Positive results for AZ, Merck & Co’s Lynparza in early breast cancer presented at ASCO

AstraZeneca (AZ) and Merck & Co’s PARP inhibitor Lynparza demonstrated positive results in BRCA-mutated high risk early breast cancer, according to new data presented at the 2021 American Society of Clinical Oncology (ASCO) annual meeting.

The new data from the phase 3 OlympiA trial showed Lynparza (olaparib) reduced the risk of invasive breast cancer recurrence, second cancers or death by 42% in the overall trial population, including patients who had completed local treatment and standard neoadjuvant or adjuvant chemotherapy.

At the three-year time point, 85.9% of patients treated with Lynparza remained alive and free of invasive breast cancer and second cancers versus 77.1% on placebo.

The PARP inhibitor also reduced the risk of distant disease recurrence or death by 43%, with fewer deaths occurring in patients receiving Lynparza at the time of the initial data cut-off.

However, the difference in overall survival (OS) did not reach statistical significance at the time of the interim analysis, although the study is set to continue to assess OS as a secondary endpoint.

In February, the OlympiA trial’s independent data monitoring committee (IDMC) recommended halting the study early after Lynparza demonstrated efficacy in this early breast cancer population.

“This is the first time that any medicine targeting a BRCA mutation has demonstrated the potential to change the course of early-stage breast cancer and offer hope for a cure,” said Dave Fredrickson, executive vice president, oncology business unit, AZ.

“By providing a treatment which significantly reduces the risk of breast cancer returning in these high-risk patients, we hope Lynparza will set a new benchmark demonstrating sustained clinical benefit. We are working with regulatory authorities to bring Lynparza to these patients as quickly as possible,” he added.

Lynparza became the first drug in the PARP inhibitor class to be approved in BRCA-positive breast cancer previously treated with chemotherapy in 2018.

Since then, the PARP inhibitor has chalked up additional approvals for the treatment of BRCA-mutated pancreatic cancer and for HRR gene-mutated and BRCA-mutated metastatic castration-resistant prostate cancer.

With AZ/Merck & Co already working with regulators to bring Lynparza to the market, a potential approval in the early, adjuvant setting for breast cancer would help to bolster the drug’s position in the PARP inhibitor category.