Using Combination Therapy as Treatment of Non-Clear Cell RCC

Bradley McGregor, MD, clinical director, Lank Center for Genitourinary Oncology, senior physician, Dana-Farber Cancer Institute, and instructor of medicine, Harvard Medical School, discusses a small study that evaluated the combination of atezolizumab (Tecqntriq) and bevacizumab (Avastin) for the treatment of patients with non-clear cell renal cell carcinoma (RCC).

As much as the treatment landscape has evolved for advanced RCC over the last several years, these efforts have been mainly focused on clear cell RCC, says McGregor. The majority of trials exclude patients with non-clear cell variant histology RCC, but retrospective data have shown these patients tend to do worse.

In an investigative response trial, McGregor says the combination of atezolizumab plus bevacizumab was evaluated in this patient population of 60 patients, 42 of which had variant histology RCC and 18 had clear cell RCC with sarcomatous differentiation.

About half of the patients with variant histology RCC had received prior systemic therapy, McGregor notes. The overall response rate in all patients was 33% and 26% independent of histologic type. McGregor says the patients with chromophobe had the lowest response rate, but the regimen was well-tolerated with minimal grade 3 or higher adverse events.