Author's personal copy REVIEW ARTICLE Therapeutic Strategies in Psoriasis Patients with Psoriatic Arthritis: Focus on New Agents Emily Yiping Gan • Wei-Sheng Chong • Hong Liang Tey Published online: 12 April 2013 Ó Springer International Publishing Switzerland 2013 Abstract Psoriatic arthritis affects approximately 6–42 % of patients with psoriasis. It is useful for physicians or dermatologists managing psoriasis patients to be aware of how to concurrently manage the joint manifestations, as it is preferable and convenient to use a single agent in such patients. However, only certain therapies are effective for both. Systemic agents, which can be used for both skin and joint manifestations, include methotrexate and ciclosporin. For the group of biologic agents, the tumor necrosis factor inhibitors such as adalimumab, etanercept, infliximab, golimumab and certolizumab are effective. Ustekinumab is a more recently developed agent belonging to the group of anti-IL-12p40 antibodies and has been shown to be efficacious. Newer drugs in the treatment armamentarium that have shown efficacy for both psoriasis and psoriatic arthritis consist of the anti-IL-17 agent, secukinumab, and a phosphodiesterase-4 inhibitor, apremilast. The other anti- IL-17 agents, ixekizumab and brodalumab, as well as the oral Jak inhibitor, tofacitinib, have very limited but promising data. This review paper provides a good overview of the agents that can be used for the concurrent management of skin and joint psoriasis. 1 Introduction Psoriasis is a multisystemic disease affecting 2–3 % of the population [1]. It predominantly presents with skin and joint manifestations. The proportion of patients with psoriasis who develops psoriatic arthritis (PsA) ranges from 6 to 42 % in different studies [2]. Psoriasis usually appears 8–10 years before PsA [1], although some patients present with PsA sine psoriasis. As both are immune-mediated chronic inflammatory diseases with a similar pathogenesis, concurrent treatment should be undertaken to minimize medication side effects and financial burden [3]. The aim of this paper is to review and summarize the various treatment options available for both psoriasis and PsA. 2 Method A PubMed search (without methodological search filters or limits) on the words ‘‘psoriasis’’ and ‘‘psoriatic arthritis’’ in the title and abstract was last performed on 5 November 2012. This yielded 34,279 results. Based on their titles and abstracts, 200 relevant articles were selected for review. Relevant results from the articles are summarized and presented in this narrative review. 3 Pathogenesis of Psoriasis and Psoriatic Arthritis 3.1 Overlap in Pathogenesis of Psoriasis and PsA Both the innate and adaptive immune systems are involved in the pathogenesis of psoriasis and PsA. T cell activation is a key component—specifically, T H 1T H 17 and T H 22 cells are upregulated in psoriasis lesions [4, 5]. Elevated levels of interferon (IFN)-c, tumor necrosis factor (TNF)-a and interleukin (IL)-12, components of the T H 1 pathway, are found in psoriasis [6]. Activated T cells migrate to the E. Y. Gan (&)  W.-S. Chong  H. L. Tey National Skin Centre, 1 Mandalay Road, Singapore 308205, Singapore e-mail: emily.ganyp@gmail.com BioDrugs (2013) 27:359–373 DOI 10.1007/s40259-013-0025-6