Dr. Moon on the Role of PARP Inhibitors in Prostate Cancer

Helen Heng-Shan Moon, MD, hematologist, oncologist, Kaiser Permanente Riverside Medical Center, discusses the role of PARP inhibitors in prostate cancer.

Patients with sensitizing mutations should be considered for treatment with PARP inhibitors, Moon says. However, a barrier still exists since not all patients with prostate cancer have access to or are offered testing for sensitizing mutations, Moon notes.

The phase 3 MAGNITUDE trial (NCT03748641) demonstrated the use of the PARP inhibitor niraparib (Zejula) in combination with abiraterone acetate (Zytiga) can improve progression-free survival for patients with metastatic castration-resistant prostate cancer (mCRPC) and homologous recombination repair (HRR) gene alterations, and these data have held up with follow-up, Moon continues. Notably, the phase 3 PROpel trial (NCT03732820) showed olaparib (Lynparza) plus abiraterone improved PFS, except the trial allowed patients with or without HRR gene alterations, Moon adds.

Data from PROpel raised the question if the prostate cancer field is ready to offer PARP inhibitors to patients without sensitizing mutations, Moon says. Olaparib is currently approved for patients with HRR gene-mutated mCRPC who progressed following prior treatment with enzalutamide (Xtandi) or abiraterone, and it will be interesting to see if it can be moved into an earlier treatment setting, Moon concludes.