First-line immunotherapy with durvalumab or the combination of durvalumab and tremelimumab does not improve survival in unselected patients with lung cancer, according to results from the MYSTIC trial.
The MYSTIC trial enrolled 1,118 patients with metastatic non-small cell lung cancer (NSCLC) who were randomly allocated to durvalumab alone, durvalumab plus tremelimumab, or chemotherapy.
The findings, presented at the ESMO Immuno-Oncology Congress last week, show that durvalumab alone or with tremelimumab did not improve overall survival (OS) or progression-free survival (PFS) compared to chemotherapy in patients with at least 25 per cent PD-L1 expression on tumour cells.
Median OS was 16.3 vs 12.9 months for durvalumab vs chemotherapy (HR 0.76; 97.54% CI 0.564-1.019; P=.036) and 11.9 vs 12.9 months for durvalumab plus tremelimumab vs chemotherapy (HR 0.85; 98.77% CI 0.611-1.173; P=.202). Median PFS was 3.9 vs 5.4 months for durvalumab plus tremelimumab vs chemotherapy (HR 1.05; 99.5% CI 0.722-1.534; P=.705). Almost 40 per cent of participants in the chemotherapy arm received subsequent immunotherapy after treatment discontinuation vs 6.1 and 3.1 per cent in the durvalumab and combination groups.
The authors point out that although statistical significance was not achieved for primary OS and PFS endpoints, first-line durvalumab demonstrated clinically meaningful improvement in OS compared to chemotherapy.