Dr Johnson on BL-B01D1 in Locally Advanced or Metastatic Solid Tumors

Melissa L. Johnson, MD, director, Lung Cancer Research, Sarah Cannon Research Institute; chair, Oncology Department, member, Medical Executive Committee, TriStar Centennial Medical Center, discusses findings from the phase 1 BL-B01D1-101 trial (NCT05194982) investigating the efficacy and safety of the EGFR- and HER3-directed antibody-drug conjugate (ADC) BL-B01D1 in patients with locally advanced or metastatic solid tumors, including non–small cell lung cancer (NSCLC).

BL-B01D1-101 enrolled 195 patients and had dose expansion and dose escalation parts. The recommended phase 2 dose was determined to be 2.5 mg/kg on days 1 and 8 every 3 weeks.

The dose expansion cohort of this trial enrolled 72 patients with EGFR wild-type NSCLC and 41 patients with EGFR-mutated NSCLC. At a median follow-up of 4.1 months, the overall response rate (ORR) was 63.2% and 44.9% in the EGFR-mutant and EGFR wild-type NSCLC cohorts, respectively. The disease control rate (DCR) was 89.5% in the EGFR-mutant NSCLC cohort and 91.8% in the EGFR wild-type NSCLC cohort.

This trial also evaluated BL-B01D1 in patients with small cell lung cancer (SCLC), nasopharyngeal carcinoma, and head and neck squamous cell carcinoma (HNSCC). Notably, patients with nasopharyngeal carcinoma experienced an ORR of 53.6% and a DCR of 100%. In the SCLC cohort, the ORR and DCR were 14.3% and 85.7%, respectively. In the HNSCC cohort, the ORR and DCR were 6.7% and 80%, respectively. Two patients with other solid tumors who were enrolled in the trial had a 0% ORR and a 100% DCR.

Regarding safety, 92% of patients experienced treatment-related adverse effects (TRAEs), 57% of patients experienced TRAEs of grade 3 or higher, and 29% of patients experienced treatment-related serious adverse effects. The most common TRAEs were leukopenia, anemia, neutropenia, and thrombocytopenia.

BL-B01D1 is a promising novel ADC for patients with solid tumors, and a future phase 3 trial with this agent will include patients with NSCLC, Johnson concludes.