Many state governments have promoted the use of generic medicines through adoption of generic substitution and other laws. These policies are designed to ensure that a state's citizens receive the highest quality of care at the most affordable price. Consequently, increases in generic utilization have saved consumers and taxpayers billions of dollars in prescription drug costs. A recent resurgence in efforts by special interest groups to "carve out" or exempt certain therapeutic classes of medicine from generic substitution requirements (such as prior authorization and preferred drug lists), however, may significantly influence prescribing practices and spur needless increases in US health care costs.
Today, as with narrow therapeutic index (NTI) drugs in the mid-to-late 1990s, some brand manufacturers are arguing that certain classes of drugs are not safe for generic substitution. As lucrative patents expire on brand drugs, special interest groups representing brand manufacturers have renewed their efforts to maintain market share by waging misinformation campaigns throughout the country. By July 2005, over 20 states had passed legislation, and more are considering legislative proposals that would prevent the substitution of generic medicine for patients with conditions such as epilepsy, mental health disorders, and HIV/AIDS. (eg, see NC GEN. STAT. § 90-85.28, [exempting conditions such as "HIV/AIDS (and) mental illnesses" from generic substitution requirements]). A 2006 bill in Tennessee suggested that all prescribers and pharmacists "remain aware of the potential public safety and healthcare implications that generic? drug product[s] may have on persons with epilepsy." Deliberately misleading scare tactics such as this are intended to create a public perception of generic medicines as being poor-quality and unsafe substitutes for brand drugs. This could not be further from the truth.
The term NTI drug refers to a drug that could yield significantly different results when its quality or potency varies only slightly. The past controversy surrounding NTI drugs was based on the misconception promoted by some brand manufacturers that an approved generic drug could vary beyond a safe and effective range of potency of its brand counterpart and still be placed on the market.
In 1998, the FDA responded to the NTI controversy, stating that "products evaluated as therapeutically equivalent can be expected to have equivalent clinical effect whether the product is a brand name or generic drug product." True to its mission to advance public health by making medicines more affordable, the FDA has steadfastly supported its determination that a generic medicine is interchangeable with its brand counterpart. The same policy remains today.
In order to gain approval, generic drugs must undergo rigorous testing to demonstrate their equivalence to the branded counterpart. The FDA requires that a generic drug contain identical amounts of the same active ingredient as the brand name product, and that the generic drug meet the same high standards for identity, quality, and purity. The FDA has stated that its strict bioequivalence standards account for precise degrees of variation between products, so that additional testing or monitoring is unnecessary when a patient is switched from a brand to a genericin the FDA's words, "the goalposts would always be scaled to the variability of the [brand drug]." In one survey covering more than 400 samples of 24 marketed brand and generic drugs, all products were found to meet the established criteria for purity and quality. Regardless of whether the drug is prescribed for treating epilepsy, mental health disorders, HIV/AIDS, or any other medical condition, a generic substitute is equally as safe and effective as the brand drug.
It is important to note that, when a brand manufacturer alters a manufacturing process or makes changes to a formulation, it may be required to demonstrate equivalence between the new product and the old product to ensure that the drug has the same safety and effectiveness. In these instances, brand companies rely on exactly the same testing procedures as those used by generic manufacturers to demonstrate equivalence between the generic product and its brand counterpart. The FDA has stated that, if a generic drug is substituted for a brand, "the physician, pharmacist, and patient have the FDA's assurance that the physician should see the same clinical results and safety profile?any differences that could exist should be no greater than one would expect if one lot of the innovator's product was substituted for another."
In light of the FDA's long-standing policy, the recent campaigns waged by some brand manufacturers to carve out entire therapeutic classes from generic substitution laws are not only misleading, they are misguided and needless. Carve-outs will result in patients who suffer from epilepsy, mental health disorders, or whatever particular medical condition is the subject of the carve-out having less access to affordable generic medicine. More broadly, carve-outs will needlessly increase the cost of prescription drugs for consumers and taxpayers.
Pharmacists, physicians, policy makers, and patients alike should be aware of the facts about generic substitution, so that the influences of special interests are not allowed to put profits before public health.
Kathleen Jaeger, GPhA president and chief executive officer