Myovant’s Prostate Cancer Drug Ready for FDA Filing

 

Myovant announced that its Phase III HERO trial relugolix met its primary endpoint and six key secondary endpoints in advanced prostate cancer. The company expects to use the data for a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) in the second quarter of 2020 and future submissions in Europe and Japan.

Myovant is one of the five Vant companies under Vivek Ramaswamy’s Roivant Sciences that was part of the $3 billion deal with Sumitomo Dainippon Pharma. Earlier this month, Roivant agreed to sell ownership of five its Vant companies to Sumitomo Dainippon Pharma.

Relugolix is a once-daily, oral gonadotropin-release hormone (GnRH) receptor antagonist that decreases testicular testosterone production. Testosterone is primarily responsible for stimulating prostate cancer.

In analysis of the responders, 96.7% of men receiving relugolix achieved sustained testosterone suppression to castrate levels. The company defined “responder” as achieving and maintaining testosterone suppression to less than or equal to 50 ng/dL from Week 5 through Week 48.

Five key secondary endpoints that were hit included superiority to leuprolide acetate, including rapid suppression of testosterone at days 4 and 15, profound suppression of testosterone at Day 15, rapid suppression of prostate-specific antigen (PSA) at Day 15, and suppression of follicle-stimulating hormone (FSH) at Week 24.

The drug also showed non-inferiority to leuprolide acetate on sustained testosterone suppression through 48 weeks.

“With the exciting results from the HERO study demonstrating the potential of relugolix to provide unique benefits compared to leuprolide, we look forward to submitting an NDA to the FDA,” said Lynn Seely, president and chief executive officer of Myovant Sciences. “We are now closer to our goal of bringing a precision oral medicine to the broad spectrum of men with advanced prostate cancer.”

The overall rate of adverse events in the relugolix and leuprolide acetate groups was comparable, 92.9% and 93.5%, respectively. The most common adverse events reported were hot flashes, fatigue, constipation, diarrhea and joint pain.

About 1,100 patients are expected to be enrolled in the study, including 430 men with metastatic prostate cancer to support analysis of a secondary endpoint of castration resistance-free survival. Data for that is expected in the third quarter of 2020. There are also 138 Chinese patients enrolled in China and Taiwan to support registration in China.

The trial was designed to study the safety and efficacy of relugolix in men with androgen-sensitive advanced prostate cancer who required at least one year of continuous androgen deprivation therapy. Patients enrolled were randomized 2:1 to receive a single loading dose of relugolix 360 mg followed by relugolix 120 mg once a day or treatment with leuprolide acetate 3-month depot injection.

Prostate cancer is the second most common form of cancer in men and the second leading cause of death from cancer in men in the U.S. About 3 million U.S. males are living with prostate cancer and about 170,000 will be newly diagnosed this year. The current standard of care are GnRH agonists, such as leuprolide acetate, or slow-release injections.