Pristiq's FDA Chances: Depression – Yea; Menopause – Nay

As more info on Pristiq continues to roll out, I'll do my best to track them quite closely.

While Wyeth scrambles to resolve issues in its Puerto Rico plant to meet FDA standards, Ms. Kathleen Kerr of Newsday recently reported on Pristiq's potential to be approved for use in depression and hot flashes resulting from menopause. I was so excited to see some decent reporting on a mental health issue in a paper other than the NYT. It was also nice to see that it didn't end with "Shares of Wyeth fell 38 cents Friday to close at $51.50 on the New York Stock Exchange."

"If Pristiq wins Food and Drug Administration approval, it will be the first antidepressant and only non-hormonal remedy marketed specifically for hot flashes. But Pristiq isn't without problems – it poses rare suicide risks in young people."

I've scoured the Internet and have found scant information regarding
Wyeth's clinical trials on Pristiq (generic name: desvenlafaxine).
Please e-mail me if
there's specific information regarding the "rare suicide risks" posed
in those under 18. (I can only assume that this statement comes from
the general black-box warning assigned all antidepressants .)

Wyeth, according to the Newsday article, is still in the middle of clinical trials. (From what I can see, they are in Phase III.)
Wyeth currently is testing the drug at 50 mg for effectiveness. About
half of the patients in the clinical trial felt nauseous in doses
higher than 100 mg. The highest dosage that I know of is 400 mg.

"It turns out anti-depressants like Effexor XR (venlafaxine), another
Wyeth drug already on the market for depression, can somewhat control
hot flashes, and some doctors already prescribe it for that purpose.
Doctors may prescribe drugs approved for one ailment for others – a
practice called off-label use."

So doctors already prescribe Effexor for off-label use. This means one
of two things: Wyeth has sales reps pushing Effexor for off-label usage
regarding hot flashes in menopause (vasomotor symptoms, I presume) or
doctors are reporting that Effexor helps their patients who suffer from
these menopausal symptoms. I'd hate to think it's the former.
Especially not with what has gone down with Eli Lilly and Zyprexa. But
do many of the patients using Zyprexa really know where their side
effects are coming from? I digress…

"Pristiq is not chemically identical to Effexor XR but does contain its active metabolite, O-desmethylvenlafaxine."

OK – not chemically identical. Just, uh, similar. Venlafaxine
hydrochloride, desvenlafaxine succinate. Please note: desvenlafaxine
succinate also operates under the clinical trial name DVS-233. Nice to
have handy when the generic name isn't used in clin. trial results.
(I've noticed.)

"'They [Pristiq and Effexor] have some of the same ingredients,' Wyeth spokeswoman Gwen Fisher said. 'The FDA has deemed it a separate drug and required separate clinical trials.'"

Ms. Gwen Fisher, bless her heart, is innocently (term used loosely) defending Pristiq's individuality, we shall say. "Pristiq does not equal Effexor." Since Pristiq's molecules are structured somewhat differently, the FDA requires new trials and data for the drug to be approved for its intended use. I love the following paragraph:

"To retain sales, pharmaceutical companies often develop new drugs that
mimic older ones facing loss of patent protection. The idea is to keep
customers who might otherwise switch to new generic drugs."

It gets better, of course:

"Financial analyst Dr. Jon LeCroy of Manhattan's Natexis Bleichroeder investment bank says if Pristiq is approved, Wyeth could be looking at another blockbuster, but he doesn't expect its sales to rival Effexor's. LeCroy said Pristiq will probably have more success treating depression than hot flashes.

The problem with Pristiq has been its high level of nausea,' LeCroy
said, noting other side effects like sweating and jitteriness. 'The big
market here is as an antidepressant.'"

I can already hear Pristiq's cha-chings not rivaling those of Effexor's. Dr. LeCroy's theory would mean that Pristiq won't be the Godsend that Wyeth hopes it to be if the menopausal market isn't safely in their corner.

Here's the thing: Wyeth's marketing strategy for Pristiq is to hail it as the "new" antidepressant drug, which can also serve as medicine that staves off vasomotor symptoms. Once Effexor goes generic, chances are that Wyeth will not be able to retain most of the consumers they had on Effexor. Doctors will be hesitant to prescribe Pristiq, at first, until more data comes out about its efficacy. Drug reps will convince doctors that,  "Hey! Pristiq is no different than Effexor! It's just structured differently." Not only that, the reps can point out, "Look – Effexor was prescribed off-label by doctors for hot flashes. Pristiq is much better for that, FDA-approved, and specifically targets those menopausal symptoms." If Pristiq is somehow FDA-approved with the data of low-dosage trials, doctors may avoid prescribing the med because of overwhelming evidence pointing to nausea at higher doses. What menopausal woman needs nausea with hot flashes? Ugh.

Imagine this scenario: A patient with – heck – or without healthcare needing antidepressant medication. The patient with healthcare may be denied coverage of Pristiq because its generic, venlafaxine by this point, is cheaper. (Something like this happened to me with Paxil a few years ago.) A patient without healthcare wants the cheapest generic antidepressant that the doctor prescribes. Enter venlafaxine once again. Wyeth's market share immediately plummets for all quarters of 2010.

"Some physicians are not so sure Effexor provides relief for hot flashes and they wonder whether Pristiq really can.

Dr. Benjamin Goldman, an associate attending physician in obstetrics and gynecology at North Shore University Hospital in Manhasset, says he has prescribed Effexor for menopausal mood swings and anxiety but not for hot flashes.

'I wouldn't tell you off the bat it was good for hot flashes," Goldman said. "I really don't have patients that say Effexor helps with vasomotor symptoms.'"

It'd be interesting if the majority of attending physicians feel the same way. Ms. Kerr was a smart cookie and grabbed a rebuttal from spokeswoman Fisher.

"Fisher of Wyeth says the company has done 'really thorough trials for women for vasomotor symptoms [like hot flashes].'"

Nice quote to give, Fisher. The FDA will give its nay or yea in April. It wouldn't surprise me if they said yea to antidepressant use and nay to vasomotor use because of lack of evidence in improved symptoms. Clinical trials send to last somewhere between 6-12 weeks so it would still remain to be seen whether Pristiq would drop off for long-term use.

And lastly:

"Dr. Eric Hollander, chairman of the psychiatry department at Manhattan's Mount Sinai School of Medicine, cautions that antidepressants like Effexor can, on occasion, switch people who are bipolar into manic episodes.

'You want to screen [patients] for bipolar disorder," Hollander said. "They need to be aware of side effects.'"

Dammit. Thank you, Dr. Whoever-You-Are at my behavioral hospital for diagnosing me properly. [sarcasm]

11 thoughts on “Pristiq's FDA Chances: Depression – Yea; Menopause – Nay

  1. I have just completed my first two weeks on Pristiq. I have suffered from MDD for 35 years. I cannot take Effexor because it increases my appetite. Pristiq has really helped me. I have taken everything and I think I have finally found something that works for me. Don’t dismiss this drug because it is an Effexor metabolite.

  2. All I see in this post is hatred of the drug companies. I hate em too, but I’m stuck needing their drugs. I don’t care what it’s called, or how they market it, as long as it helps me out of my pit of despair. truly. If you don’t feel this way, you probably don’t have depression.

  3. I have been taking Pristiq for about ten days now, after taking Effexor for the last 8 years. I am not totally sure it is going to help me with the depression as well as the Effexor, but my blood pressure is down between 30 and 40 points. I cut my blood pressure medication in half today. This evening my blood pressure was 105/64. My heart rate is down too. It has been hovering around 100, but is now between 70 and 80.
    To be on the fair side, I think the Effexor is what caused my blood pressure to go up.
    If I can get relief from depression without all the side effects, then I don’t care what all you are saying about the drug companies and their label,off label deal. I just want to feel better.

  4. I have been on Zoloft for over a year now with continued depression. I have just taken my first dose of Pristiq. What i am looking for is answers to what possible side effects i could experience from this drug.

  5. Jim,
    It seems the worst that people experience at the current time is nausea. An excerpt from the prescribing information:
    The most commonly observed adverse reactions in Pristiq-treated MDD patients in short-term
    fixed-dose studies (incidence ≥ 5% and at least twice the rate of placebo in the 50 or 100 mg
    dose groups) were: nausea, dizziness, insomnia, hyperhidrosis, constipation, somnolence,
    decreased appetite, anxiety, and specific male sexual function disorders.

    Read more in the PI PDF under section 6.1 to learn more about the possible side effects.

  6. I took pristiq for 3 days and the first side effect I had was itchy head, than I got numbness and tingling in the whole upper half of my body and it felt like my blood was on fire. I could not eat for a month and I still have symptoms and it has been a whole month I also had pyralisis and severe pain in my arms. This is the worst drug I have ever had in my life.I dont suggest taking any other drugs with this like blood pressure meds, coumidin , and dont anyone ever stop this med you have to taper off of this. If you have these side affects tell your doc right away the fda is well aware of these side affects. I have not been able to work because of this.

  7. also more side effecfs is vomiting, diahrea, nausea, loss of appitite, rapid weight loss, horrible gory dreams, loss of sleep, not being able to concentrate, weakness, these are severe symptoms. And the reaction lasts for a very long time.

  8. My name is Judith Haven and i would like to show you my personal experience with Effexor.
    I am 37 years old. Have been on Effexor for at least 1 years now. As soon as I was on the beginning dose I could feel releave from my anxiety. My family life is so much better. My kids notice it. They applaud my for taking the side affects for a better live with them. No explosive episode any more.
    I have experienced some of these side effects-
    Nightsweats, I have twitches if I forget a dose.
    I hope this information will be useful to others,
    Judith Haven

  9. I was on effexor for two tears,was working well,then started the bruising.I remember counting them once,legs alone,around 50. I also had night sweats,weight loss,and bit in my sleep(once,and that was the final straw).Went on Prozac-made me tired and fat.Thinking of Prisiq,is it the new effexor?

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