On December 18, 2020, the Food and Drug Administration approved the first oral gonadotropin-releasing hormone (GnRH) receptor antagonist, relugolix, (ORGOVYX, Myovant Sciences, Inc.) for adult patients with advanced prostate cancer.

Efficacy was evaluated in HERO (NCT03085095), a randomised, open label trial in men requiring at least one year of androgen deprivation therapy with either prostate cancer recurrence following radiation or surgery or newly diagnosed castration-sensitive advanced prostate cancer.

Patients (N=934) were randomised (2:1) to receive relugolix 360 mg oral loading dose on the first day, followed by daily oral doses of 120 mg, or leuprolide acetate 22.5 mg injection subcutaneously every 3 months for 48 weeks.

The main efficacy outcome measure was medical castration rate defined as achieving and maintaining serum testosterone suppression to castrate levels (< 50 ng/dL) by day 29 through 48 weeks of treatment. The medical castration rate was 96.7% (95% CI: 94.9%, 97.9%) in the relugolix arm.

The most common adverse reactions (≥10%) in patients receiving relugolix in HERO were hot flush, musculoskeletal pain, fatigue, diarrhoea, and constipation.

The most common laboratory abnormalities (≥15%) were increased glucose, triglycerides, alanine aminotransferase, and aspartate aminotransferase.

Decreased haemoglobin was also observed.

The recommended relugolix dose is a loading dose of 360 mg on the first day followed by a daily oral dose of 120 mg at approximately the same time with or without food.

View full prescribing information here.

Source: FDA