AstraZeneca Presents Results From Interim Analysis Of Study 19 On Olaparib

(RTTNews) - AstraZeneca (AZN.L) presented results from a third interim analysis of Study 19 that suggest an improvement in overall survival or OS for patients with ovarian cancer treated with olaparib maintenance therapy following platinum-based chemotherapy. This was a secondary endpoint of the trial. These results support the previously reported benefits of olaparib in progression-free survival or PFS compared to placebo, the primary endpoint of the trial.

A 27% reduction in risk of death compared to placebo was seen in the overall trial population (HR 0·73 95% CI 0·55-0·96, nominal p=0.02483; median OS 29·8 vs 27·8 months), with the greatest reduction in the risk of death of 38% compared to placebo observed in patients with BRCA1/2 mutations (BRCAm) (HR 0·62, 95% CI 0·41-0·94, nominal p=0.02480; 34·9 vs 30·2 months). As this was the third analysis of survival, the nominal p-values did not meet the criterion for statistical significance and therefore the treatment effect observed for OS can only be considered descriptive. A number of patients continue to benefit from olaparib maintenance therapy, with 15% of BRCAm patients receiving olaparib for over five years.

The update from Study 19, presented today at the American Society of Clinical Oncology (ASCO) congress in Chicago, is based on a 77% data maturity conducted after more than five years total follow-up, with an additional three years of follow-up since the previous analysis. Two interim analyses of OS from Study 19 have previously been conducted, at 38% data maturity (HR 0·94, 95% CI 0·63-1·39, p=0·75) and 58% data maturity (HR 0·88, 95% CI 0·64-1·21, p=0·44) in the overall trial population.