Dosing and uses of Supprelin LA, Vantas (histrelin)
Adult dosage forms and strengths
implant
- 50mg (Vantas)
- Vantas delivers ~50mcg/day
Palliative Treatment of Advanced Prostate Cancer
Vantas: 1 implant SC q12Months (50 mg/implant [delivers ~50 mcg/day])
Renal Impairment
CrCl: 15-60 mL/min: Dose adjustment not necessary
Porphyria (Orphan)
Treatment of acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria
Orphan indication sponsor
- Anderson, Karl E., M.D.; University of Texas Medical Branch at Galveston, Route J-09, 700 The Strand; Galveston, TX 77550
Administration
Insert SC in inner aspect of upper arm
When removing, confirm that the entire implant has been removed
Pediatric dosage forms and strengths
implant
- 50mg (Supprelin LA)
- Supprelin LA delivers ~65mcg/day
Central Precocious Puberty
Supprelin LA: 1 implant SC q12Months (50 mg/implant [delivers 65 mcg/day])
Administration
Insert SC in inner aspect of upper arm
When removing, confirm that the entire implant has been removed
Supprelin LA, Vantas (histrelin) adverse (side) effects
>10%
Hot flashes (65.5%)
1-10%
Fatigue
Headache
Insomnia
Constipation
Weight gain
Decreased libido
Erectile dysfunction
Gynecomastia
Testicular atrophy
Anemia
Hepatic disorder
Implant site reaction
Renal impairment<2% (important only)
- Fluid retention, peripheral edema, palpitations, ventricular extrasystoles
- Various pain
- Renal calculi
Postmarketing Reports
Cases of pituitary apoplexy (a clinical syndrome secondary to infarction of the pituitary gland) have been reported after the administration of gonadotropin-releasing hormone agonists
Severe liver injury reported; toxicity was reversible with the removal of the implant
General disorders and administration site conditions: Implant breakage
Nervous system disorders: Seizures
Warnings
Contraindications
Hypersensitivity
Women who may become or are currently pregnant, children
Cautions
Hyperglycemia and an increased risk of developing diabetes have been reported in men receiving GnRH agonists
Cases of spinal cord compression, which may contribute to weakness or paralysis with or without fatal complications, have been reported with GnRH agonists
Reports of MI, sudden cardiac death, and stroke in men treated with GnRH agonists
QT prolongation
- Androgen deprivation therapy may prolong the QT/QTc interval; consider whether the benefits of androgen deprivation therapy outweigh the potential risks in patients with congenital long QT syndrome, congestive heart failure, frequent electrolyte abnormalities, and in patients taking drugs known to prolong the QT interval
- Electrolyte abnormalities should be corrected
- Consider periodic monitoring of ECG and electrolytes
Pregnancy and lactation
Pregnancy category: X
Lactation: excretion in milk unknown; contraindicated
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Supprelin LA, Vantas (histrelin)
Mechanism of action
Synthetic nonapeptide analog & agonist of luteinizing hormone-releasing hormone/gonadotropin-releasing hormone (LHRH/GnRH); desensitizes response to endogenous LHRH
Pharmacokinetics
Release Rate: 50-60 mcg/day (Vantas); 65 mcg/day (Supprelin LA)
Peak Plasma: 1.1±0.375 ng/mL
Vd: 58.4±7.86 L (following 500 mcg bolus)
Bioavailability: 92% (adults
Duration: 1 year
Clearance: 174±56.5 mL/min
Protein binding: 70% ± 9%
Half-Life, terminal: 3.9±1 hr
Metabolism: Likely peptide hydrolysis
