FDA Accepts GSK’s sNDA For Zejula As A First-Line Maintenance Treatment In Ovarian Cancer

GlaxoSmithKline’s Zejula could soon be used as a first-line maintenance treatment for certain types of ovarian cancer. On Monday, the U.S. Food and Drug Administration accepted the company’s submission of a supplemental New Drug Application for the new indication.

GSK is seeking approval of Zejula (niraparib) as a maintenance treatment in the first-line setting for women with advanced ovarian cancer who responded to platinum-based chemotherapy regardless of biomarker status. The FDA is reviewing the sNDA under the Real-Time Oncology Review (RTOR) pilot program, which could speed up the process for potential approval.

The sNDA was supported by data from the PRIMA study that demonstrated clinically-meaningful outcomes of niraparib treatment in the first-line maintenance setting. PRIMA was a double-blind, randomized Phase III study designed to evaluate Zejula versus placebo in first-line Stage III or IV ovarian cancer patients. The study included patients who responded to first-line treatment with platinum-based chemotherapy, including those at higher risk of disease progression, a population previously under-represented in first-line ovarian cancer studies, GSK noted. In that study, Zejula met its primary endpoint of a statistically significant improvement in progression-free survival for women regardless of their biomarker status. Treatment with Zejula resulted in a 38% reduction in the risk of disease progression or death in the overall study population when compared to placebo.

Zejula is an oral, once-daily PARP inhibitor used as maintenance treatment for ovarian cancer that secured approval from the FDA in 2017. PARP stands for poly ADP ribose polymerase, which is an enzyme many cancer cells are more dependent upon than regular, healthy cells are. PARP inhibitors are designed to disable DNA repair pathways in cancer cells, which make it difficult for those cells to survive. Zejula was the first PARP inhibitor to be approved by the FDA that does not require BRCA mutation or other biomarker testing. Zejula is currently approved in the U.S. as a maintenance treatment for women with recurrent ovarian cancer who are in response to platinum-based chemotherapy regardless of BRCA mutation status. It is also approved as a treatment for women with advanced ovarian cancer, following three or more chemotherapy regimens. The drug was the centerpiece of GSK’s 2018 $5.1 billion acquisition of Waltham. Mass.-based Tesaro Oncology.

Ovarian cancer is the fifth leading cause of cancer-related deaths in the United States. It is estimated that this year there will be more than 22,000 women in the U.S. diagnosed with the disease and about 14,000 disease-related deaths. While there are high response rates to platinum-based chemotherapy in the second-line advanced treatment setting, GSK noted that approximately 85% of patients will experience recurrence within two years. With each recurrence, the time a woman may spend without her cancer progressing until the next recurrence gets shorter, the company added.

PARP inhibitors are becoming more important in the treatment of some cancers. A study conducted by UT Southwestern has shown that PARP inhibitors could have broader effectiveness in treating other types of cancer, including ovarian and prostate cancer.-Bio Space