With the news of availability of generic Lipitor, a cholesterol lowering drug, sales of the prescription brand have plummeted, as expected. Is generic Lipitor really the same as prescription Lipitor? Consider this:
Behind every pill is a story. US patents grant the inventor a 20 year property right; only the inventor can manufacture and sell the medicine. When the patent expires, anyone can produce and sell it. The Food and Drug Administration arguably has the most rigorous regulatory oversight in the world for both generic and brand name prescriptions, to ensure that the drugs are safe and effective.
But the devil is in the details. Yes, any company can manufacture a generic drug after patent expiration and must prove to the FDA that it is “bioequivalent” to the brand name pill. Are “bioequivalent” pills “identical”? Consider this. In order to produce it, the generic manufacturer must know how to make the active ingredient, on a multi-ton scale, how to add the inert, inactive components, and how to coat the pill. Each of these steps is critical for the final product to be as safe and effective as the brand name drug.
How do they know how to do this? The generic manufacturer refers to the original patents, along with other scientific articles. But here’s the rub. These patents are crafted so that just enough information is revealed to convince the US Patent and Trademark Office that the invention is novel and “non-obvious”, while maintaining “trade secrets” including details about large-scale manufacturing.
So each aspiring manufacturer of a generic drug needs to figure out how to mimic the original brand name process for each step. Not surprisingly, different companies can accomplish this using various methods, whether to synthesize the active ingredient, formulate the inactive ingredients or coat the pill.
Why should you care? Because there is mounting evidence that variation from generic to generic produced in the US, and more importantly, those produced worldwide, can determine the safety and effectiveness of a medication. For example, generic forms of the antidepressant Wellbutrin XL 300 were found to release the active drug at different rates compared to the brand name, measured by an independent testing laboratory. In a survey of twenty foreign sources of generic simvastatin, a cholesterol-lowering drug, researchers found that a 20 mg dose actually ranged from 29.7 to 40.1 mg. These medicines can often be purchased over the internet without a prescription. More than doubling the prescribed dosage could result in more adverse side effects. The effectiveness of these medications can also be reduced by differences in “clumping” of the active ingredients and the pill coating – this changes how long it takes for the pill to dissolve and release the drug.
So buyer beware. Generic drugs can be safe and effective, particularly for those produced in the US, but an informed patient working together with their physician will ensure the best outcome. Online social networking for patients and healthcare workers is one of the best ways to make this happen, such as PatientsLikeMe. If you are fortunate enough to have a good health insurance plan, choosing the brand name prescription will ensure uniformity and reliability of the medicine. However, if you and your doctor choose a generic equivalent, be sure to communicate with your health care providers about any potential adverse side effects. To make sure that the medicine is working, be sure that you follow up with your doctor for any required tests. Keep a record of any changes you note in your reaction to the medicine – see “Tips on Generics“. And please check with your pharmacist – be sure that their source of any generic is consistent, as there is no requirement to notify you if they do choose another manufacturer.
A generic drug produced in the US, while “bioequivalent” to the brand name drug, may or may not be “identical”.
A version of this article was published at NJ Voices.