My question is surrounding the duration of maintenance avelumab for metastatic urothelial carcinoma. My patient is a 70yo M presented with de novo metastatic urothelial carcinoma to lymph nodes and liver, treated front line with cisplatin/gemcitabine with significant partial response, now he has been on maintenance avelumab for a year. He has some new arthralgias that seem to improve with steroid courses, but otherwise is tolerating the avelumab. He has some small persistent disease on imaging. How long do you continue maintenance avelumab for? What would be your choice of second line therapy when he progresses on this?
Duration of maintenance avelumab has not been defined. The JAVELIN Bladder 100 trial continued maintenance Avelumab until confirmed disease progression, patient refusal, patient lost to follow-up, unacceptable toxicity, or study termination by sponsor, whichever comes first. However, many other anti-PD-1/anti-PD-L1 trials discontinue treatment at completion of 2 years of therapy. So that would be a reasonable timepoint. With small persistent disease on imaging and relatively good tolerability, I would favor continuing treatment in this patient and reassess at 2 years. Enfortumab vedotin would be a good next-line therapy option when he progresses on maintenance Avelumab, assuming he does not have significant peripheral neuropathy from prior chemotherapy or poorly controlled diabetes. I would also advocate for molecular testing to evaluate for FGFR alterations that could be targeted with an FGFR inhibitor.
