Relugolix (Orgovyx) is an oral gonadotropin-releasing hormone receptor antagonist indicated for the treatment of advanced prostate cancer. As a novel endocrine therapy, it exhibits significant efficacy, but close attention to its side effects and precautions is required in clinical practice.
Side Effects of Relugolix (Orgovyx)
Metabolic Abnormalities
Increased blood glucose (44%), of which 2.9% are Grade 3-4.
Increased triglycerides (35%), of which 2% are Grade 3-4.
Musculoskeletal Pain
The incidence rate is 30%, including joint pain, back pain, limb pain, etc., with 1.1% being severe symptoms.
Hematological Indicators
Decreased hemoglobin (28%), with 0.5% requiring clinical intervention.
Hepatic Function Abnormalities
Increased alanine aminotransferase (27%), increased aspartate aminotransferase (18%).
Severe Side Effects of Relugolix (Orgovyx)
Risk of QT Interval Prolongation
Androgen deprivation therapy may prolong the QT/QTc interval, particularly in patients with concurrent congenital long QT syndrome, heart failure, electrolyte disorders, or those taking other QT-prolonging medications.
It is recommended to correct electrolyte disorders before medication and regularly monitor electrocardiograms (ECGs) and electrolyte levels.
Severe Hypersensitivity Reactions
Relugolix may induce hypersensitivity reactions such as angioedema and is contraindicated in patients with known severe hypersensitivity to relugolix or any of its components.
If symptoms such as laryngeal edema or dyspnea occur, discontinue the drug immediately and seek emergency medical attention.
Embryo-Fetal Toxicity
Animal studies have shown that relugolix can cause embryo death.
Male patients with female partners of childbearing potential should use effective contraceptive measures during treatment and for 2 weeks after the last dose.
Precautions for Relugolix (Orgovyx)
Dosage Adjustments and Administration Methods
Standard Regimen: A loading dose of 360 mg on the first day, followed by 120 mg orally once daily, which can be taken with or without food.
Missed Dose Management: If a dose is missed by less than 12 hours, take the missed dose immediately. Otherwise, skip the missed dose and take the next scheduled dose as planned.
Treatment Interruption: If treatment is interrupted for more than 7 days, restart with a loading dose of 360 mg.
Management of Drug Interactions
P-gp Inhibitors: Such as azithromycin and verapamil. Concomitant use should be avoided. If unavoidable, administer the medications with an interval of at least 6 hours and enhance monitoring for adverse reactions. For short-term use of P-gp inhibitors, relugolix may be suspended for up to 2 weeks.
P-gp and Strong CYP3A Inducers: Such as rifampicin. If concurrent use cannot be avoided, increase the relugolix dose to 240 mg daily.
Use in Special Populations
Elderly Patients: Patients aged 65 years and above account for 81% of users, but age has no significant impact on pharmacokinetics.
Hepatic or Renal Impairment: No dosage adjustment is required for patients with mild to moderate hepatic or renal impairment. However, data on patients with end-stage renal disease or severe hepatic impairment are lacking, so cautious assessment is necessary.
