Introduction: Biosimilars are biological products that are very similar to their originators, with no meaningful differences in terms of efficacy, safety, and purity. Since the patents of some of the biologics used to treat patients with psoriasis have expired, uptake of biosimilars provides a good opportunity to reduce the cost of treatment. Areas covered: In this review we summarize the stages in development of a biosimilar product, the main differences with the originator biologic, and their potential implications. We have also reviewed clinical trials of biosimilars approved for the treatment of psoriasis. Expert opinion: Because of efficacy and convenience of administration, adalimumab biosimilars will be used to greater extent than etanercept or infliximab to treat patients with moderate-to-severe psoriasis. The pharmacokinetics, efficacy, safety and immunogenicity of approved biosimilars are equivalent to those of their reference products in clinical trials, and multiple-switch studies are intended to provide evidence in support of FDA-required interchangeability. Non-medical switching is expected to become frequent, and the nocebo effect will be relevant. Traceability of biologics is an essential requirement to gather relevant information on their long-term efficacy and safety, especially when multiple switches occur.
Keywords: Biosimilars; TNF inhibitors; adalimumab; biologics; etanercept; hidradenitis suppurativa; infliximab; interchangeability; psoriasis; switching.