Francesca Jackson-Spence, MRCP, on efficacy of savolitinib/durvalumab in papillary renal cancer

In this video, Francesca Jackson-Spence,MBChB, BSc, shares data from the study, “Final overall survival and new ctDNA analysis in MET-driven advanced papillary renal cancer (CALYPSO; NCT02819596),” which she presented at the 2025 American Society of Clinical Oncology Genitourinary Cancers Symposium in San Francisco, California. Jackson-Spence is a clinical research fellow in genitourinary oncology at Barts Cancer Institute, Queen Mary’s University in London.

Video Transcript:

What were the key efficacy findings from the CALYPSO trial?

Previously, some interim data from CALYPSO have been reported. We presented previously the confirmed response rate and the interim progression-free survival. That was presented by Cristina Suárez and published in the JCO.¹ Here at ASCO GU 25 we're presenting the updated PFS and overall survival data, and we're also presenting our ctDNA data.

Interestingly, the confirmed response rate in the intention to treat population was 32%, but this increases to 53% in the MET driven subset. The progression-free survival is 6.5 months in the intention to treat cohort, but increases to 13 months in that MET driven subset. For overall survival, we see the intention to treat cohort has an overall survival of around 18 months, which increases to 27.4 months in that MET cohort.

What were the key findings from the ctDNA analysis?

The ctDNA analysis from this study is really interesting. I want to focus on the ctDNA status at baseline; 48% of our patients were ctDNA positive at baseline. It potentially predicts response to treatment. If we look at the patients who responded to therapy with the savolitinib and durvalumab combination, 22% of the responders were ctDNA positive at baseline. In those non-responders, 89% of those were ctDNA positive at baseline. It also was predictive of overall survival. The patients who were ctDNA positive at baseline had poorer overall survival of 7.0 months vs 33 months in those who were ctDNA negative. We did also look at ctDNA clearance, and we showed that that was associated with better overall survival. However, our numbers were small. Only 2 patients cleared their ctDNA. So, whilst it's interesting, we have to await the results of the randomized phase 3 SAMETA study to validate those findings

This transcript was AI generated and edited by human editors for clarity

Reference

1. Suárez C, Larkin JMG, Patel P, et al. Phase II Study Investigating the Safety and Efficacy of Savolitinib and Durvalumab in Metastatic Papillary Renal Cancer (CALYPSO). J Clin Oncol. 2023;41(14):2493-2502. doi:10.1200/JCO.22.01414