Non-clear cell renal cell carcinoma ( NccRCC ) and clear cell renal cell carcinoma with sarcomatoid differentiation ( sccRCC ) have historically been underrepresented in clinical trials.
Even with targeted therapy, most patients have inferior survival compared to clear cell renal cell carcinoma.
The combination of Atezolizumab ( Tecentriq ) and Bevacizumab ( Avastin ) has demonstrated safety and efficacy in clear cell renal cell carcinoma.
In this multicenter, phase II, open-label, single arm trial researchers have evaluated the efficacy of Atezolizumab and Bevacizumab in patients with nccRCC and sccRCC with more than 20% sarcomatoid differentiation.
Eligible patients had an ECOG performance status of 0-2 and may have received prior therapy. Prior PD-1/PD-L1 therapy was not allowed.
Patients underwent a mandatory baseline biopsy and subsequently received Atezolizumab 120 mg and Bevacizumab 15 mg/kg intravenously every 3 weeks.
Patients remained on therapy until radiographic progression, unacceptable adverse events, or withdrawal.
The primary end point was overall response rate ( ORR ) as determined by RECIST version 1.1.
65 patients were enrolled of whom 52 had greater than or to 1 response assessment and were included in this analysis.
36 patients had nccRCC ( papillary n=14, chromophobe n=8, unclassified RCC n=3, collecting duct n=3, translocation n=3, other n=5 ), and 16 patients had sccRCC.
17 patients received prior systemic therapy, 16 of whom had nccRCC.
The ORR was 31% in the overall cohort.
10 patients ( 19% ) developed grade 3 treatment-related adverse events, half of which were immune-related.
There were no grade 4-5 adverse events.
In this study, researchers have shown that therapy with Atezolizumab and Bevacizumab was safe and demonstrated anti-tumor activity in nccRCC and sccRCC. ( Xagena )
Source: Genitourinary Cancers Symposium, 2019