The European Medicines Agency (EMA) is expected to release shortly for public consultation guidelines for biosimilars for monoclonal antibodies (mAbs). As the regulatory environment for biosimilar mAbs begins to be debated, how strong is their market potential?
EMA said the guideline, Similar Biological Medicinal Products Containing Monoclonal Antibodies, will soon be released for a five-month public consultation period. The agency offered few details and only said that the guideline “lays down the nonclinical and clinical requirements for monoclonal antibody-containing medicines claiming to be similar to another one already marketed” and that it will be published on the agency’s website “shortly.”
Certain industry groups have cited the need for guidelines. In September 2010, the European Generics Association (EGA), the trade association representing European generic-drug manufacturers, addressed the need for guidelines for biosimilar mAbs. “If healthcare systems are to continue to function long-term, we must address the importance of biosimilar monoclonal antibodies next,” said EGA Director General Greg Perry in a Sept. 2, 2010, press release. “Science for monoclonal antibodies is already here today, and our industry is expecting a workable guideline.”
It is widely expected that the EU guidelines will contain requirements for clinical trials of biosimilar mAbs, but the question is the extent of clinical testing that will be required for a biosimilar mAb given the increased complexity of these compounds compared with other therapeutic proteins that have been approved as biosimilars such as epoetin alpha, filgrastim, and human growth hormone. The level of clinical testing for biosimilar mAbs is important as it will be a cost factor for companies to consider for market entry to this segment and its competitive dynamics.
One of the first mAbs likely to be a biosimilar is rituximab, a drug to treat non-Hodgkin’s lymphoma and rheumatoid arthritis. The drug is marketed by Biogen Idec (Cambridge, MA) and Roche (Basel) as Rituxan and MabThera. The patents for rituxumab are expected to expire between 2015 and 2018 in the United States and in 2013 in the rest of the world, according to Biogen Idec’s 2009 annual report. Global sales of MabThera/Rituxan were CHF $6.1 billion ($6.1 billion) in 2009, according to Roche’s 2009 annual report. Teva Pharmaceuticals (Jerusalem) is developing a biosimilar version of rituxmab, according to a recent company investor presentation, and Dr. Reddy’s Laboratories (Mumbai) has developed a generic version for the Indian market, according to the company’s 2009 annual report.
Long term, biosimilar mAbs are an important piece for companies looking to capitalize in the biosimilars market. mAbs are the fastest growing segment in the biologics market overall, with sales expected to grow at a 9.5% compound annual growth rate (CAGR) or by $22.1 billion during 2008–2014, according to data from Datamonitor. In contrast, growth in therapeutic proteins will increase at a 3.6% CAGR or by $9.2 billion during 2008–2014.
But will strong growth for innovator mAbs eventually translate into a robust market for biosimilar mABs? That is the question yet to be answered. Biosimilar mAbs will continue to compete with innovator drugs and possibly too with second- or third-generation mAbs, or even with small molecules, depending on the indication. Also, biosimilar mAbs also must gain physician acceptance, particularly in such markets as the anticancer market.
Raising the bar for bioequivalency for biosimilar mAbs will not only dictate their clinical development but will also shape the market environment for them. Greater clinical requirements will raise the threshold for companies considering entering this market segment. Although at face value additional costs for clinical development would seem to be a negative for biosimilar players, it may be a necessary price to pay to make biosimilar mAbs a viable clinical option for physicians, particularly as they face an increasingly cost-constrained reimbursement environment for pharmaceuticals.