Among patients with relapsed malignant mesothelioma, tremelimumab does not improve overall survival (OS) compared with placebo, according to a study published in The Lancet Oncology.1
There are no second-line therapies that show survival benefit for malignant mesothelioma.
For the double-blind DETERMINE trial (ClinicalTrials.gov Identifier: NCT01843374), researchers randomly assigned 569 patients with unresectable malignant mesothelioma 2:1 to receive intravenous (IV) tremelimumab 10 mg/kg or placebo every 4 weeks for 7 doses and then every 12 weeks until therapy discontinuation requirements were met. The primary study outcome was OS in the intent-to-treat (ITT) population.
Median OS was 7.7 months (95% CI, 6.8-8.9) in the tremelimumab arm vs 7.3 months (95% CI, 5.9-8.7) in the placebo arm (hazard ratio, 0.92; 95% CI, 0.76-1.12; P = .41).
At the time of data cutoff, 80% of patients in tremelimumab arm and 81% of patients in the placebo arm had died.
Sixty-five percent of patients in tremelimumab arm and 48% of patients in the placebo arm experienced grade 3 or greater treatment-emergent adverse events (AEs).
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The most frequently observed AEs in the tremelimumab arm were diarrhea, dyspnea, and colitis. The types and rates of incidence of AEs were consistent with those previously reported for CTLA-4 inhibitors.
- Maio M, Scherpereel A, Calabro L, et al. Tremelimumab as second-line or third-line treatment in relapsed malignant mesothelioma (DETERMINE): a multicenter, international, randomized, double-blind, placebo-controlled phase 2b trial. Lancet Oncol. 2017 July 17. doi: 10.1016/S1470-2045)17)30446-1 [Epub ahead of print]