March 28, 2017
(Last Updated: March 29, 2017 at 01:20pm PT)
By Alex Keown, BioSpace.com Breaking News Staff
WALTHAM, Mass – Shares of Tesaro are continuing to shoot up following the U.S. Food and Drug Administration’s approval of its ovarian cancer treatment, Zejula, formerly known as Niraparib, an oral, once-daily PARP inhibitor used as maintenance treatment.
Zejula is the first PARP inhibitor to be approved by the FDA that does not require BRCA mutation or other biomarker testing. The drug has been approved for the maintenance treatment of women with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy. Phase III trial data showed patients with the BRCA gene had 21 months of progression free survival – 15 months longer than the control group. Additionally, patients in the non-germline BRCA mutant cohort showed progression-free survival of 9.3 months, compared to 3.9 months for the control. Approximately two-thirds of study participants did not have germline BRCA mutations.
Tesaro said it anticipates launching Zejula in the United States by late April.
Mary Lynne Hedley, president and chief scientific officer at Tesaro, hailed the FDA for its rapid three-month approval of Zejula. As the company looks to have the drug ready for commercialization next month, Hedley said Tesaro is working with healthcare providers and insurance companies to ensure access to the treatment option.
Ursula Matulonis, director of Gynecologic Oncology at Dana-Farber Cancer Institute, said in a statement there have been “few treatment advances for women with recurrent ovarian cancer and even fewer options available for women who do not harbor BRCA mutations.”
“We are excited to have the opportunity to offer appropriate patients an oral, once-daily maintenance treatment that reduces the risk of cancer progression and extends the time between courses of chemotherapy for patients who have few treatment options,” Matulonis said.
Following Zejula’s rapid approval in the United States, Tesaro announced it was expanding its clinical development program of Niraparib for metastatic ovarian, breast and lung cancers.
The quick approval of Zejula steals the thunder from AstraZeneca , which released highly promising Phase III data regarding its own PARP inhibitor. Earlier this month, the London-based company said Lynparza delayed the recurrence of ovarian cancer by more than two years compared to placebo. In the latest Phase III study, Lynparza was used as a maintenance therapy in a trial of 295 patients with the BRCA mutation. The study demonstrated a “significant improvement in progression-free survival in germline BRCA-mutated (gBRCA), platinum-sensitive, relapsed ovarian cancer,” the company said in a statement. In a central-blinded sensitivity analysis of the drug versus placebo, patients taking Lynparza saw a progression-free survival rate of 30.2 months compared to 5.5 months for the placebo, the company said. Not only that, but AstraZeneca said the drug also achieved a statistically significant result in time to second progression or death.
While Tesaro is riding high right now, there are other companies delving the PARP inhibitor waters. Clovis Oncology saw the approval of to its PARP drug Rubraca in December 2016 for patients who have already gone through two chemotherapy treatments, but Clovis is looking to expand the use of the drug as a maintenance therapy. Pfizer is also looking to join in as well. When that company acquired Medivation last year, it also picked up an experimental PARP treatment.
