Experience with the once-yearly histrelin (GnRHa) subcutaneous implant in the treatment of central precocious puberty.

In 2007, a hydrogel histrelin implant was approved for the treatment of children with central precocious puberty (CPP). Children with CPP commonly have reduced height potential due to premature closure of the epiphyseal growth plates from exposure to sex steroids. Gonadotropin-releasing hormone analog (GnRHa) treatment halts puberty and allows for improvement of adult height. A hydrogel implant delivery system utilizing the potent GnRHa, histrelin, was first developed for use in men with prostate cancer. A once yearly histrelin subcutaneous implant was subsequently developed for the treatment of children with CPP. Studies to date have demonstrated safety, tolerability, and effectiveness of this treatment option in patients treated up to 2 years. The most common adverse effects of the implant relate to implant site pain or bruising. Cost of this treatment seems comparable to somewhat higher than the commonly used GnRHa treatment option, depot leuprolide. While long term studies are needed to establish continued efficacy and safety beyond 2 years of treatment, the histrelin implant appears to be an attractive option for GnRHa treatment in patients with CPP.