Real-world evaluation of the efficacy and safety of disitamab vedotin (RC48) in urothelial carcinoma.

BACKGROUND

Urothelial carcinoma (UC) is an aggressive malignancy with limited options for patients unresponsive to chemotherapy or immunotherapy. Disitamab vedotin (RC48), a HER2-targeted antibody-drug conjugate(ADC), has shown promising results in clinical trials, but real-world data are lacking.

METHODS

We conducted a single-center retrospective study of patients with histologically confirmed UC who received RC48 alone or in combination with PD-1 inhibitors between August 2022 and June 2024. Key inclusion criteria were at least one measurable lesion and adequate organ function; patients with incomplete records, concurrent active malignancies, or severe organ dysfunction precluding systemic therapy were excluded.

RESULTS

A total of 71 patients were included. The ORR was 69.0%, including 15 complete and 34 partial responses. The median PFS was 24 months, and OS data were immature at cutoff. In subgroup analyses, patients receiving RC48 + PD-1 inhibitors achieved an ORR of 70.0% versus 63.6% with RC48 monotherapy. Grade ≥ 3 treatment-related adverse events occurred in 21.1% of patients, most commonly anemia and decreased appetite; events were generally manageable with supportive care and dose modification.

CONCLUSIONS

RC48 showed encouraging activity and manageable safety in a real-world UC cohort. Prospective multicenter studies with longer follow-up are needed to validate these findings, compare monotherapy versus combination strategies, and define the optimal role of RC48 across UC disease stages.