The US Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation (BTD) to UK-Swedish drug maker AstraZeneca for its oral poly ADP-ribose polymerase (PARP) inhibitor Lynparza (olaparib) for treating a certain type of prostate cancer.

The BTD status means that the FDA will expedite a review of the data within 60 days of receipt.

The drug is specifically designed as a monotherapy treatment of BRCA 1/2 or ATM gene-mutated metastatic Castration Resistant Prostate Cancer (mCRPC) in patients who have received a prior taxane-based chemotherapy and at least one newer hormonal agent (abiraterone or enzalutamide).

The decision to grant BTD status is based on the results of a Phase III trial which showed that men suffering from prostate cancer with defective DNA damage repair mechanisms responded to Lynparza.

Antoine Yver, head of oncology, global medicines development at AstraZeneca, said more than 27,000 men died of prostate cancer last year in the US alone and there were currently very limited options for treating mCRPC. Once prostate cancer has progressed to mCRPC, treatment is focused on delaying the disease’s progression, improving symptoms and extending a patient’s lifespan.

Lynparza exploits tumor DNA repair pathway deficiencies to target and kill cancer cells. This mode of action gives olaparib the potential to treat a range of tumor types with DNA repair deficiencies. The drug has already been approved as a maintenance treatment of women with BRCA-mutated ovarian cancer.

AstraZeneca is investigating olaparib’s potential in other PARP dependent tumors. Phase III studies are underway in gastric and pancreatic cancers and adjuvant and metastatic BRCAm breast cancers. Further studies are planned.