Biosimilar Drugs Too Different to Bypass Testing

Published July 30, 2009

“Biologics,” or biologically produced drugs, constitute a huge and growing segment of the medical marketplace. They include insulin and many vaccines.

In 2008, more than 600 new biotechnology medicines, for more than 100 diseases, were in development in the United States. More than 300 other biologics already had been approved for use by the federal Food and Drug Administration.

Because biologics are used to treat a wide range of diseases, including cancer, multiple sclerosis, and rheumatoid arthritis, legislators and medical professionals are interested in bringing less-costly “generic” versions to the marketplace. A bill proposed by Rep. Henry Waxman (D-CA), the Promoting Innovation and Access to Life-Saving Medicine Act (HR 1427), would allow for the manufacture and distribution of “biosimilars,” or generic biologic drugs, following standards similar to those governing generic chemical drugs.

Guidelines for Generic Manufacture

In 1984, the Drug Price Competition and Patent Term Restoration Act, sponsored by Waxman and then-Rep. Orrin Hatch (R-UT), created an abbreviated approval process for generic chemical drugs.

Because the active ingredients in chemical generics are identical to those in the “innovator drugs,” or original name-brand medicines, it was possible to establish an approval process allowing generic manufacturers to piggyback on the research studies provided by the innovator companies. The ability to manufacture drugs that already had been extensively tested hastened the generic drugs’ entry into the marketplace, saving both time and money.

When chemical reactions are performed, the result is always the same. Combining two hydrogen molecules with one of oxygen always produces water.

No Margin for Error

This is not the case with biologics, which are “grown” (biologically engineered), not created by a simple chemical reaction. No two biologics created using different cell lines or different manufacturing processes ever turn out exactly the same.

That’s the problem with HR 1427. In mirroring the guidelines for generic chemical drugs, Waxman’s new bill assumes the copies of biologics made by follow-on manufacturers—though admittedly not identical—will be close enough to the originals to make extensive product testing before release unnecessary.

What is close enough for government work is not necessarily close enough for the treatment of patients. Small differences in drugs can have very profound effects on the body. Because biologics are huge, complex entities, predicting how small changes in them will affect safety, efficacy, and immunogenicity is not possible.

‘Biosimilars’ Are ‘Biodifferent’

Perhaps follow-on biologics should be called “biodifferent” rather than “biosimilar.” It is the differences that are of concern, not the similarities. These differences, no matter how minute, can have major implications for patients.

Physicians and patients need to be confident that any biosimilar approved by the FDA has been subjected to the same rigorous clinical testing as the innovator drug. Waxman’s bill would not provide that security.

Dr. Richard Dolinar ([email protected]) is a practicing endocrinologist and a senior fellow for health care policy at The Heartland Institute.

For more information …

House Resolution 1427, the Promoting Innovation and Access to Life-Saving Medicine Act: