Dr Martín-Broto on the Efficacy of Sunitinib Plus Nivolumab in Clear Cell Sarcoma

Javier Martín Broto MD, PhD, medical oncologist, Fundación Jimenez Diaz University Hospital, Fundación Jiménez Díaz Institute for Medical Research; leader, Research Group ATBsarc, Villalba General Hospital, CITIUS III (Seville), discusses findings from the clear cell sarcoma subgroup of the phase 2 IMMUNOSARC II trial (NCT03277924) investigating treatment with sunitinib (Sutent) plus nivolumab (Opdivo). Notably, these results were shared at the 2024 ESMO Congress.

Patients between 12 and 80 years of age who presented with advanced, progressive, and measurable clear cell sarcoma were enrolled onto the trial following central pathology confirmation of their disease. Adult patients were treated with sunitinib at 37.5 mg per day during the first 2 weeks, and from then on, received the agent at 25 mg per day along with nivolumab at 240 mg every 2 weeks. Martín-Broto begins by saying that previous prospective trials in clear cell sarcoma primarily focused on MET inhibitors. This approach was based on a solid scientific rationale, making MET inhibition a logical therapeutic target for this specific sarcoma subtype, he says.

However, the outcomes of these trials were underwhelming, according to Martín-Broto. The median progression-free survival (PFS) in these studies ranged from approximately 2 to 4 months, the overall response rates (ORRs) werebetween 4% and 9%, and the median overall survival (OS) was less than 1 year, Broto reports. Despite the reasonable scientific background, the results were not particularly promising, and thus, these earlier trials with MET inhibitors did not offer significant clinical benefits for patients with clear cell sarcoma, he shares.

In contrast, the IMMUNOSARC II trial is showing encouraging results in efficacy-evaluable patients (n = 20). The primary end point of the investigation was the 6-month PFS rate, Martín-Broto continues. The outcome was notably positive, with a 6-month PFS rate of 51% (95% CI, 26%-75%), approximately double that observed in prior MET inhibitor trials, he emphasizes. Additionally, the median OS in IMMUNOSARC-II reached 17 months (95% CI, 8-26). The ORR showed further promise, with 17% of patients experiencing partial responses and 61% of patients achieving stable disease, Martín-Broto notes. These outcomes indicate a high clinical benefit rate with the regimen, with 36% (95%, CI 12%-61%) of patients remaining progression free at 1 year, he concludes.