Subcutaneous Palliative treatment of advanced prostate cancer
Adult: As implant delivering approx 50 mcg histrelin acetate per day: Surgically insert 1 implant every 12 months in the inner aspect of the upper arm.
Subcutaneous Central precocious puberty
Child: ≥2 years As implant delivering approx 65 mcg histrelin acetate per day: Surgically insert 1 implant every 12 months in the inner aspect of the upper arm. Discontinue at the onset of puberty, approx 11 years for females and 12 years for males.
Contraindications
Pregnancy.
Special Precautions
Patient with history of CV diseases (e.g. cardiac failure, QTc prolongation, electrolyte disturbances), psychiatric disorders, history of seizures, epilepsy, cerebrovascular disorders, CNS anomalies or tumours, CVA, diabetes mellitus, metastatic vertebral lesions, urinary tract obstruction. Children.
Adverse Reactions
Significant: Transient increase in testosterone and estradiol levels (manifested as worsening of symptom), increased risk of CV disease (e.g. MI, stroke, QTc prolongation), hyperglycaemia, increased risk of diabetes mellitus, spinal cord compression, ureteral obstruction, tumour flare, psychiatric reactions (e.g. emotional lability, depression), convulsions. Rarely, pituitary apoplexy (manifested as visual or mental disturbances, headache, vomiting, CV collapse). Gastrointestinal disorders: Constipation. General disorders and administration site conditions: Fatigue. Injury, poisoning and procedural complications: Insertion site reactions (e.g. bruising, erythema, pain, oedema, protrusion of implant, pruritus, soreness, tingling). Investigations: Increased weight. Nervous system disorders: Headache. Psychiatric disorders: Insomnia. Renal and urinary disorders: Renal impairment. Reproductive system and breast disorders: Gynecomastia, erectile dysfunction, testicular atrophy, decreased libido. Skin and subcutaneous tissue disorders: Keloid-like scar. Vascular disorders: Hot flashes.
Monitor testosterone, prostate-specific antigen, blood glucose, HbA1c levels; signs and symptoms of CV reactions including electrolyte levels and ECG in patients with prostate cancer. Monitor LH, FSH, testosterone and estradiol levels, 1 month after implantation then every 6 months thereafter; height and bone age every 6-12 months; development and worsening of psychiatric symptoms in patients with CPP.
Drug Interactions
May increase risk of convulsions with SSRI, bupropion.
Lab Interference
Interfere with laboratory tests of pituitary gonadotropic and gonadal functions.
Action
Description: Histrelin is a synthetic nonapeptide analogue of gonadotropin releasing hormone (GnRH). It acts as an agonist of GnRH receptors in the pituitary gland, causing down-regulation and desensitisation of gonadotropes. Continuous administration results in decreased gonadotropin secretion and subsequent decrease of LH, FSH, testosterone and estradiol levels. Onset: Chemical castration: Within 2-4 weeks.
Slowed linear growth velocity: Approx 1 month. Duration: Approx 12 months. Pharmacokinetics: Absorption: Bioavailability: 92%. Time to peak plasma concentration: Approx 12 hours. Distribution: Volume of distribution: Approx 58.4 ± 7.86 L. Plasma protein binding: Approx 70%. Metabolism: Metabolised in the liver via C-terminal dealkylation and hydrolysis. Excretion: Terminal elimination half-life: Approx 4 hours.
Chemical Structure
Histrelin Source: National Center for Biotechnology Information. PubChem Database. Histrelin, CID=25077993, https://pubchem.ncbi.nlm.nih.gov/compound/Histrelin (accessed on Jan. 23, 2020)
Storage
Store between 2-8°C. Do not freeze. Protect from light.
Follow applicable procedures for receiving, handling, administration, and disposal. Wear gloves during receiving, unpacking, and placing in storage.
L02AE05 - histrelin ; Belongs to the class of gonadotropin releasing hormone analogues. Used in endocrine therapy.
References
Anon. Histrelin. AHFS Clinical Drug Information [online]. Bethesda, MD. American Society of Health-System Pharmacists, Inc. https://www.ahfscdi.com. Accessed 03/04/2018.Anon. Histrelin. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 03/04/2018.Buckingham R (ed). Histrelin. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 03/04/2018.Supprelin LA Implant (Endo Pharmaceuticals Solutions Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 03/04/2018.Vantas Implant (Endo Pharmaceuticals Solutions Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 03/04/2018.