Relugolix

Relugolix Uses, Dosage, Side Effects, Food Interaction and all others data.

Relugolix is a gonadotropin-releasing hormone (GnRH) receptor antagonist used in the treatment of several hormone-responsive conditions. It was first approved in Japan in 2019, under the brand name Relumina, for the symptomatic treatment of uterine fibroids, and more recently by the United States' FDA in 2020, under the brand name Orgovyx, for the treatment of advanced prostate cancer. Relugolix has also been studied in the symptomatic treatment of endometriosis.

Relugolix is the first (and currently only) orally-administered GnRH receptor antagonist approved for the treatment of prostate cancer - similar therapies such as degarelix require subcutaneous administration - and therefore provides a less burdensome therapeutic option for patients who might otherwise require clinic visits for administration by healthcare professionals. In addition to its relative ease-of-use, relugolix was shown to be superior in the depression of testosterone levels when compared to leuprolide, another androgen deprivation therapy used in the treatment of prostate cancer. In May 2021, the FDA approved the combination product made up of relugolix, estradiol, and norethindrone under the market name Myfembree for the first once-daily treatment for the management of heavy menstrual bleeding associated with uterine fibroids in premenopausal women.

Approximately 56% of patients achieved castrate-level testosterone concentrations (9 Relugolix requires once-daily oral administration to maintain the desired testosterone concentrations.

Relugolix
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	Relugolix
Availability	Prescription only
Generic	Relugolix
Relugolix Other Names	Relugolix
Related Drugs	estradiol, Premarin, Xtandi, Casodex, Zytiga, Lynparza
Weight	120mg
Type	Oral tablet
Formula	C₂₉H₂₇F₂N₇O₅S
Weight	Average: 623.64 Monoisotopic: 623.176244497
Protein binding	Relugolix is 68-71% protein-bound in plasma, primarily to albumin and, to a lesser extent, α1-acid glycoprotein.
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country	United States
Last Updated:	September 19, 2023 at 7:00 am

Uses

Relugolix is an oral GnRH receptor antagonist for androgen deprivation therapy in the treatment of advanced prostate cancer.

Relugolix is indicated for the treatment of adult patients with advanced prostate cancer. In a combination product with estradiol and norethindrone, relugolix is indicated for the once-daily treatment for the management of heavy menstrual bleeding associated with uterine fibroids in premenopausal women.

Relugolix is also used to associated treatment for these conditions: Advanced Prostate Cancer, Heavy Menstrual Bleeding

How Relugolix works

The pathogenesis and progression of prostate cancer appear driven, at least in part, by the effects of testosterone. Androgen deprivation has been demonstrated to result in cell death and tumor regression in many well-differentiated prostate cancer cell lines - for this reason, androgen deprivation therapy (ADT) has become a standard in the treatment of prostate cancer, particularly in advanced disease.

Testosterone production in males is carried out in the Leydig cells of testes and is stimulated by luteinizing hormone (LH), which itself is produced in the pituitary gland following the binding of gonadotropin-releasing hormone (GnRH) to corresponding GnRH receptors. Relugolix is a competitive antagonist of these GnRH receptors, thereby decreasing the release of LH and, ultimately, testosterone.

Toxicity

Data regarding overdose of relugolix are unavailable.

Food Interaction

Take with or without food. Administration with food does not result in any clinically meaningful differences in pharmacokinetics.

Relugolix Drug Interaction

Moderate: famotidineMinor: enzalutamideUnknown: zolpidem, aspirin, alendronate, metoprolol, metoprolol, chlorhexidine topical, saw palmetto, pantoprazole, ubiquinone, bioflavonoids, cholecalciferol, alprazolam, rivaroxaban, abiraterone

Relugolix Disease Interaction

Major: osteoporosisModerate: QT prolongation

Elimination Route

The C_max and AUC of orally-administered relugolix increase proportionally following single doses - in contrast, with repeat dosing the AUC remains proportional to the dose while the C_max increases greater than proportionally to the dose. Following the administration of 120mg once daily, the steady-state AUC and C_max of relugolix were 407 (± 168) ng.hr/mL and 70 (± 65) ng/mL, respectively.

The absolute oral bioavailability of relugolix is approximately 12% and the median T_max following oral administration is 2.25 hours.

Half Life

The average effective half-life of relugolix is 25 hours, while the average terminal elimination half-life is 60.8 hours.

Clearance

The average renal clearance of relugolix is 8 L/h with a total clearance of 26.4 L/h.

Elimination Route

Approximately 81% of an orally administered dose was recovered in the feces, of which 4.2% was unchanged parent drug, while 4.1% of the dose was recovered in the urine, of which 2.2% remained unchanged.