (Cohort F); and previously untreated/unresectable HCC (Cohort G). Primary endpoint is objective response rate (complete response + partial response [PR]). Results: As of January 2021, 196 pts have received BI 836880 plus ezabenlimab (14 in Part 1, 182 in Part 2 [Cohort A, 26; B, 30; C, 19; D, 31; E, 32; F, 28; G, 16]). 134 (68%) pts were male, median age was 63 years and 102 (52%) had prior CPI use. Any grade and ≥G3 adverse events (AEs; any cause) were reported by 160 (82%) and 62 (32%) pts, most commonly (all%/≥G3%) hypertension (20/8), asthenia (20/3), diarrhea, decreased appetite, and nausea (all 11/1). 95 (48%) pts had a drug-related AE, most commonly hypertension and asthenia (both 11%). 6 pts had a G4 AE (non-related: hyperkalemia + cardiac arrest, laryngospasm, gastrointestinal perforation; drug-related: anaphylactic reaction, acute pancreatitis, transaminases increased); 8 pts had a G5 AE (non-related: general physical health deterioration, epilepsy, hemoptysis, cardio-respiratory arrest, hepatic failure, intracranial hemorrhage, COVID-19 pneumonia; drug-related tracheal hemorrhage). 30 (15%) pts had immune-related AEs (3% ≥G3), including hypothyroidism (3%). 11 (6%) pts had an AE leading to discontinuation. Overall, 145 pts were evaluable for response: 9 pts achieved confirmed PR (2 pts in Part 1 and 7 in Part 2 [NSCLC, n = 3; SCLC, n = 1; GBM, n = 1; melanoma, n = 1; and 2nd-line HCC, n = 1]), 87 pts had stable disease and 49 pts had progressive disease. 111 pts remain on treatment. Conclusions: BI 836880 plus ezabenlimab had a manageable safety profile. The combination showed preliminary antitumor activity in a range of tumor types. Clinical trial information: NCT03468426.