Histrelin: a long-acting GnRH implant
Clinical review pending
Histrelin suppresses sex hormone production. The implant is used for central precocious puberty and has also been used for prostate cancer.
What is histrelin?
Histrelin acetate is a synthetic GnRH analogue containing nine amino acids. It is sold as Supprelin LA and was previously sold as Vantas. Histrelin is among the more potent GnRH agonists. A flexible implant under the skin releases it steadily for about 12 months. This usually means one implantation per year instead of repeated injections. Earlier formulations were injected daily; today’s products are implants.
How does histrelin work?
Histrelin binds to GnRH receptors in the pituitary gland. Like other agonists in this class, it briefly stimulates the gland at first. Luteinizing hormone and sex hormones temporarily rise, an effect called a “flare.” With subsequent continuous release, the receptors become less sensitive and decrease in number. Gonadotropin release falls. Sex hormones drop to prepubertal levels in children and to castrate levels in men.
In central precocious puberty, this suppression slows pubertal development that has started too early. Bone maturation and breast or testicular development are held back until a more appropriate time. In advanced prostate cancer, hormone-sensitive tumor cells are deprived of testosterone. In the pivotal pediatric trial, a single implant lowered peak stimulated LH from about 28 to below 1 mIU/mL. Suppression of luteinizing hormone and sex hormones lasted a full year 1.
Is histrelin FDA-approved?
Yes. The table summarizes the US approval and market history described in the source article.
According to the source article, Supprelin LA is now the only histrelin implant marketed in the United States. It is designed to release the medicine for approximately 12 months, after which it is removed and replaced.
What is histrelin prescribed for?
Supprelin LA is used for central precocious puberty in children. Vantas was used for the palliative treatment of advanced prostate cancer in adults until sales of that implant were discontinued. Insertion and removal involve a short outpatient procedure.
What side effects are possible?
The prescribing information for Supprelin LA 2 identifies implantation-site reactions as the most common side effect. Around half of the children in clinical trials experienced them:
- Pain, bruising, tenderness or swelling at the implantation site
Other important risks include:
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Implant breakage or difficulty removing it
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A brief rise in sex hormones during the first week, which can temporarily worsen symptoms
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Mood and behavioral changes, such as irritability, crying, anger or aggression
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Seizures
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Increased pressure inside the skull, also called pseudotumor cerebri, potentially causing headaches and visual disturbances
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Severe skin reactions
Studies at a glance
| Date | Event |
|---|---|
| Early 1990s | Approval of an earlier histrelin formulation for daily injection |
| 2004 | Approval of the Vantas implant for advanced prostate cancer |
| 2007 | Approval of Supprelin LA for central precocious puberty [2] |
| 2021 | Manufacturer discontinuation of Vantas [3] |
References provided in the source article
Sources: FDA prescribing information for Supprelin LA; KFF Health News reporting on the discontinuation of Vantas; the pediatric implant trial (Eugster et al., Journal of Clinical Endocrinology and Metabolism, 2007, DOI: 10.1210/jc.2006-2479 1 ), indexed on PubMed.
Provenance and editorial review status
Adapted for Nutrient Desk from the source article. The claims and source attributions in the original text still require clinical review. This draft has not been cleared for indexing.