Afamelanotide Acetate (Monograph)

Drug class: Melanocortin Receptor Agonists

Medically reviewed by Drugs.com on Oct 10, 2024. Written by ASHP.

Introduction

Melanocortin 1 receptor (MC1-R) agonist.

Uses for Afamelanotide Acetate

Erythropoietic Protoporphyria

Used to increase pain-free light exposure in adults with a history of phototoxic reactions from erythropoietic protoporphyria.

Designated an orphan drug by FDA for treatment of erythropoietic protoporphyria.

Experts recommend afamelanotide for prevention of phototoxic symptoms in erythropoietic protoporphyria.

Afamelanotide Acetate Dosage and Administration

General

Patient Monitoring

Perform a full body skin examination 2 times annually to monitor new and pre-existing skin pigmentary lesions.
Monitor the patient for 30 minutes after administration of each skin implant.

Dispensing and Administration Precautions

Afamelanotide must be administered by a healthcare professional who is proficient in the sub-Q implantation procedure and has completed training prior to administration.

Other General Considerations

Instruct patients to continue sun and light protective measures during treatment with afamelanotide for prevention of phototoxic reactions related to erythropoietic protoporphyria.

Administration

Sub-Q Administration

Administer by sub-Q implantation.

Each implant contains 16 mg of afamelanotide. Insert each implant above the anterior supra-iliac crest using aseptic technique.

Use the SFM Implantation Cannula or another implantation device determined suitable by the manufacturer to insert implant. Consult manufacturer labeling for detailed information on the implantation procedure.

Dosage

Available as afamelanotide acetate; dosage expressed in terms of afamelanotide.

Adults

Erythropoietic Protoporphyria

Sub-Q

Insert a single implant (containing 16 mg of afamelanotide) sub-Q once every 2 months.

Special Populations

Hepatic Impairment

No dosage recommendations at this time.

Renal Impairment

No dosage recommendations at this time.

Geriatric Use

No dosage recommendations at this time.

Cautions for Afamelanotide Acetate

Contraindications

Hypersensitivity to the active drug or any excipients.

Warnings/Precautions

Skin Monitoring

Afamelanotide can cause generalized increased skin pigmentation and darkening of pre-existing nevi and ephelides.

Perform a full body skin examination 2 times annually to monitor new and pre-existing skin pigmentary lesions.

Specific Populations

Pregnancy

No data available to evaluate for drug-associated risk of major birth defects, miscarriage, or adverse fetal or maternal outcomes.

No adverse developmental effects observed in rats.

Lactation

Not known if excreted into breast milk. Effects on the breast-fed infant and on milk production not known. Consider developmental and health benefits of breastfeeding along with the mother's clinical need for the drug, and the potential for adverse effects on the breast-fed child from the drug or from the untreated maternal condition.

Pediatric Use

Safety and efficacy not established.

Geriatric Use

Insufficient number of patients ≥65 years of age included in clinical studies to assess differences in response compared to younger adults. Other reported experience indicates no difference in response between geriatric patients and younger adults.

Hepatic Impairment

Effect on pharmacokinetics not known.

Renal Impairment

Effect on pharmacokinetics not known.

Common Adverse Effects

Most common adverse effects (>2%) include implant site reaction, nausea, oropharyngeal pain, cough, fatigue, dizziness, skin hyperpigmentation, somnolence, melanocytic nevus, respiratory tract infection, non-acute porphyria, skin irritation.

Drug Interactions

Formal drug interaction studies not conducted.

Afamelanotide Acetate Pharmacokinetics

Absorption

Bioavailability

Peak plasma concentrations attained a median of 36 hours post-implantation.

Following a single sub-Q implantation, last measurable plasma concentrations observed 96 hours post-dose in the majority of patients.

Distribution

Extent

Not known if distributed into breast milk.

Elimination

Metabolism

Not fully characterized; may undergo hydrolysis.

Half-life

Approximately 15 hours.

Stability

Storage

Sub-Q

Implant

2—8ºC protected from light.

Actions

Melanocortin receptor agonist; predominantly binds to melanocortin 1 receptor (MC1-R).
Synthetic tridecapeptide and structural analog of α-melanocyte stimulating hormone (α-MSH).
Increases skin production of eumelanin independently of exposure to sunlight or artificial ultraviolet (UV) light.

Advice to Patients

Instruct patients to continue sun and light protective measures during treatment with afamelanotide for prevention of phototoxic reactions related to erythropoietic protoporphyria.
Inform patients that pre-existing nevi and ephelides may darken with afamelanotide treatment. To monitor new and pre-existing skin pigmentary lesions, a full body skin examination is recommended 2 times annually.
Advise patients to contact their healthcare provider if the implant is expelled.
Inform patients that the dressing may be removed from the insertion site after 24 hours. Instruct patients to monitor the insertion site and report any reactions to their healthcare provider.
Advise patients to inform their clinician of existing or contemplated concomitant therapy, including prescription and OTC drugs and dietary or herbal supplements, as well as any concomitant illnesses.
Advise women to inform their clinician if they are or plan to become pregnant or plan to breast-feed.
Inform patients of other important precautionary information.

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.