Pristiq's side effects: Too close to Premarin and Prempro for comfort?

Back in January 2007, I’d mentioned that Wyeth was not only seeking to market Pristiq (desvenlafaxine) for depression but also for the use of vasomotor symptoms in menopausal women.

I just learned that Wyeth produces two major menopause drugs, Premarin and Prempro, that allegedly has produced hormones causing cancer in more than 5,000 women. This added up to a loss of 40 million users and $1 billion annually.

With Effexor going generic in 2 years and the introduction of Pristiq to the market, Wyeth hopes to lure some of those customers back and net an annual $2 billion. However, serious questions linger about Pristiq’s side effects in menopausal women.

Why did two women in the study group taking Pristiq have heart attacks
and three need procedures to repair clogged arteries compared with none
taking placebo? How can Wyeth assure long term safety when 604 of the
2,158 test subjects took Pristiq for only six months and 318 for a year
or more? And what about serious liver complications seen in the studies?

Martha Rosenberg, reporting on Pristiq’s use as a menopausal drug, culled comments from CafePharma’s message boards and found one thread rife with mixed comments on the new drug. From an Anonymous commenter:

As someone who is close to the Medical Affair, I hate to burst
your bubble. Pristiq is not a good drug by any standard. We tried to
get 100mg approved as the standard dose. But our patients got so sick
that they could care less about the efficacy. They just couldn’t
tolerate the drug long enough to see any improvement.

We were then forced to compromise the efficacy and tested the
50mg and hoped for the best. As far as we know, 50mg is about as
effective as 100mg XR with no additional safety or novel features. So
if you want to convert your current XR patients to Pristiq, you may not
want those who are on 150mg XR and higher or your customers will be
very disappointed.

As an extension, we consider it as a failure. Our company may
not want us know about this or to think this way as we can expect. We
can only rely on marketing now for any hope as there is nothing else we
can do on this end. Pharmacologically, we are very disappointed and it
is certainly an inferior product.

That’s a tough — for lack of a better term — pill to swallow. That’s
a bad enough assessment for a drug that’s supposed to be treatment for
depression. I can’t imagine how much worse it could be for vasomotor
symptoms. But it looks like Wyeth is just marketing Pristiq based off
of Effexor XR’s off-label usage for hot flashes in menopausal women:

FYI – doctors have been using Effexor and SSRIs for hot flashes
even before ACOG posted it on their website as an alternative to
hormone therapy during the days post WHI. They will write Pristiq for
women who have contraindications or are just afraid to take ET and HT.

Even Dr. Daniel Carlat wrote in his popular post, “Top 5 Reasons to Forget About Pristiq“:

Every patient who takes Effexor produces Pristiq in their own body, at no additional charge.

If doctors find Effexor effective in treating hot flashes, then
what’s the need for using Pristiq? Especially if Effexor’s generic will
produce similar results.

But in light of Wyeth attempting to woo the menopausal crowd back, could the side effects of Pristiq (mainly an antidepressant) follow in Premarin and Prempro’s footsteps?

Was it Wyeth’s fault that the hormone “therapy” it pushed for decades
actually increases breast cancer by 26 percent, heart attacks by 29
percent, and stroke by 41 percent, and doubles the risk of blood clots
and dementia?

But if U.S. women embrace a major psychiatric drug with possible liver
and heart complication side effects after the hormone hoax —
manufactured by the same company and at four times the cost of
Prempro/Premarin, $4 per day…

You can read the few comments on Pristiq on one of my older posts or the slew of comments on Dr. Carlat’s post pummeling Pristiq.