According to subgroup analysis results from the phase 2 DELLphi-301 study, tarlatamab demonstrated durable efficacy with favorable benefit-risk profile among patients with previously treated small-cell lung cancer (SCLC), regardless of the presence of baseline brain metastases. 

These data were presented by Anne-Marie Dingemans, MD, PhD, Erasmus MC Cancer Institute, Rotterdam, Netherlands, at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.

As previously reported, “tarlatamab, a BiTE (bispecific T-cell engager) immunotherapy targeting delta-like ligand 3, demonstrated durable responses and promising survival outcomes in patients with previously treated SCLC,” stated Dr Dingemans. 

This analysis included 186 patients with relapsed or refractory SCLC with ≥2 lines of prior therapy with (n = 53) or without (n = 132) treated and stable brain metastases at baseline. Patients were randomized on a 1-to-1 basis to receive either 10 mg of tarlatamab or 100 mg of tarlatamab. The primary end point was objective response rate (ORR) based on presence of brain metastases in the overall population. Secondary end points included median progression-free survival (PFS), and overall survival (OS). 

At a follow-up of 13.6 months, ORR was 45.3% among patients with brain metastases and 32.6% among patients without brain metastases across both treatment arms. Median PFS was 5.6 months among patients with brain metastases and 3.9 months among patients without brain metastases. Median OS was not estimable. Grade ≥3 treatment-related adverse events occurred in 8 patients with brain metastases and 25 patients without brain metastases. Events that led to dose interruptions and/or reductions occurred among 3 patients with brain metastases and 11 patients without brain metastases. Events that led to treatment discontinuation occurred among 1 patient with brain metastases and 3 patients without brain metastases. No fatal events were observed. 

As Dr Dingemans concluded, tarlatamab “demonstrates a favorable benefit-risk profile in patients with previously treated small cell lung cancer irrespective of the presence of treated and stable brain metastases at baseline.” 

Source: 

Dingemans AMC, Ahn MJ, Blackhall FH, et al. DeLLphi-301: Tarlatamab phase 2 trial in small cell lung cancer (SCLC)—Efficacy and safety analyzed by presence of brain metastasis. Presented at the ASCO Annual Meeting. May 31-June 4, 2024; Chicago, IL. Abstract #8015