General Information

Fensolvi (leuprolide acetate) is a gonadotropin releasing hormone (GnRH) agonist.

Fensolvi is specifically indicated for the treatment of pediatric patients 2 years of age and older with central precocious puberty (CPP).

Fensolvi is supplied as a solution for subcutaneous administration. The recommended dose of Fensolvi is 45 mg administered by subcutaneous injection once every six months. Discontinue Fensolvi treatment at the appropriate age of onset of puberty. 

Mechanism of Action

Fensolvi (leuprolide acetate), a GnRH agonist, acts as a potent inhibitor of gonadotropin secretion (LH and follicle stimulating hormone (FSH)) when given continuously in therapeutic doses. Following an initial stimulation of GnRH receptors, chronic administration of leuprolide acetate results in downregulation of GnRH receptors, reduction in release of LH, FSH and consequent suppression of ovarian and testicular production of estradiol and testosterone respectively. This inhibitory effect is reversible upon discontinuation of drug therapy.

Side Effects

Adverse effects associated with the use of Fensolvi may include, but are not limited to, the following: 

• injection site pain
• nasopharyngitis
• pyrexia
• headache
• cough
• abdominal pain
• injection site erythema
• nausea
• constipation
• vomiting
• upper respiratory tract infection
• bronchospasm
• productive cough
• hot flush

Clinical Trial Results

The FDA approval of Fensolvi was based on an uncontrolled, open-label, single arm clinical trial in which 64 pediatric patients (62 females and 2 males, naïve to previous GnRH agonist treatment) with CPP received at least one dose of Fensolvi at a dosing interval of 24 weeks and were observed for
 12 months. The mean age was 7.5 years (range 4 to 9 years) at the start of treatment. In pediatric patients with CPP, Fensolvi reduced stimulated and basal gonadotropins to prepubertal levels. Suppression of peak stimulated LH concentrations to <4 IU/L was achieved in 87% of pediatric patients by month 6 and in 86% of patients by month 12. Suppression of estradiol or testosterone concentration to prepubertal levels at the 6-month assessment was achieved in 97% and 100% of patients, respectively. Suppression of estradiol or testosterone was maintained at the 12-month assessment with 98% (55/56 females) and  50% (1/2 males) maintaining suppression. Fensolvi arrested or reversed progression of clinical signs of puberty with reductions in growth velocity and bone age. Mean growth velocity decreased from  8.9 ± 13.1 cm/yr at 1 month to 6.9 ± 3.1 cm/yr at 6 months and to 6.4 ± 1.9 cm/yr at 12 months.