Sinecatechins (Polyphenon E) ointment for treatment of external genital warts and possible future indications

Introduction: Sinecatechins was the first botanical drug licensed for treatment in humans in the US. It is approved for the topical treatment of external genital and perianal warts. Some properties of the polyphenolic components included in sinecatechins suggest additional therapeutic potential for other skin diseases. Areas covered: Studies and articles describing therapeutic application of sinecatechins or green tea polyphenols in viral and proliferative skin diseases or investigating molecular activities relevant for the mode of action were identified by a PubMed search using 'sinecatechins', 'green tea polyphenols', 'polyphenon E' and 'EGCG', each combined with 'skin cancer' and 'genital warts' as search criteria. Although a number of molecular mechanisms of green tea polyphenols were described, the exact mode of action operative in regression of genital warts is not yet clear. It may involve both antiproliferative, pro-apoptotic and antiviral activities that probably also account for efficacy against other skin disorders. Expert opinion: In addition to treatment of skin tumors, sinecatchins may also be used to protect against photocarcinogenesis. Considering antioxidative properties of polyphenols and the capability to enhance DNA repair, sinecatechins appears attractive for primary prevention of nonmelanoma skin cancer either as additive in sunscreens or as dietary supplement for oral administration.