Afamelanotide
Indications
Afamelanotide is used for:
Phototoxicity, Anaphylaxis & Erythropoietic, Protoporphyria
Adult Dose
Phototoxicity/Anaphylaxis & Erythropoietic Protoporphyria
Indicated for prevention of phototoxicity and anaphylactoid reactions in adults with erythropoietic protoporphyria (EPP)
16 mg implanted SC q2Months
Child Dose
Renal Dose
Administration
SC Implant Preparation
Equipment required
Afamelanotide implant
SFM implantation cannula (contact manufacturer for other suitable implantation devices)
Sterile gloves
Local anesthetic, needle, and syringe
Blunt forceps suitable for removing implant from vial
Sterile gauze, adhesive bandage, pressure bandage
SC Implant Administration
Also see prescribing information for instructions and diagrams
Step 1
Remove implant from refrigerator and allow to gradually warm up to ambient temperature
Remove the seal and stopper from the glass vial containing implant; remove implant from vial using the blunt forceps under aseptic conditions and place on sterile gauze
Step 2
Position patient in a comfortable reclined supine position
Identify the insertion site 3-4 cm above the anterior suprailiac crest and disinfect the skin surface
Step 3 (optional)
Anesthetize insertion area if deemed necessary and in consultation with the patient
Step 4
While pinching skin at insertion site, insert the cannula with the bevel facing upwards (away from the abdomen) at a 30-45º angle into the SC layer
Advance the cannula 2 cm into the SC layer
Step 5
Remove stylet (obturator) from the cannula, maintaining aseptic precautions
Load the implant into the cannula
Using the stylet (obturator), gently push the implant down the full length of the cannula’s shaft
Step 6
Apply pressure to implant site while removing the stylet (obturator) and cannula
Verify that no implant or implant portion remains in the cannula
Step 7
Verify the correct insertion and placement of the implant by palpating the skin overlying the implant
Step 8
Apply dressing to the insertion site
Leave dressing in place for 24 hr
Step 9
Monitor the patient for 30 minutes after implant administration
Contra Indications
Precautions
Owing to its pharmacologic effect, afamelanotide may lead to generalized increased skin pigmentation and darkening of preexisting nevi and ephelides; twice-yearly full-body skin examination recommended to monitor preexisting and new skin pigmentary lesions
Pregnancy-Lactation
Pregnancy
No data are available regarding use in pregnant women to evaluate for any drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcome
Animal data
In animal reproductive and development toxicity studies, no adverse developmental effects were observed with administration during organogenesis to pregnant rats at SC doses up to 12 times the maximum recommended human dose (MRHD)
Lactation
No data are available on the presence of afamelanotide or any of its metabolites in human or animal milk, effects on the breastfed infant, or on milk production
Interactions
Adverse Effects
Side effects of Afamelanotide :
>10%
Implant site reaction (21%)
Nausea (19%)
1-10%
Oropharyngeal pain (7%)
Fatigue (6%)
Skin hyperpigmentation (4%)
Dizziness (4%)
Melanocytic nevus (4%)
Respiratory tract infection (4%)
Somnolence (2%)
Nonacute porphyria (2%)
Skin irritation (2%)
Mechanism of Action
Erythropoietic protoporphyria is a rare disorder caused by mutations leading to impaired activity of ferrochelatase, an enzyme involved in heme production; decreased ferrochelatase activity leads to protoporphyrin IX (PPIX) accumulation in the body; light reaching the skin can react with PPIX, causing intense skin pain and skin changes (eg, redness, thickening)
Afamelanotide, a melanocortin-1 receptor (MC1-R) agonist, increases production of eumelanin (the most common type of melanin) in the skin independent of exposure to sunlight or artificial light sources