Oral Relugolix for Androgen-Deprivation Therapy in Advanced Prostate Cancer.

Injectable luteinizing hormone-releasing hormone agonists (e.g., leuprolide) are the standard agents for achieving androgen deprivation for prostate cancer despite the initial testosterone surge and delay in therapeutic effect. The efficacy and safety of relugolix, an oral gonadotropin-releasing hormone antagonist, as compared with those of leuprolide are not known.

In this phase 3 trial, we randomly assigned patients with advanced prostate cancer, in a 2:1 ratio, to receive relugolix (120 mg orally once daily) or leuprolide (injections every 3 months) for 48 weeks. The primary end point was sustained testosterone suppression to castrate levels (<50 ng per deciliter) through 48 weeks. Secondary end points included noninferiority with respect to the primary end point, castrate levels of testosterone on day 4, and profound castrate levels (<20 ng per deciliter) on day 15. Testosterone recovery was evaluated in a subgroup of patients.

A total of 622 patients received relugolix and 308 received leuprolide. Of men who received relugolix, 96.7% (95% confidence interval [CI], 94.9 to 97.9) maintained castration through 48 weeks, as compared with 88.8% (95% CI, 84.6 to 91.8) of men receiving leuprolide. The difference of 7.9 percentage points (95% CI, 4.1 to 11.8) showed noninferiority and superiority of relugolix (P<0.001 for superiority). All other key secondary end points showed superiority of relugolix over leuprolide (P<0.001). The percentage of patients with castrate levels of testosterone on day 4 was 56.0% with relugolix and 0% with leuprolide. In the subgroup of 184 patients followed for testosterone recovery, the mean testosterone levels 90 days after treatment discontinuation were 288.4 ng per deciliter in the relugolix group and 58.6 ng per deciliter in the leuprolide group. Among all the patients, the incidence of major adverse cardiovascular events was 2.9% in the relugolix group and 6.2% in the leuprolide group (hazard ratio, 0.46; 95% CI, 0.24 to 0.88).

In this trial involving men with advanced prostate cancer, relugolix achieved rapid, sustained suppression of testosterone levels that was superior to that with leuprolide, with a 54% lower risk of major adverse cardiovascular events. (Funded by Myovant Sciences; HERO ClinicalTrials.gov number, NCT03085095.).

The New England journal of medicine. 2020 May 29 [Epub]

Neal D Shore, Fred Saad, Michael S Cookson, Daniel J George, Daniel R Saltzstein, Ronald Tutrone, Hideyuki Akaza, Alberto Bossi, David F van Veenhuyzen, Bryan Selby, Xiaolin Fan, Vicky Kang, Jackie Walling, Bertrand Tombal, HERO Study Investigators

From the Carolina Urologic Research Center, Myrtle Beach, SC (N.D.S.); the University of Montreal Hospital Center, Montreal (F.S.); the Department of Urology, University of Oklahoma Health Sciences Center, Oklahoma City (M.S.C.); the Duke Cancer Institute Center for Prostate and Urologic Cancers, Duke University, Durham, NC (D.J.G.); Urology San Antonio, San Antonio, TX (D.R.S.); Chesapeake Urology, Towson, MD (R.T.); the Department of Strategic Investigation on Comprehensive Cancer Network, Interfaculty Initiative in Information Studies-Graduate School of Interdisciplinary Information Studies, University of Tokyo, Tokyo (H.A.); the Department of Radiation Oncology, Gustave Roussy Cancer Institute, Villejuif, France (A.B.); Myovant Sciences, Brisbane, CA (D.F.V., B.S., X.F., V.K., J.W.); and Service d'Urologie, Cliniques Universitaires Saint Luc, Brussels (B.T.).