AstraZeneca and Merck & Co (MSD) have revealed positive results for their PARP inhibitor Lynparza in the early, adjuvant setting for certain breast cancer patients.
The phase 3 OlympiA trial is investigating Lynparza versus placebo in the adjuvant setting for patients with inherited (germline) BRCA-mutated (gBRCAm), high-risk HER2-negative early breast cancer.
Due to these positive results, the trial’s independent data monitoring committee (IDMC) has recommended halting the study early after Lynparza demonstrated efficacy in this patient population.
In an interim analysis, the trial was found to have crossed the superiority boundary for the primary endpoint of invasive disease-free survival (iDFS) associated with Lynparza treatment, compared to placebo.
Following the positive interim analysis results, the IDMC has recommended that the primary analysis should now take place.
The trial will also continue to assess key secondary endpoints, including overall survival and distant disease-free survival.
“Breast cancer remains one of the most common cancers globally and despite advances in treatment, many patients with high-risk disease will unfortunately develop a recurrence. We look forward to reviewing the results,” said José Baselga, executive vice president, oncology R&D at AZ.
Although AZ/Merck & Co did not disclose any plans for regulatory filings – at least not yet – an approval in the early, adjuvant setting for breast cancer could help to bolster Lynparza’s position in the PARP inhibitor category.
Lynparza is already approved for the treatment of gBRCAm, HER2-negative metastatic breast cancer patients.
An early breast cancer approval for Lynparza could also help to strengthen its position over rival PARP inhibitors – including Pfizer’s Talzenna which is also approved in the gBRCAm, her2-negative metastatic breast cancer setting.
“Analysis of the OlympiA trial, based upon the IDMC recommendation, could represent a potential step forward for patients with early-stage, high-risk primary breast cancer with a germline BRCA mutation,” said Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck & Co.
BRCA mutations are found in around 5% of all breast cancer patients, and around 55-65% of women with a BRCA1 mutation and approximately 45% with a BRCA2 mutations will develop breast cancer before they turn 70.