medwireNews: Combination treatment with nivolumab plus axitinib has achieved a high response rate in patients with metastatic renal cell carcinoma (RCC) enrolled in a phase 1/2 trial.
Presenting the findings at the 2022 ASCO Genitourinary Cancers Symposium in San Francisco, California, USA, Matthew Zibelman (Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA) noted that the trial was initiated before the results from various phase 3 studies of immune checkpoint inhibitor (ICI)–tyrosine kinase inhibitor (TKI) combinations were known.
And in response to an audience question about the role of nivolumab–axitinib given the wealth of ICI–TKI combinations available in this setting, the presenter admitted that it was unlikely to move to a phase 3 trial. But he stressed that the current results highlight that “axitinib is a good drug to pair with checkpoint inhibitors” due to its “easy titratability and short half-life.”
Zibelman reported on the treatment-naïve cohort of the phase 2 part of the trial, which included 43 patients aged a median of 65 years who had not received prior systemic therapy for metastatic RCC. A total of 41.9% of patients had favorable-risk disease as per the IMDC criteria, while 51.2% had intermediate-risk and just 6.9% had poor-risk disease.
Treatment with nivolumab 480 mg every 4 weeks plus axitinib 5 mg twice a day led to an objective response rate of 59.5%, with a complete response in one patient and partial responses in the remaining 24.
The rate of stable disease was 38.1%, giving a disease control rate of 97.6%. The presenter highlighted that just one of the 42 evaluable participants had progressive disease as the best response to treatment.
After a median follow-up of 11.5 months, the median progression-free survival duration was 16.4 months, with 60.8% of patients alive and progression-free at 12 months and 25.3% at 24 months. The median overall survival had not yet been reached at the time of analysis, and a respective 87.1% and 69.4% of patients were alive at the two timepoints.
The efficacy of nivolumab–axitinib was comparable to that of available approved ICI–TKI combinations in this setting, said Zibelman, adding that the safety profile was also similar.
Hypertension was the most common adverse event of grade 3 that was attributed to study treatment, observed at a rate of 41.5%, followed by diarrhea (9.8%), alanine aminotransferase elevation (7.3%), colitis (7.3%), and proteinuria (7.3%). There were no grade 4 or 5 events in this cohort.
A total of 20.5% of participants discontinued axitinib due to toxicity, while 18.2% discontinued nivolumab.
Zibelman concluded that “future follow-up will assess long-term outcomes in this cohort, as well as efficacy in the previously treated cohort, which includes patients who received either prior TKIs or prior [ipilimumab/nivolumab].”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2022 Springer Healthcare Ltd, part of the Springer Nature Group