Supprelin La (histrelin acetate)

The usual adult dosage of histrelin acetate for the palliative treatment of advanced prostate cancer is one 50-mg implant inserted subcutaneously every 12 months. The 50-mg implant delivers 41 mg of histrelin and provides continuous release of 50 mcg of histrelin acetate (41 mcg of histrelin) daily for 12 months of hormonal therapy. The implant should be removed 12 months after insertion; the implant has been designed to allow for a few additional weeks of histrelin release to allow for flexibility in scheduling implant removal. At the time the implant is removed, another implant may be inserted to continue therapy.

Results of a phase 2, dose-ranging study in 42 patients with advanced prostate cancer indicate that the use of 2 or 4 implants does not confer any additional benefit in suppression of testosterone beyond that produced by a single implant.

Histrelin acetate is administered as an implant that is inserted subcutaneously in the inner aspect of the upper arm. The manufacturer's labeling should be consulted for proper methods of inserting and removing histrelin acetate implants. Importance of adhering to recommended procedures to minimize the risk and complications associated with surgical insertion and removal. (See Cautions: General Precautions.)

A kit containing many of the supplies necessary to insert and/or remove the implant is provided with the implant; this kit does not require refrigeration. Histrelin acetate implants should be refrigerated at 2-8degreesC until the day of the procedure. Once removed from refrigeration, the vial containing the implant (still in its unopened pouch and carton) may remain at room temperature for up to 7 days, if necessary, before being used. The implant vial should not be opened until just before the time of insertion. If not used in that time, the packaged implant may again be properly refrigerated until the expiration date on the carton.

No dosing information is available for this tab.

No dosing information is available for this tab.

No formal drug interaction studies have been performed.

There are no contraindication interactions for this drug.

There are no severe interactions for this drug.

There are no moderate interactions for this drug.

Known hypersensitivity to histrelin or any ingredient in the formulation, other gonadotropin-releasing hormone (GnRH) agonists, or GnRH.

Contraindicated in women who are or may become pregnant.

• Pregnancy

There are no severe contraindications for this drug.

• Lower seizure threshold
• Seizure disorder

Local or insertion site reactions were reported in 13.8% of patients after insertion of a histrelin acetate implant in a single study in 138 patients. Most of these reactions were associated with initial insertion or removal and insertion of a new implant. These reactions typically began and resolved within the first 2 weeks following implant insertion. However, in almost 3% of patients, local reactions developed after the first 2 weeks or persisted beyond 2 weeks. Local reactions reported in 2% or more of patients in this study included bruising, pain/soreness/tenderness, and erythema.

Adverse systemic effects associated with testosterone suppression occurring in 2% or more of patients receiving a histrelin acetate implant in 2 studies in a total of 171 patients included hot flushes (flashes), testicular atrophy, gynecomastia, erectile dysfunction, and decreased libido. Other adverse systemic effects occurring in 2% or more of patients included fatigue, renal impairment, constipation, headache, insomnia, and weight loss.

Less Frequent

• Behavioral disorders
• Depression
• Hypersensitivity drug reaction

Rare or Very Rare

• Acute generalized exanthematous pustulosis
• Breakage of implant
• DRESS syndrome
• Idiopathic intracranial hypertension
• Seizure disorder
• Stevens-johnson syndrome
• Suicidal ideation
• Toxic epidermal necrolysis

More Frequent

• Headache disorder
• Injection site sequelae
• Localized edema

Less Frequent

• Epistaxis
• Keratoderma
• Mastalgia
• Pruritus of skin
• Scar of skin

Rare or Very Rare

• Abnormal vaginal bleeding
• Aggressive behavior
• Dysmenorrhea
• Erythema
• Gynecomastia
• Irritability
• Mood changes
• Sensation of cold

No enhanced messaging available.

Not indicated for use in pediatric patients.

Category X. (See Cautions: Contraindications; Users Guide; and also see Fetal/Neonatal Morbidity/Mortality under Warnings/Precautions: Warnings, in Cautions.)

Not indicated for use in women. Not known whether histrelin is distributed into milk. Discontinue nursing or drug, taking into account the importance of the drug to the woman.

Clinical studies have been conducted principally in patients 65 years of age and older since prostate cancer occurs mainly in an older patient population.