Multicenter phase 2 basket trial of durvalumab plus tremelimumab in patients with advanced rare cancer

Dual inhibition of CTLA-4 and PD-L1 has been shown to be an effective treatment strategy in many cancers. A multicenter phase 2 basket trial in Canada evaluated the combination of durvalumab plus tremelimumab in patients with rare cancer. Patients received four cycles of the combination followed by durvalumab until disease progression. Durable responses were noted in all cohorts except for osteosarcoma. The overall response rate for eligible patients was 16% (95% CI 10-23), with the best responses in the cohorts with salivary carcinoma (4/20; 20%; 6-44) and clear cell carcinoma of the ovary (8/39; 21%; 9-37). Grade 4 adverse events were observed in 2.8% of patients and grade 3 adverse events in 28.2%. The authors conclude that the combination of durvalumab and tremelimumab resulted in meaningful responses in salivary carcinoma and clear cell carcinoma of the ovary.