Tremelimumab Plus Cryoablation in Metastatic Renal Cell Carcinoma: A Pilot Study
Posted: Thursday, December 23, 2021
Patients with clear cell metastatic renal cell carcinoma showed a significant increase in immune cell infiltration within the tumor environment compared with those with non–clear cell histology when treated with cryoablation plus the monoclonal antibody tremelimumab. Padmanee Sharma, MD, PhD, of The University of Texas MD Anderson Cancer Center, and colleagues published their findings from this pilot study in Nature Communications.
“This study shows an increase in T-cell infiltration in the tumor microenvironment of [metastatic clear cell renal cell carcinoma] patients upon cryo-tremelimumab combination therapy and provides the rationale for future clinical trials focusing on [metastatic clear cell renal cell carcinoma] patients,” the authors concluded.
In this randomized pilot study, 18 patients with clear cell and 11 patients with non–clear cell metastatic renal cell carcinoma underwent treatment with either a combination of tremelimumab plus cryoablation (n = 15) or tremelimumab alone (n = 14). Many patients (68%) had no prior systemic treatment. The authors noted that five of the six patients who had undergone prior treatment with nivolumab were in the combination-therapy arm.
Median progression-free survival for patients with clear cell versus non–clear cell histology was 4.3 months and 3 months, respectively, with a hazard ratio of 0.5. The median overall survival was 33.7 months (95% CI = 16 months to not reached) for patients with clear cell histology and 16.2 months (95% CI = 7.8–33.7 months) for patients with non–clear cell histology. Few responses were observed in patients in both treatment arms, although three patients with clear cell histology in the combination-therapy arm had a durable response.
The primary endpoint of the study was safety, and immune-mediated toxicities with grade 3 or greater events occurred in 55% of patients, regardless of the type of treatment. Toxicities improved with immunosuppressants. The authors noted that capped dosing of tremelimumab may mediate these toxicities.
Disclosure: For a full list of authors’ disclosures, visit nature.com.