During the American Society of Clinical Oncology ( ASCO ) Annual Meeting, the results of the phase III OlympiAD trial demonstrating for the first time that Olaparib ( Lynparza ) is superior to chemotherapy in patients with BRCA-related advanced breast cancer, were presented.

Although previous studies have suggested Olaparib could benefit patients with advanced breast cancers, researchers are now reporting that Olaparib improves profession-free survival better than standard chemotherapy.

PARP [ poly (ADP-ribose) polymerase ] is an enzyme used by healthy cells to repair themselves. However, cancer cells also use PARP to repair DNA damage, thus extending their growth and possible lethality.
Olaparib selectively binds to and inhibits PARP, preventing it from repairing DNA damage in cancer cells, particularly those cancer cells which have lost BRCA1 or BRCA2 function. This may help control the tumor or shrink it.

Although proportionally small ( only about 5% of breast cancer patients may have BRCA1/2 mutations ) researchers noted that these patient populations had a high likelihood of benefitting from Olaparib.

An earlier study resulted in the first FDA [ Food and Drug Administration ] approval of Olaparib in 2014 for patients with pretreated BRCA1/2 associated ovarian cancer. That study, a phase II trial published in the Journal of Clinical Oncology ( JCO ), showed Olaparib produced an overall tumor response rate of 26% in patients with advanced cancers associated with BRCA1 and BRCA2 mutations who had not previously responded to standard therapies.
For many of the patients in these trials, Olaparib was at least their third cancer therapy, illustrating the difficulty of treating cancers associated with these genetic mutations. ( Xagena )

Source: University of Pennsylvania School of Medicine, 2017