HISTRELIN - A REVIEW OF ITS PHARMACOLOGICAL PROPERTIES AND THERAPEUTIC ROLE IN CENTRAL PRECOCIOUS PUBERTY

Histrelin is a synthetic gonadotrophin-releasing hormone (GnRH) agonis t which, when administered over a prolonged period, suppresses the rel ease of gonadotrophins.from the anterior pituitary. Data from clinical trials undertaken in small numbers of patients with idiopathic centra l precocious puberty have demonstrated that histrelin 8 to 10 mug/kg/d ay administered subcutaneously desensitises the anterior pituitary to gonadotrophin secretion within 3 months, ablating the pubertal gonadot rophin response to GnRH stimulation and reducing circulating gonadal s ex steroid levels. When histrelin is administered to treat central pre cocious puberty, the rate of secondary sexual maturation is slowed and in some cases there is a reversal of maturation which occurs before i nitiation of treatment. Of equal importance, histrelin therapy appears to have decelerating effects on skeletal maturation, allowing more st atural growth; an increase in final adult height is predicted from ava ilable data, but will need to be confirmed in long term.follow-up stud ies currently being undertaken. The most common adverse event reported during histrelin therapy was a skin reaction at the site of subcutane ous injection. Few patients have discontinued therapy because of any a dverse event. Although experience with histrelin is limited, the absen ce of effective clinically available alternatives and the demonstrated efficacy of histrelin justifies its place as a first-line therapy for patients with central precocious puberty.