Currently, 64% of all prescriptions filled in the United States are for generics. That percentage is expected to rise steeply over the next few years.
In 2007, the FDA approved manufacturers' plans to market 682 new generics in the United States. The agency still is working its way through a backlog of about 1,300 more applications from generic pharmaceutical manufacturers -- a tally that grows weekly. Among the widely prescribed medications expected to appear in generic form in the next few years: the migraine drug Imitrex; the cholesterol drug Lipitor; the blood pressure drug Norvasc; the gastrointestinal reflux drug Prevacid; and the psychiatric medications Risperdal, Effexor and Zyprexa.
At the same time, consumers are finding themselves constrained by their health plans, or lack of one.
In 2000, 22% of American workers with employer-sponsored health insurance had plans that made no distinctions in their coverage of medications: A patient's co-payment was the same whether she chose the expensive brand-name or the generic formulation of a drug.
Today, only 6% of workers have prescription plans with such free choice, reports the Kaiser Family Foundation, which conducts an annual survey of employer health benefits. Kaiser's survey shows that more insurers are making more distinctions among medicines for which they will help pay and, in most cases, asking workers to shoulder a higher proportion of costs for drugs that cost more.
Most patients welcome generics enthusiastically. Retail giants such as Wal-Mart and Target have begun filling most generic prescriptions for prices as low as $4 apiece. Generic drugs cost between 30% and 80% of the brand names they mimic, and price tags on those pioneer medicines are headed upward. Wholesale prices for the top-selling 50 brand-name medications rose by about 8% in 2007, according to a report by Delta Marketing Dynamics, which tracks drug trends. That's after hikes of about 7% in 2006 and about 6% in 2005.
At the same time, Medicare, Medicaid, private insurance companies and hospital pharmacies are trying to hold down rising costs by aggressively encouraging patients to use generics. Increasingly, many are going further: They are asking patients to switch to a different class of drugs to treat a condition -- say, from an ACE inhibitor to a beta blocker to control high blood pressure -- because more generics may be available in one drug class than another. Such "formulary switches" can be more problematic than a brand-to-generic switch, because the old and new drugs work differently.
As generics move into Americans' medicine chests in growing numbers, two things are likely, say experts: There will be copycat medications that work differently -- and sometimes less effectively -- than originals; and there will be patients who do not respond as well to them. Patients and doctors should be alert to variations in a new prescription's effectiveness, they advise, and report their concerns to the FDA's adverse-events monitoring system, called MedWatch ( www.fda.gov/medwatch).
"The generics industry is highly successful, and it wouldn't be if it was always failing patients," said R. William Soller, a professor of pharmacology at UC San Francisco. But, he added, "it's pretty hard to think you have an absolutely perfect system."
In recent years, the system by which generic prescription drugs are approved as "bioequivalent" to their brand-name counterparts has come in for criticism from many quarters. FDA's regulation of generics is most vulnerable to criticism in cases where a medicine must be administered in very precise doses and on a precise schedule to be safe and effective. These drugs have what pharmacologists call a "narrow therapeutic index": There's a fine line between a dose that's ineffective and one that could be dangerous.
Typically, a patient's response to such medicine must be carefully monitored, and the consequences of failure could be dire: a seizure, dangerously erratic heartbeat, soaring blood pressure, blood clots or uncontrolled bleeding.
But FDA regulators have been "very categorical" in their insistence that no differences exist between generics and the pioneer drugs they follow, said Kowey. As a result, the agency has resisted studies that might call that into question with any single class of drugs, fearing that consumers will come to question the equal effectiveness of all generics. "They don't want to open the Pandora's box," said Kowey.
Dr. Gary Buehler, director of the FDA's office of generic drugs, declined an interview request. But FDA spokeswoman Sandy Walsh told The Times the "FDA cannot offer any examples where generics have been shown to not perform as expected."
The "FDA has many years of experience in the review of generic drugs and has great confidence in the quality and equivalence of generic drug products," added Walsh.