Abstract 302P
Background
First-line treatment for ES-SCLC is immunotherapy combined with chemotherapy, yet prognosis remains poor. Combined targeting of PD-L1 and angiogenesis with chemotherapy may enhance anti-tumor immune responses vs standard of care.We present data from an ongoing phase II study of BNT327, an investigational bispecific antibody targeting PD-L1 and VEGF-A, plus chemotherapy in first-line ES-SCLC.
Methods
This open label, single arm, multicenter phase II study (NCT05844150) recruited pts aged ≥18 years with ECOG PS 0-1 with histologically or cytologically confirmed SCLC who had not received systemic treatment for ES-SCLC, to evaluate tumor responses per RECIST 1.1 and safety per CTCAE v5.0 of 30 mg/kg Q3W BNT327 plus platinum-etoposide administered Q3W for 4 cycles, followed by BNT327 Q3W until disease progression or unacceptable toxicity.
Results
As of 21 Nov 2023, 50 pts had been enrolled (median age 59 years, range 46–75, 80% ECOG 1). At the cutoff date 20 Dec 2024, 48 pts had completed ≥1 tumor evaluation, 5 pts remained on treatment. Median treatment exposure was 5.7 months (95% CI 4.4–7.2). After a median follow-up of 14.5 months (95% CI 13.4, 15.3), 42/48 pts had a best overall response of partial response. The overall objective response rate (ORR) was 87.5%; confirmed ORR was 85.4%. The disease control rate was 100%. Median progression free survival was 6.9 months (95% CI 4.3, 8.2); the median duration of response 5.5 months (95% CI 3.8, 6.8). Median overall survival (OS) had not yetmatured. The 12-month OS rate was 72.7%. All pts experienced ≥1 treatment-related adverse event (TRAE), while 43 pts (86%) had G≥3 TRAEs. The most commonly observed TRAEs were neutrophil count decrease (90%), anaemia (80%) white blood cell count decrease (76%), and platelet count decrease (62%). Immune-related AEs occurred in 42% of patients (21/50) and were G≥3 in 10% (5/50). No treatment-related deaths occurred. Three pts (6%) discontinued treatment due to TRAEs.
Conclusions
BNT327 plus platinum-based chemotherapy as a first-line treatment for ES-SCLC showed encouraging efficacy and an acceptable tolerability profile and is being assessed in a global phase III trial.
Clinical trial identification
NCT05844150.
Editorial acknowledgement
Scientific writing assistance was provided by Andrew Finlayson, an employee of BioNTech SE.
Legal entity responsible for the study
Biotheus Inc.
Funding
Biotheus Inc.
Disclosure
All authors have declared no conflicts of interest.