Supplementary Material for: Topical statins in porokeratosis: Case Report with Focused Literature Review

Background: Porokeratosis is a disorder of keratinization linked to mevalonate pathway defects and often resistant to conventional therapy. Topical statins, which target this pathway directly, represent a rational mechanism-based treatment.
Case Presentation: A 63-year-old woman with disseminated superficial actinic porokeratosis (DSAP), refractory to calcipotriol and 5-fluorouracil, was treated with compounded simvastatin 2% cream twice daily. After six months, erythema and scale were markedly reduced; thin papules flattened almost completely, whereas hyperkeratotic plaques improved only partially. Treatment was well tolerated without systemic adverse effects, and the patient was maintained on once-daily application to prevent relapse.
Literature Review: Evidence from 10 representative reports—including one randomised controlled trial and one controlled split-body study—shows reproducible benefit of topical statins across DSAP and selected other variants. Early inflammatory lesions often flatten fastest, whereas older hyperkeratotic plaques improve more slowly; relapse has been reported after discontinuation, supporting the use of maintenance therapy. Safety is favourable, largely mild local irritation, with rare events such as allergic contact dermatitis to simvastatin and transient creatine kinase elevation/myalgia. The role of cholesterol co-formulation remains uncertain: the RCT found no added benefit, while split-face and case reports suggest activity of cholesterol alone in limited contexts. Standardised formulations and larger controlled trials are needed.
Conclusion: Topical statins are a promising, low-toxicity therapy for porokeratosis. Larger, controlled studies are needed to standardize formulations, optimize maintenance, and confirm long-term safety.