Warning: A new twist on fen-phen being prescribed as diet cocktail drug despite FDA concerns
AndyJo and DeeLeigh alerted me to this story appearing in today's New York Times:
Some of you might have heard about the combination drug talked about in this article, phentermine and topiramate. Phentermine, if you remember, was the phen half of fen-phen. That's not to impugn phentermine by association, since the major side effects of fen-phen were seen to be caused by fenfluramine half.
However, make no mistake about it -- phentermine is a stimulant, that acts to suppress appetite much in the same way as ephedra does (phentermine is a congener of amphetamine). It's speed, and carries a similar range of side effects as other amphetamines like palpitations, dizziness, heart valve damage.
Topiramate (Topomax) side effects vary, mainly neurological (like dizziness, and pins-and-needles). There have been some cases of severe ocular side effects like glaucoma.
As for how effective the topa-phen combination is, I'm having a hard time finding long-term studies that aren't paywalled. There was one at 6 months (hardly useful); another at one year -- funded by Vivus, the makers of Qnexa (also hardly useful/reliable), another at two years -- again, funded by Vivus.
Additionally, from what I'm scraping up from the studies I can actually read, the weight loss effects of topiramate may in fact be temporary. This one study, conducted on children, says that weight was regained after tolerance was achieved at about 12 - 18 months.
The NYT article itself uses the problematic language one comes to expect in weight-related articles, like the euphemistic and largely meaningless term "obesity doctor" for a person who is in fact trying to reduce the incidence of obese people (recall, 'obesity' is not a disease). It's like a women's doctor whose mission is to reduce the number of women, or a pediatrician whose mission is to reduce the number of children. Definitions and language is important -- propaganda and redefinition of terms is the grease of the wheels of a moral panic.
The most important thing to take away from the article, and from this post, is that regardless of whether the topa-phen combination is 'effective' according to whatever the arbitrary standards of the FDA regarding weight loss drugs is today or tomorrow or ten years from now, phentermine is only approved for short-term use. Phentermine is an appetite suppressant. As soon as phentermine is not taken any more the individual will eat normally and gain back most if not all the lost weight.
Starvation is not a 'treatment' for fatness, especially not short-term starvation. The only long-term 'treatment' that seems to work is daily privation and semi-starvation -- an activity that will consume as much time as a part-time job -- for the rest of one's natural life. In short, the life of an ascetic. Which is a fine choice if that's what you want. But to expect that all fat people should live as ascetics is monstrous.
What I'm most concerned with is the stamp of "FDA approval" being used as a proxy for a treatment's effectiveness or long-term safety. Basically these treatments are designed to meet the approval minimums for the minimum necessary length of time. Doctors and patients are fooled into believing something is effective because it has that FDA approval stamp -- but how often as a patient did your doctor mention your weight loss drug was only effective or safe in 1- to 2-year trials, or that it hasn't been tested in the long term at all, or after the year you take it and lose some weight you can no longer take it anymore?
Even in the article we have this story:
“I can’t tell you how many people I sent to him because they saw the success I had,” said Lynn Adams, a retired teacher, referring to Dr. Thomas Najarian, the inventor of Qnexa who opened a weight-loss clinic here in 2001.
Ms. Adams said she took the two drugs for a year and lost about 80 pounds. She has taken the drugs from time to time since then but is off them now and has gained about half the weight back.
Who wants to bet that she recommended her friends jump on this new diet drug bandwagon at the peak of her weight loss and not after she gained half of it back? And how in the heck is she still being prescribed topa-phen if phentermine is only approved for short term use?
And just so we can be very clear about the responsibility for what looks to be like the next diet drug disaster, the doctors and clinicians who prescribe topa-phen are acting like mindless pharma-pushing automatons.
Doctors are just as susceptible to corruption as anyone else. A doctor who founds his career on weight loss and eliminating fat people needs dramatic success stories to promote himself, and is much more willing to throw caution to the wind if it gets him a success story and more word-of-mouth referrals.
The main danger is: weight loss happens on a curve that bottoms out over a period of months, giving an illusory 'permanent' success that is can then be paraded around to friends. A walking advertisement that, once it's served its purpose -- getting more butts into a weight-loss doc's waiting-room chairs -- regains and fades back into the shadows. We've seen that pattern with popular diet programs. Trumpet some minor celeb's loss at the bottom of the cycle and pretend it's permanent, then ignore their inevitable regain and queue up the next minor celeb to do it all over again.
My prediction is the short-term effectiveness of the topa-phen combination (6- to 12- months) will be sufficiently pushed by Vivus studies to get FDA approval for something like Qnexa. Then, as people start regaining as they tolerate topiramate and no longer can take the phentermine (which is only approved for short-term use), they will regain the weight they lost (12- to 24- months).
It will be the same old sad story, with the same old speed-related heart valve damage in addition to neurological side effects caused by the topiramate. And the population becomes less healthy, yet again, in its quest for thinness as a proxy for health.
Readers, beware the topa-phen mixture. And tell your friends.
1. L. Vijaya. "Topiramate induced secondary angle closure glaucoma." JPGM, Vol. 52, 2006.
2. P. M. Levisohn, "Safety and Tolerability of Topiramate in Children." J Child Neurol December 2000 vol. 15 no. 1 suppl S22-S26. link
3. K. M. Gadde et al. "Effects of low-dose, controlled-release, phentermine plus topiramate combination on weight and associated comorbidities in overweight and obese adults (CONQUER): a randomised, placebo-controlled, phase 3 trial" The Lancet, Volume 377, Issue 9774, Pages 1341 - 1352, 16 April 2011 study funded by Vivus, makers of Qnexa link