Dingwei Ye, MD, PhD, discusses the initial efficacy and safety of BL-B01D1 in locally advanced or metastatic urothelial carcinoma. 

Dr Ye on Early Efficacy Data for BL-B01D1 in Metastatic Urothelial Carcinoma

Dingwei Ye, MD, PhD, director of the Multidisciplinary Team for Genitourinary Cancer, director, Fudan University Prostate Cancer Institute, China, discusses the initial efficacy and safety of the potential first-in-class EGFR/HER3-directed antibody-drug conjugate BL-B01D1 in locally advanced or metastatic urothelial carcinoma, as presented in a phase 1b/2 study (NCT05785039) during the 

This phase 1b/2 study investigated BL-B01D1 in patients with locally advanced or metastatic urothelial carcinoma who had progressed on standard therapies. The trial tested 3 dose levels (2.2, 2.5, and 2.75 mg/kg) administered every 3 weeks on days 1 and 8 of each cycle, Ye details. Patients continued treatment until progression or unacceptable toxicity.

Among the 27 patients evaluable for efficacy in the 2.2 mg/kg cohort, the confirmed overall response rate (ORR) was 33.3% (95% CI, 16.5%-54.0%), consisting of 11 partial responses (PRs), 9 of which were confirmed, and 15 patients achieving stable disease (SD), Ye reports. One patient was not evaluable. The disease control rate (DCR) reached 96.3% (95% CI, 81.0%-99.9%).

In the subset of 12 patients pretreated with 1 line of chemotherapy, the ORR was 75% (95% CI, 42.8%-94.5%), with 9 confirmed PRs and 3 achieving SD, Ye adds. The DCR for this group was 100% (95% CI, 73.5%-100%). Neither the median progression-free survival nor the median duration of response was reached with BL-B01D1 in either population.

Regarding safety, most adverse effects (AEs) were hematologic and manageable, Ye states. Common treatment-related AEs at the 2.2 mg/kg dose included anemia, leukopenia, thrombocytopenia, neutropenia, nausea, decreased appetite, hypoalbuminemia, vomiting, decreased lymphocyte count, alopecia, and stomatitis. Non-hematologic toxicities were mostly grade 1 or 2, and importantly, no cases of interstitial lung disease were observed. No new safety signals emerged during the study, Ye emphasizes.

These findings suggest that BL-B01D1 has manageable safety and encouraging antitumor activity, particularly in patients who have already been heavily pretreated, Ye concludes. Further evaluation of this promising agent in urothelial cancer is ongoing.

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Dr Ye on the Safety and Efficacy of BL-B01D1 in Locally Advanced/Metastatic Urothelial Carcinoma

Dingwei Ye, MD, PhD, professor, director, the Multidisciplinary Team for Genitourinary (GU) Cancer, director, Fudan University Prostate Cancer Institute; president, GU Cancer Committee of Chinese Anti-Cancer Association, discussesthe safety and efficacy outcomes of a phase 1b/2 study (NCT05785039) evaluating the potential first-in-class antibody-drug conjugate (ADC) BL-B01D1 in patients with locally advanced or metastatic urothelial carcinoma.

Ye begins by noting that this ADC is comprised of an EGFR x HER3 bispecific antibody attached to a novel topoisomerase I inhibitor payload.

Early results from the investigation of BL-B01D1 were presented at the 

. A total of 27 patients with locally advanced or metastatic urothelial carcinoma were enrolled onto the trial and were administered 2.2 mg of BL-B01D1 on days 1 and 8 of the trial, followed by once every 3 weeks thereafter.

The efficacy data were promising, Ye reports. The confirmed overall response rate (cORR) with BL- B01D1 was 33.3% (95% CI, 16.5%-54.0%) in the total population (n = 27). In patients who had receieved 1 prior line of chemotherapy (n = 12), the cORR was 75.0% (95% CI, 42.8%-94.5%), he adds. Additionally, the disease control rate (DCR) was 96.3% (95% CI, 81.0%-99.9%) in the total population and 100% (95% CI, 73.5%-100%) in those who had received priorchemotherapy.

The median duration of response (DOR) was not reached (NR; 95% CI, NR-NR) and the 6-month DOR was 100% (95% CI, 100%-100%) across both groups. Ye reports that the median progression-free survival (PFS) was not reached in either group; the 6-month PFS rate was 62.4% (95% CI, 62.4%, 32.2%-82.2%) in the total population and 100% (95% CI, 100%-100%) in the prior chemotherapy population.

No treatment-related deaths or interstitial lung disease events were reported, Ye continues, noting that the most common treatment-related adverse effects (TRAEs) were hematologic toxicities. Additionally, no new safety signals were observed with BL-B01D1, Ye concludes.

Dingwei Ye, MD, PhD, discusses the safety and efficacy outcomes of a clinical trial evaluating BL-B01D1 in locally advanced or metastatic urothelial carcinoma.

Dingwei Ye, MD, PhD

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Dr Ye on Early Efficacy Data for BL-B01D1 in Metastatic Urothelial Carcinoma

Dr Ye on the Safety and Efficacy of BL-B01D1 in Locally Advanced/Metastatic Urothelial Carcinoma