Good luck convincing patients that generics equal brand-name drugs

Generic drugs have long carried a stigma for at least some people. Patients sometimes feel scared and shortchanged when prescribed them, and some physicians have been wary of their safety and efficacy, compared with brand-name counterparts.

This fall, results appeared from a trio of prospective, randomized studies that compared several generic forms of the antiepileptic drug lamotrigine against the brand-name compound, Lamictal, in patients with epilepsy. As reported earlier this month in a special session at the annual meeting of the American Epilepsy Society, and as I wrote up in a news article, the findings from all three studies consistently and clearly showed that the generic lamotrigine products tested in these three studies all performed identically to Lamictal by both their pharmacokinetic profiles and in their clinical safety and efficacy.

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Lamotrigine's chemical structure

A critic could quibble that the three studies involved relatively small numbers of patients (they included 34-48 subjects), that the treatment times were relatively brief (a matter of a few weeks), and the investigations were limited to just lamotrigine. But the neurologists who reported these findings, a pair of Food and Drug Administration staffers who deal with generics and spoke at the session, and two pharmacy researchers who also participated in the panel all agreed that these groundbreaking studies establish an unprecedented level of confidence in not just the generic products tested but for generic drugs in general.

As Dr. Michael Privitera, director of the Epilepsy Center at the University of Cincinnati and a lead investigator for two of the three studies, told me, controlling seizures in epilepsy patients is a stringent test of drug efficacy and similarity. If generic forms of lamotrigine behave indistinguishably from Lamictal, then it’s very reasonable to expect that virtually any generic form of any brand-name drug used in medicine is also a good mimic if it recently passed FDA muster. His only caveat was selected drugs with very unusual pharmacokinetic properties, such as phenytoin – another antiepileptic drug, which has saturation kinetics making it a special case that requires additional, customized testing to prove equivalence between the generic and brand-name form.

But as he and others at the session highlighted, equivalent pharmacologic properties of generic and brand-name forms of a drug tell just part of the story. They may act the same once inside patients’ bodies, but what’s also important is how patients regard these drugs from the neck up. Psychological factors play a role in how patients perceive and use different forms of chemically identical products. Differences in pill size, shape, and color can confuse patients, and just knowing that a drug is a generic could possibly trigger anxiety in a patient that might perhaps produce a seizure or disrupt their pill-taking behavior. Several clinicians at the session spoke of certain patients who have begged them to specify the brand-name drug on their prescriptions. On the other hand, a generic’s lower price often encourages more conscientious use, a phenomenon documented in a database review reported at the session by pharmacoepidemiologist Joshua J. Gagne, Pharm.D.

Madison Avenue has known for years that function and utility tell just part of the story when it comes to consumer goods. A Kia may be just as durable and effective for transporting someone as a Mercedes or BMW, but cheap isn’t always what a consumer wants or feels comfortable with. Generics that work indistinguishably from brand drugs are certainly attractive for the U.S. health care system and the majority of the American public, but the concept that generic is best will be tough to sell to everyone.

mzoler@frontlinemedcom.com

On Twitter @mitchelzoler