At a glance

What is histrelin?

Histrelin, known generically as histrelin acetate and sold under the brand Supprelin LA and formerly as Vantas, is a synthetic nine-amino-acid analog of gonadotropin-releasing hormone (GnRH, also called LHRH). It is one of the more potent GnRH agonists and is delivered from a flexible implant that sits under the skin and releases drug steadily for about 12 months, so a child or patient needs only one placement per year rather than repeated injections. Earlier forms of histrelin were given as daily injections; the modern products are implants.

How does histrelin work?

Histrelin binds the GnRH receptor on the pituitary. As with other agonists in its class, an initial dose briefly stimulates the gland, producing a short rise in luteinizing hormone and sex steroids, the flare. Because the implant then delivers the drug continuously, the receptors downregulate and desensitize, and gonadotropin output falls. Sex-hormone levels drop to prepubertal levels in children or castrate levels in men.

In central precocious puberty, that suppression stops the premature pubertal cascade, pausing bone maturation and breast or testicular development until a more appropriate age; in advanced prostate cancer, it removes the testosterone that hormone-sensitive tumors rely on. In the pivotal pediatric study, a single subdermal implant lowered peak stimulated luteinizing hormone from about 28 to under 1 mIU/mL and maintained¹ suppression of luteinizing hormone and sex steroids for a full year.

Is it FDA-approved?

Yes. Histrelin's U.S. approval and market history:

Supprelin LA is now the only histrelin implant sold in the U.S. Each implant is designed to deliver drug for about 12 months and is then removed and replaced.

What is histrelin prescribed for?

Histrelin is prescribed for central precocious puberty in children (Supprelin LA). It was also used as palliative treatment of advanced prostate cancer in adults (Vantas) until that implant was discontinued. The implant is placed and removed in a brief in-office procedure.

What are the side effects?

According to the Supprelin LA label², the most common side effect is a reaction at the implant site, reported in about half of children in clinical trials:

• Pain, bruising, soreness, or swelling where the implant is placed

More serious considerations include:

• Implant breakage or difficult removal
• A brief rise in sex hormones in the first week, which can temporarily worsen symptoms
• Mood and behavior changes such as irritability, crying, anger, or aggression
• Convulsions
• Raised pressure around the brain (pseudotumor cerebri), with symptoms such as headache and vision changes
• Severe skin reactions

More for sexual & reproductive