A newer treatment strategy for advanced urothelial cancer combines disitamab vedotin, a HER2-directed antibody-drug conjugate, with toripalimab, a PD-1 immune checkpoint inhibitor.
An antibody-drug conjugate, or ADC, acts as a targeted delivery system. The antibody component recognizes a protein expressed on cancer cells, while the attached cytotoxic drug is released after the ADC enters the tumor cell.
Disitamab vedotin targets HER2, which can be expressed in urothelial cancers of the bladder and urinary tract.
Toripalimab works differently. By blocking PD-1, it allows immune cells to remain active against cancer.
Together, the two treatments provide a dual strategy:
Targeted delivery of chemotherapy directly toward HER2-expressing cancer cells + immune activation through PD-1 blockade.
In a randomized phase III study involving patients with previously untreated HER2-expressing locally advanced or metastatic urothelial cancer, disitamab vedotin plus toripalimab produced significant improvements compared with conventional chemotherapy.
Median progression-free survival was 13.1 months versus 6.5 months, while median overall survival was 31.5 months versus 16.9 months. The objective response rate reached 76.1%, compared with 50.2% in the chemotherapy group.
Earlier phase Ib/II data had also demonstrated strong anti-tumor activity, with a confirmed response rate of approximately 73% and median overall survival exceeding 30 months in the study population.
Patients may be evaluated for this treatment when they have:
- Locally advanced or metastatic urothelial carcinoma
- Tumor tissue demonstrating HER2 expression
- Disease not suitable for curative local treatment
- Adequate organ function for systemic therapy
Potential adverse effects include peripheral neuropathy, liver-enzyme abnormalities, reduced blood-cell counts, fatigue and immune-related reactions.
This approach illustrates a major change in bladder and urothelial cancer treatment: instead of relying exclusively on platinum chemotherapy, doctors can combine highly targeted drug delivery with immune therapy to produce deeper and potentially longer-lasting tumor responses.
