On December 18, 2020, the U.S. Food and Drug Administration (FDA) approved relugolix (OrgovyxTM) as the first oral hormone therapy for use in adult patients with advanced prostate cancer.
Category/Class
Gonadotropin-releasing hormone (GnRH) receptor antagonist
Mechanism of Action
The drug binds to GnRH receptors, which reduces the release of luteinizing hormone, follicle-stimulating hormone, and testosterone.
Indication
Adults with advanced prostate cancer
Dosing
Given as an initial loading dose of 360 mg on the first day, then 120 mg daily
Administration
Tablets should be taken orally, with or without food, without chewing or crushing. If patients miss a dose by more than 12 hours, do not take the missed dose; resume with the next scheduled dose.
Adverse Reactions
More than 10%–15% of patients in clinical trials experienced hot flashes, fatigue, elevated glucose, elevated triglycerides, musculoskeletal pain, decreased hemoglobin, elevated liver enzymes, constipation, and diarrhea. Less than 10% of patients reported weight gain, insomnia, gynecomastia, hyperhidrosis, depression, and decreased libido.
Warnings
Increased risk of prolonged QT interval and embryo-fetal toxicity
Nursing Considerations
Relugolix can suppress the pituitary gonadal system; monitor laboratory testing during and after therapy. Monitor its therapeutic effect with periodic prostate-specific antigen testing. Because of the potential effect on QT/ATc interval, patients may require electrocardiogram and electrolyte monitoring. For treatment interruptions longer than seven days, resume relugolix with a loading dose of 360 mg on the first day, then 120 mg daily.
Drug-Drug and Drug-Food Interactions
Avoid using in combination with P-gp inhibitors and CYP3A inducers. P-gp inhibitors can increase its maximum concentration, whereas CYP3A inducers can decrease it.
Patient Education
Men with female partners of reproductive potential should use effective contraception during treatment and for two weeks after the last dose. Patients should be counseled about the potential for impaired fertility.
Gero-Oncology Considerations
No overall differences in safety or effectiveness were observed in clinical trials in patients aged 65 years and older compared to younger patients.
Patient Assistance
Call 833-674-6899 for a patient support program.