ORIGINAL ARTICLE Treatment of palmoplantar psoriasis with infliximab: a randomized, double-blind placebo-controlled study R. Bissonnette, †, * Y. Poulin, ‡ L. Guenther, § C.W. Lynde, – C. Bolduc, † S. Nigen † † Innovaderm Research Inc., Sherbrooke est, Montreal, QC, Canada ‡ Centre de Recherche Dermatologique du Que ´ bec Me ´ tropolitain, Que ´ bec, QC, Canada § The Guenther Dermatology Research Centre, London, ON, Canada – Lynderm Research, Markham, ON, Canada *Correspondence: R. Bissonnette. E-mail: rbissonnette@innovaderm.ca Abstract Background Palmoplantar psoriasis is a difficult to treat variant of plaque psoriasis. Objective To study the safety and efficacy of infliximab in non-pustular palmoplantar psoriasis. Methods Patients with non-pustular palmoplantar psoriasis affecting at least 10% of their palms and soles and with a modified palmoplantar psoriasis area and severity index (m-PPPASI) of at least eight were recruited. Patients were randomized (1:1) to receive infliximab 5 mg/kg or placebo at weeks 0, 2 and 6. Patients initially randomized to placebo received infliximab at weeks 14, 16 and 20 whereas patients randomized to infliximab received additional infliximab infusions every 8 weeks until week 22. Results Twenty four (24) patients were randomized in this study. At week 14, 33.3% and 66.7% of patients treated with infliximab achieved m-PPPASI 75 and m-PPPASI 50 respectively compared to 8.3% for both m-PPPASI 75 (P = 0.317) and m-PPPASI 50 (P = 0.009) for patients randomized to placebo. A reduction of 50.3% in the mean surface area of palms and soles affected with psoriasis was seen at week 14 in patients randomized to infliximab as compared to an increase of 14.9% in patients randomized to placebo (P = 0.009). Conclusions This pilot study did not reach its primary endpoint of m-PPPASI 75 at week 14. However, infliximab was observed to be more efficacious than placebo in improving PPSA and with respect to the percentage of patients reaching m-PPPASI 50 at week 14. Larger and longer term studies are needed for severe patients to better assess the efficacy of infliximab in palmoplantar psoriasis. Received: 15 April 2010; Accepted: 12 January 2011 Conflicts of interest Dr Bissonnette has been a speaker, consultant, investigator and / or advisory board member for Abbott Laboratories, Amgen-Wyeth, Astellas Pharma, Centocor, Janssen Ortho, Novartis and Schering-Plough. He has received compensation in the form of grants and / or honoraria from these companies. No conflicts of interest exist. Dr Poulin has been a speaker, consultant, investigator and / or advisory board member for Abbott Laboratories, Amgen-Wyeth, Astellas Pharma, Centocor, Ortho Biotech, EMD Serono and Schering-Plough. He has received compensation in the form of grants and / or honoraria from these companies. No conflicts of interest exist. Dr Guenther has been a speaker, consultant, investigator and advisory board member for Abbott Laboratories, Amgen-Wyeth, Astellas Pharma, Centocor, Janssen Ortho, Novartis and Schering Plough and Schering-Plough Canada. She has received compensation in the form of grants and / or honoraria from these companies. No conflicts of interest exist. Dr Lynde has been a speaker, consultant, investigator and / or advisory board member for Abbott Laboratories, Amgen-Wyeth, Astellas Pharma, Centocor, Janssen Ortho and Schering-Plough. He has received compensation in the form of grants and / or honoraria from these companies. No conflicts of interest exist. Dr Bolduc has been a speaker, consultant, investigator or advisory board member for, Abbott Laboratories, Amgen- Wyeth, Biogen, Celgene, Centocor, Galderma, Genentech, Leo Pharma, Medimmune, Novartis and Schering-Plough Canada. She has received compensation in the form of honoraria from these companies. No conflicts of interest exist. Dr Nigen has been a speaker, consultant, investigator and / or advisory board member for Abbott Laboratories, Amgen-Wyeth, Astellas Pharma, Centocor, Janssen Ortho, Novartis and Schering-Plough Canada. He has received compensation in the form of honoraria from these companies. No conflicts of interest exist. ª 2011 The Authors JEADV 2011, 25, 1402–1408 Journal of the European Academy of Dermatology and Venereology ª 2011 European Academy of Dermatology and Venereology DOI: 10.1111/j.1468-3083.2011.03984.x JEADV