ORIGINAL ARTICLE Treatment of refractory adult-onset pityriasis rubra pilaris with TNF-alpha antagonists: a case series S Garcovich, †, * AR Di Giampetruzzi, ‡ G Antonelli, ‡ A Garcovich, † B Didona ‡ † Department of Dermatology, Policlinico Agostino Gemelli, Catholic University Sacred Heart, Rome ‡ Istituto Dermopatico dell’Immacolata, IRCCS Foundation, Dermatology, First Division, Rome, Italy *Correspondence: S Garcovich MD. E-mail: simgarko@yahoo.it Abstract Background Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis with frequent clinical presentation as erythroderma. Conventional systemic treatment is often unsatisfactory and limited by long-term toxicity. The use of tumour necrosis factor (TNF) antagonists has been reported previously in single cases, but lacking long-term follow- up or comparison between different biological agents. Objectives To assess the long-term efficacy and safety of TNF-alpha antagonist, infliximab and etanercept, either in monotherapy or in combination therapy of severe, refractory adult-onset PRP. Methods Seven patients of adult-onset PRP, six newly diagnosed type-I and 1 type-II, which were resistant or ineligible to conventional systemic treatment, received a single course of infliximab or etanercept therapy, alone or in combination with low-dose acitretin (>0.25 mg / kg / daily). After complete remission and treatment discontinuation, a follow-up period of 12 months was evaluated for relapses. Results Six patients obtained complete remission after a single course of anti-TNF-alpha therapy: mean therapy duration was 19.3 weeks (range 6–48 weeks). All patients obtained significant clearing (>75% of body surface area) of skin lesions at week 12. Two patients with marked keratoderma developed localized disease recurrence during treatment. During follow-up, only a single patient, affected by type II PRP, had disease relapse. Conclusions Both TNF-alpha antagonists proved successful for the treatment of refractory, adult-onset PRP, yielding complete and persistent clinical responses in type-I PRP. Infliximab was associated with a more rapid onset of action, while treatment duration was comparable with etanercept. PRP type II warranted long-term therapy and showed relapse after drug discontinuation. Recieved: 3 September 2009; Accepted: 26 October 2009 Keywords etanercept, infliximab, pityriasis rubra pilaris, recurrence Conflict of interest None declared. Introduction Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis of unknown aetiology characterized by follicular erythema and scaling, palmoplantar keratoderma and variable progression to erythroderma. As described by Griffiths, classical type I PRP is the most frequent form in adults showing adult onset, favour- able course over 1–3 years and possible spontaneous resolution. Type II PRP is a rare form (5% of cases) occurring in adults and presenting atypical morphological features and long disease duration. 1 Sharing many similarities with psoriasis on clinical and histological grounds PRP can sometimes represent a thera- peutic challenge. We report the efficacy of TNF-alpha antago- nists Infliximab and Etanercept for the treatment of seven cases of adult-onset PRP, which were resistant to or ineligible to con- ventional systemic treatments. Materials and methods Seven patients of adult-onset PRP attended our dermatological departments during the time period 2008–2009, with demographic and clinical characteristics summarized in Table 1. Six patients were newly diagnosed as type I adult-onset PRP according to Griffiths classification, affecting more than 30% of body surface area (BSA) and confirmed by histology. (Fig. 1a,c). Erythrodermic involvement was present in six patients. Marked palmo-plantar ª 2009 The Authors JEADV 2010, 24, 881–884 Journal compilation ª 2009 European Academy of Dermatology and Venereology DOI: 10.1111/j.1468-3083.2009.03511.x JEADV