Abstract

Background: Budigalimab is a humanized, recombinant immunoglobulin G1 monoclonal antibody targeting programmed cell death protein 1 (PD-1). We present the safety, efficacy, pharmacokinetic (PK), and pharmacodynamic data from patients enrolled in the head and neck squamous cell carcinoma (HNSCC) and non-small cell lung cancer (NSCLC) expansion cohorts of the phase 1 first-in-human study of budigalimab monotherapy (NCT03000257; registered 15 December 2016).

Patients and methods: Patients with recurrent/metastatic HNSCC or locally advanced/metastatic NSCLC naive to PD-1/PD-1-ligand inhibitors were enrolled; patients were not selected on the basis of oncogene driver mutations or PD-L1 status. Budigalimab was administered at 250 mg intravenously Q2W or 500 mg intravenously Q4W until disease progression/unacceptable toxicity. The primary endpoints were safety and PK; the secondary endpoint was efficacy. Exploratory endpoints included biomarker assessments.

Results: In total, 81 patients were enrolled (HNSCC: N = 41 [PD-L1 positive: n = 19]; NSCLC: N = 40 [PD-L1 positive: n = 16]); median treatment duration was 72 days (range, 1-617) and 71 days (range, 1-490) for the HNSCC and NSCLC cohorts, respectively. The most frequent grade ≥ 3 treatment-emergent adverse event was anemia (HNSCC: n = 9, 22%; NSCLC: n = 5, 13%). Both dosing regimens had comparable drug exposure and increased interferon gamma-induced chemokines, monokine induced by gamma interferon, and interferon-gamma-inducible protein 10. Objective response rates were 13% (90% CI, 5.1-24.5) in the HNSCC cohort and 19% (90% CI, 9.2-32.6) in the NSCLC cohort. Median progression-free survival was 3.6 months (95% CI, 1.7-4.7) and 1.9 months (95% CI, 1.7-3.7) in the HNSCC and NSCLC cohorts.

Conclusions: The safety, efficacy and biomarker profiles of budigalimab are similar to other PD-1 inhibitors. Development of budigalimab in combination with novel anticancer agents is ongoing.

Abstract

Background: Agents targeting programmed cell death protein 1 (PD-1) have been approved as monotherapy for patients with small cell lung cancer (SCLC). In preclinical models, the combined targeting of PD-1 and delta-like protein 3 resulted in enhanced antitumor activity. Herein, we report results from the expansion arm of study NCT03000257 evaluating the combination of the anti-PD-1 antibody budigalimab and the targeted antibody-drug conjugate rovalpituzumab tesirine (Rova-T) in patients with previously treated SCLC.

Materials and methods: This expansion arm of a multicenter, open-label, multi-arm, first-in-human phase 1 clinical trial enrolled adult patients with progressive SCLC. The primary objective was to assess safety and tolerability. Patients received budigalimab 375 mg via intravenous infusion every 3 weeks, and Rova-T was administered as a dose of 0.3 mg/kg intravenously, on day 1 of the first and third 3-week cycle.

Results: As of October 2019, 31 patients with SCLC were enrolled and treated with budigalimab plus Rova-T. The combination was tolerated, with the most common treatment-emergent adverse events (in >30%) being pleural effusion, fatigue, and cough. The overall response rate was 24.1%, with one confirmed complete response and six confirmed partial responses. The overall response rate in patients with high delta-like protein 3 expression was similar (21.1%). The median progression-free survival was 3.48 months.

Conclusion: Combination therapy with budigalimab and Rova-T had promising efficacy and appeared to be tolerated in patients with SCLC. Although Rova-T development has been discontinued, development of budigalimab combined with other anticancer agents is ongoing.

Chronic human immunodeficiency virus type 1 (HIV-1) disease results in immune exhaustion and dampened T cell responses, and programmed cell death 1 (PD-1) inhibitors offer a potential approach to enable viral control without antiretroviral therapy (ART) through reversal of these effects. Budigalimab is an investigational humanized anti–PD-1 monoclonal antibody. Multiple intravenous (IV) low doses of budigalimab (Stage 1: 2 mg n = 10, 10 mg n = 10, placebo n = 5, two doses every 4 weeks; Stage 2: 10 mg n = 11, placebo n = 5, four doses every 2 weeks (Q2W)) were assessed in people living with HIV (PLWH; n = 41) in a randomized, double-blind, multicenter, placebo-controlled phase 1 study with an analytical treatment interruption (ATI) to identify an efficacious regimen with a favorable safety profile in PLWH. The primary endpoints were safety, tolerability and pharmacokinetics. Demographics and baseline characteristics were balanced across treatment groups, except for sex, which was mostly male. All participants identified as cisgender. Budigalimab was well tolerated for up to 44 weeks, with 29 of 41 participants experiencing an adverse event (AE), including 2 participants who each experienced one grade 1 reversible immune-related AE (thyroiditis, hyperthyroidism). Three grade 3 AEs were reported by two participants and one serious AE by one participant; none were deemed related to treatment. IV budigalimab 10 mg Q2W resulted in a slight accumulation of drug in serum, with concentrations remaining above the estimated concentration required for near-complete (>95%) PD-1 receptor saturation on CD8+ T cells for ~10 weeks in peripheral blood. In an exploratory efficacy analysis of a 12-week ATI initiated with the first of four 10 mg Q2W doses, 6 of 11 participants experienced a delayed rebound with a relatively low viral peak and/or off-ART viral control (<200 copies ml−1) for ≥6 weeks during ATI, with 2 sustaining ART-free viral control to study end (204−252 days). The study achieved prespecified endpoints, supporting further evaluation of budigalimab in PLWH in a phase 2 study.