ASCO 2022 | Phase II study of neoadjuvant atezolizumab with gemcitabine and cisplatin in patients with MIBC

We conducted a single arm Phase II study of gemcitabine, cisplatin atezolizumab in patients with muscle invasive bladder cancer. It was a multicenter trial. Patients received gemcitabine and cisplatin with the ability to do split dosing, if they had renal dysfunction, along with atezolizumab. Patients received an additional dose of atezolizumab following chemotherapy and before surgery. The pathologic response rate was in the 60s percent range, and the pathologic complete response rate, so no disease, was about 40%.

These are somewhat higher than we might expect with gemcitabine and cisplatin chemotherapy alone. The event-free survival data, which we looked at at ASCO and reported, appears quite good in patients who had pathologic down-staging with essentially almost no patients experiencing relapses, if they experienced pathologic response, and of course, the higher the proportion of patients with pathologic response, the more patients are in that very good category and have outstanding outcomes. That adds to the totality of data we’ve seen with other chemo, immunotherapy neoadjuvant trials, leading to the possibility that we might see a different outcome with those studies compared to the metastatic trials with much more extensive advanced disease where chemo immunotherapy did not add to the benefit of chemotherapy alone.