Inclusion Criteria:  Male or female patient with a molecular-genetically confirmed diagnosis of XP-C; Aged 18-75 years.  Exclusion Criteria:  Known allergy to afamelanotide or the polymer contained in the implant; Presence of severe hepatic disease or hepatic impairment; Renal impairment; Any other medical condition which may interfere with the study protocol; Female who is pregnant (confirmed by positive urine beta-Human chorionic gonadotropin pregnancy test) or lactating; Females of child-bearing potential (pre-menopausal, not surgically sterile) not using highly effective contraceptive measures with a failure rate of less than 1% per year when used consistently and correctly (i.e. oral contraceptives, intrauterine device) or a life-style excluding pregnancy, for up to three months after the last implant administration; Sexually active man with a partner of child-bearing potential (pre-menopausal, not surgically sterile) who is not using highly effective contraceptive measures, as described above; Use of any other prior and concomitant therapy which may interfere with the objective of the study, within 30 days prior to the Screening visit; Participation in a clinical trial for an investigational agent within 30 days prior to the Screening visit.