Pharmaceutical giant AstraZeneca (AZ) has discontinued its cancer drug olaparib and scaled back plans for its depression drug TC-5214, at a total cost of $381.5 million, following clinical trial failures.
Phase II studies of olaparib have been halted after an interim analysis indicated that despite its known progression-free survival benefit, the drug did not confer an overall survival benefit in treatment of ovarian cancer.
The company has also had difficulty in finding a suitable tablet formulation for the drug.
TC-5214 has failed to reach its primary endpoint in two out of four phase III trials as a treatment for major depressive disorder:
• It failed to perform significantly better than placebo in patient measures on the Montgomery-Asberg Depression Rating Scale.
• It failed as an adjunct therapy to an antidepressant in patients who did not respond well to the antidepressant alone.
The two remaining phase III trials of TC-5214, together with a long-term safety study, will be continued. If they are successful, AZ will submit a new drug application to European regulators in 2015.
AZ has had to pay $285 million for terminating the olaparib trials and a $96.5m fee to continue the remaining TC-5214 trials. The latter payment will be doubled if the trials fail.