Biologics and biosimilars.

Biological drugs are large, complex glycoprotein molecules produced in living organisms. Revolutionary treatments for many conditions, biologics used in dermatology will face patent expiration, opening opportunities for competitive versions. Biologic drugs are so complex such that it is impossible to reproduce them exactly. Biosimilars are designed to be highly similar, though not identical, to the innovator product. Because biosimilars are not exact replicates of innovator biologics, guidelines have suggested that biosimilars should be considered as unique therapeutic interventions, requiring unique names and physician notification prior to substitution. However, because biologics can never be replicated exactly, even innovator biologics have inherent batch-to-batch variability; when the second batch of innovator products were released, physicians began prescribing non-identical variants of biologics to their patients, accepting the possibility of variation in clinical effects. Unlike the variants in innovator products, biosimilars will provide clinical trial data demonstrating similar clinical effects, though there will always be some degree of uncertainty in how much clinical impact will be result from the variation in both innovator and biosimilar products. How biosimilars are approved and how we use biosimilars will need to balance considerations of cost and development time with the possibility of variation in biological response.