Wednesday, March 30, 2011

Somaxon's Silenor: A Case Study in Sleeping Pill Deception

Sometimes, despite neon warning signs and a voice in our head shouting "DON'T DO IT," we go ahead and do stupid things anyway. 

Welcome to the world of Somaxon Pharmaceuticals, unveilers of the new sleeping pill, Silenor. Billed in their press releases as "the first and only non-scheduled prescription sleep aid that is proven to provide patients with a full night's sleep, including sleep into the 7th and 8th hour," Silenor is simply a branded version of doxepin, a tricyclic antidepressant that has been available in the U.S. since the 1960s, and has long been used as a cheap sleeping pill.

A year ago, Somaxon got FDA's permission to market this me-too drug.  All they had to do was to take little pinches of generic doxepin powder, turn them into tablet form, and do some clinical trials to show it works for insomnia (see, for example, Scharf M et al, J Clin Psychiatry 2008;69(10):1557-1564). They now have an FDA indication for insomnia for the 3 mg and 6 mg doses. The lowest dose of generic doxepin in capsule form is 10 mg, so apparently the Somaxon reps will argue that this dose is too strong, and that Silenor's 3 and 6 mg forms are just right. 

A month's supply of Silenor at 3 mg or 6 mg costs $214, according to Boston area pharmacies. On the other hand, a month's supply of doxepin 10 mg costs $4 at Wal-mart. The rare patients who cannot tolerate 10 mg of doxepin can reduce the dose by opening up the capsules and mixing some of the powder in juice. Or, they can try the liquid doxepin elixir if they really need tiny doses. 

Silenor is a blatant get rich quick scheme that appears to be failing miserably. According to The Street, Silenor had total sales of only $1.4 million in the fourth quarter of 2010. At this rate, Silenor drug reps will have to ditch their cars and hike to doctors' offices with samples in their backpacks.

Shrewd analysts were predicting Silenor's early demise soon after it was approved--see for example, Douglas Krohn's June 2010 article, "The Problem With Somaxon's Silenor."  More recently, up and coming psychiatrist/blogger Steve Balt posted a great investigative piece on his Thought Broadcast blog, entitled "Thank you, Somaxon Pharmaceuticals!" Trying to be fair, Balt contacted medical affairs at Somaxon to see if they had any data showing an advantage of Silenor over 10 mg of doxepin. Interestingly, he was sent a document entitled
"Is the 10 mg Doxepin Capsule a Suitable Substitute for the Silenor® 6 mg tablet?" Apparently Somaxon was already armed and ready for me-too accusations.

Balt publishes Somaxon's chart comparing blood levels of Silenor 6 mg vs. doxepin 10 mg. At first glance, it appeared that doxepin practically overdoses patients--until Balt realized that the doxepin data was essentially made up. I won't steal any more of his thunder--please jump over to his blog for the entertaining details. 


Bernard Carroll said...

The expression pharmaceutical bottom fishing comes to mind.

SteveM said...

Re: Dr. Carroll

Dr. Carroll you got that right. The low-value me-too drug model has devolved into the no-value slap-a-new-label-on-an-old-drug model.

See also the Makena hyper-pricing gouge:

As well as the Lovaza scam:

Imagine if the Pharma companies had actually invested the marketing dollars allocated to those no value-added derivative products to R&D for new drugs instead.

Nah, Wall Street has proven that sleight of hand illusion is where the real money is. The Pharma MBA's are just playing catch up.

SteveBMD said...

Thanks for sharing my post, Dr Carlat.

I might actually be more sympathetic towards Somaxon than it appears. Let's face it: they were able to raise the money, tweak the compound (if you call subtraction "tweaking") do the trials necessary for FDA approval, and here we are talking about a "new" insomnia drug. That's progress!

Unfortunately, though, it's the Contrave fiasco all over again: existing drugs, off patent and dirt cheap, which may serve an unmed need for a brand new indication. Only big pharma (or small-cap pharma, in this case) has the time, staff, and deep pockets to run the necessary trials to show the FDA the drugs are safe and effective. It's not rocket science, but it is a lot of work, and naturally, Somaxon (and its investors) expect to be rewarded for their efforts. Notice I said "expect," not "deserve."

And there's the problem. As SteveM wrote above, our system rewards deception, clever marketing, and the fine art of niche creation. Thus, the marketing genius who sells us on 6 mg Silenor is laughing all the way to the bank, while the doc whose patients are sleeping happily (and saving $) on 10 mg doxepin goes unrecognized.

Neuroskeptic said...

So you can just take any old drug, reformulate it, and "market" it - i.e. overcharge for it, by definition - and the FDA are fine with that?

Anonymous said...

As one who suffered the taper from hell from Doxepin in spite of tapering very very slowly. I greatly pity the folks who go on this med and then have to get off it for various reasons.

One of my withdrawal problems was severe rebound insomnia. Only now am I beginning to have stability in spite of taking my last dose in June of last year.

And even then, my sleeping hours are strange which are not conducive to having a totally productive life. But considering the fact that many people have alot worse problems than me, I am not complaining.

Bernard Carroll said...

@ Neuroskeptic: To paraphrase H.L. Mencken, nobody ever went broke underestimating the venality of dodgy medical entrepreneurs.

Consider this pricing projection from Corcept Therapeutics (Alan Schatzberg’s company): they announced in 2005 that a seven-day treatment with Corlux (mifepristone) for psychotic depression is expected to run about $3,000. The comparative price of Mifeprex (mifepristone ) in gynecology at that time was $270 for a blister pack of three tablets.

Bob Marley said...

Thank you Dr. for bringing this information out to the public. I was just given samples of Silenor 6mg and I took it about an hour ago. As you can see it works real well for me. I am a diagnosed insomniac. I am really bummed that yet another medication is a joke. I will wait for something to really work...

Bob Marley said...

Thank you Dr. for bringing this information out to the public. I was just given samples of Silenor 6mg and I took it about an hour ago. As you can see it works real well for me. I am a diagnosed insomniac. I am really bummed that yet another medication is a joke. I will wait for something to really work...

Anonymous said...

I was just prescribed doxepin today and my doctor told me about the whole Silenor thing and he said he thinks it's a scam and can't believe the FDA approved this drug. If I didn't have insurance my month supply of doxepin would cost me a whole $4.33. I had a long discussion about this pharmaceutical phenomena when I picked the prescription up.