Jonathan Kay, MD


June 24, 2011

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Hello. I'm Dr. Jonathan Kay, Professor of Medicine at the University of Massachusetts (UMASS) Medical School and Director of Clinical Research in the Division of Rheumatology at UMASS Memorial Medical Center in Worcester, Massachusetts. Welcome to this Medscape blog. Today we're going to talk about biosimilar drugs. Biosimilars are biopharmaceuticals that are defined as being sufficiently similar to innovator biopharmaceuticals. These can be small proteins such as insulin or erythropoietin, which are already available in the United States market, or they can be biosimilars of large biopharmaceuticals such as monoclonal antibodies.

Although we think that these are elements of the future, biosimilars for etanercept and rituximab are already available in other countries. There is a biosimilar etanercept that is manufactured in Shanghai, China. It is also available under the brand name of Etanar in Colombia. At the European League Against Rheumatism 2011 Annual Scientific Congress, an abstract was presented about the pharmacoeconomics of the use of Etanar compared with other biologic drugs for rheumatoid arthritis in Colombia.[1] In Colombia, Etanar is priced at $17,000/year compared with $20,000/year for Enbrel. When looking at quality-adjusted life years, the dollars per quality-adjusted life years are significantly lower for Etanar compared with that for Enbrel in Colombia. I was told that there are about 400 patients in Colombia already receiving Etanar for treatment of rheumatoid arthritis compared with several thousand who are being treated with Enbrel.

In India, there is a biosimilar rituximab that has been available since 2007, marketed by Dr. Reddy's, which is a large generic pharmaceutical company. It is also approved in India for the treatment of rheumatoid arthritis. Furthermore, 2 large generic pharmaceutical companies, Teva Pharmaceuticals in Israel and Sandoz, the generic arm of Novartis, are about to conduct clinical trials in the United States and Western Europe for biosimilar rituximab. These compounds are soon to be studied and, presumably, soon to be available in the United States and Western Europe.

What about the approval process for these compounds? The European Medicines Agency has issued guidance on what kinds of studies are necessary for biosimilar monoclonal antibodies. These include studies in animals and pharmacokinetic and pharmacodynamic studies, as well as in vivo studies in humans. There are chemical analyses required to show similarities, and then there will be an abbreviated clinical trial pathway that will be determined. In the United States, the Patient Protection and Affordable Care Act that was signed into law in March was designed to include a pathway for a biosimilar drug approval process in the United States. This mandates a single 3- to 6-month clinical trial, possibly more, followed by studies to look at immunogenicity to determine whether a compound can be substituted by a pharmacist for the branded biopharmaceutical. This act outlines a pathway for an abbreviated biologics license approval process, but this process has not yet been carried out in the United States.

Whether this will lead to less expensive biologic therapies for the rheumatic diseases remains to be answered. Will this benefit our patients with drugs that are as effective for the treatment of rheumatic diseases? It will be interesting over the next several years to observe how this rolls out in the United States and Western Europe, and we will presumably see an increase in the availability of affordable medications for our patients with rheumatoid arthritis and other rheumatic diseases. I welcome your comments and questions, and look forward to seeing you on Medscape in the future.


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