During this cost-conscious time, many patients and other healthcare payors are opting for generic versions of branded pharmaceuticals. Biopharmaceuticals have claimed a place in the spotlight, but the US currently has no regulatory pathway for biosimilars. That could change after FDA releases its final guidance on follow-on biologics later this year.

EMA published guidelines for follow-on biologics in 2005, and FDA has been studying its peer’s approach. So far it appears that FDA will follow EMA’s strategy of taking a product-specific approach to approving follow-on biologics. “Given the complex nature of biologics, it’s unlikely that a ‘one size fits all’ systematic assessment of biosimilarity can be developed,” wrote Janet Woodcock, director of the Center for Drug Evaluation and Research, and her colleagues in The New England Journal of Medicine. The agency will likely examine not only the manufacturing process for the therapies, but also the populations for whom the drugs are intended.

Companies that hope to enter this potentially lucrative market have argued that analytical characterization methods have improved to the point where they can establish similarity between a branded and a follow-on product. Some firms have argued that these methods could reduce the need for clinical trials. But FDA does not seem convinced that characterization methods have advanced far enough. Rather, “additional animal and clinical studies will generally be needed for protein biosimilars for the foreseeable future,” they wrote in the article, but “the scope and extent of such studies may be reduced further if more extensive fingerprint-like characterization is used.”

Ultimately, we won’t be able to predict the shape of the follow-on biologics industry in the US until FDA publishes its final guidance. Large-molecule therapies are more complex than small-molecule products, and it remains to be seen how burdensome the agency’s approval requirements will appear to the industry. Firms will have to weigh regulatory costs against the potential future profits before taking the plunge into this new market.