AstraZeneca and biologics research arm MedImmune have reported that their cancer drug tremelimumab has failed to improve overall survival as a monotherapy in patients with mesothelioma.
The Phase IIb DETERMINE trial assessed the drug as a second or third-line treatment for unresectable malignant mesothelioma but failed to hit its primary target, dashing hopes of a new stand alone therapy for patients left with no approved options.
“We are disappointed that tremelimumab monotherapy did not demonstrate a survival benefit in this patient population with no approved medicines beyond first-line treatment,” said Robert Iannone, head of Immuno-Oncology, Global Medicines Development, at AZ, but he stressed that the firm remains confident in the drug’s clinical activity in combination with other agents.
Tremelimumab is being studied in combination with AZ’ anti-PD-L1 investigational immunotherapy durvalumab in multiple tumour types, including non-small cell lung cancer, squamous cell carcinoma of the head and neck, bladder, pancreatic, gastric and liver cancers.
The drug is designed to block the activity of CTLA-4 to “releases the brakes” on T cell activation and boost the immune response against cancer cells. AZ says preclinical data indicate that targeting both PD-L1 and CTLA-4 may have additive or synergistic effects, and thus together could offer a more powerful approach to fighting cancer.
A full evaluation of the final DETERMINE data will be submitted for presentation at an upcoming medical meeting this year, the firm noted.