Me-Too
Drugs:
Valuable or Copycat?
(Washington DC, 7/11/02): A new report reveals that 65 percent of drugs approved
in the last decade are modified mimics of existing medications, or "me-too"
drugs. However, experts warn women against hastily dismissing these copycats
as insignificant to their health. After all, studies show that one size does
not fit all when it comes to medicine. The effectiveness of a drug and the frequency
and intensity of associated adverse reactions have all been shown to vary with
gender, race, genetics, age and other factors.
"While some me-too drugs may provide little benefit over their predecessors,
others give women much needed choices," said Sherry Marts, PhD, scientific
director of the Society for Women's Health Research in Washington, DC.
Some Me-Too Drugs Worth the Wait
Critics caution that "knock-offs" of existing drugs contribute to
rising costs and play a role in limiting access to generics by extending patent
protection while offering little benefit to patients. Yet these "me-too" drugs
differ from their predecessors in a number of important ways. Some are combined
with other active ingredients, some offer a different dose, and others differ
in their delivery method (i.e. oral, injection and patch). While this tweaking
does not constitute a medical breakthrough, it may result in changes in metabolism
that can lead to differences in drug effectiveness and side effects that vary
from individual to individual.
A new drug, although similar to one already on the market, still may provide
some patients with significant clinical benefits. Take, for example, antidepressants.
Serotonin reuptake inhibitors (SSRIs) like Prozac are popular with physicians
and patients for the treatment of depression. Members of this class of drugs
work by increasing levels of serotonin, a chemical messenger in the brain. However,
different SSRIs have different effects on mood and important side effects, such
as changes in libido or weight gain. An SSRI that works well and with tolerable
side effects in one person may cause unpleasant effects or be less effective
in another. If there were only one SSRI available, many people with depression
would be denied effective, tolerable medication, explained Marts.
Birth control pills also illustrate the importance of incremental improvements
in drug development. Today, the active ingredients in oral contraceptives are
little different from those introduced four decades ago. Yet evolving doses,
types and combinations of hormones in newer birth control pills offer modern
women excellent protection against pregnancy with fewer of the risks associated
with outdated versions of the drug. Older forms of the pill containing higher
doses of hormones are associated with a higher risk of blood clots and stroke
compared with new lower dose pills. Furthermore, nausea and other more benign
side effects are less frequent with more modern formulations.
"If it weren't for me-too drugs, women would still be taking high-dose
birth control pills with their high risk of dangerous and uncomfortable side
effects," said Marts.
Similar drugs may provide different levels of effectiveness or different side
effects for a number of reasons. Drugs that have the same mechanism of action
may, due to differences in their chemistry, be absorbed into the bloodstream
or broken down and excreted at different rates. A drug that is absorbed quickly
and broken down slowly may be taken less often or at a lower dose. If a me-too
drug is effective at a lower dose, it may cause fewer side effects. Different
delivery methods can accommodate a range of patient preferences. A choice of
similar-acting drugs can allow physicians to prescribe drugs together with less
risk of interaction.
Making the Right Choice
The best drug choice will vary from person to person. So what is a woman to
do when making a decision about medication?
- Educate yourself about your medical condition and all
available medications.
- Before taking a new drug, discuss all benefits and
risks with your doctor and pharmacist.
- Ask if there are older, cheaper and equally effective
alternatives. For patients who do not respond to the alternatives, potential
health benefits of newer versions may outweigh financial costs.
- Report any and all side effects to your doctor.
- Discuss with your doctor all other prescription and
over-the-counter drugs and supplements you take to minimize the risk of adverse
drug interactions.
The Society for Women's
Health Research is the nation's only not-for-profit organization
whose sole mission is to improve the health of women through research. Founded
in 1990, the Society brought to national attention the need for the appropriate
inclusion of women in major medical research studies and the resulting need
for more information about conditions affecting women. The Society advocates
increased funding for research on women's health, encourages the study of sex
differences that may affect the prevention, diagnosis and treatment of disease,
and promotes the inclusion of women in medical research studies. Dr. Donnica
Moore has been a member of the Society since 1990 and is a past member of its
Board of Directors.
For more information on clinical research, click here.
Created: 7/11/2002 - Donnica Moore, M.D.
