Abilify for Bipolar Maintenance: More Hard Questions

May 31, 2011

Much attention has been drawn to a recent PLoS Medicine article criticizing the evidence base for the use of Abilify as maintenance treatment for bipolar disorder.  The major points emphasized by most critics are, first, that the FDA approved Abilify for this purpose in 2005 on the basis of flawed and scanty evidence and, secondly, that the literature since that time has failed to point out the deficiencies in the original study.

While the above may be true, I believe these criticisms miss a more important point.  Instead of lambasting the FDA or lamenting the poor quality of clinical research, we psychiatrists need to use this as an opportunity to take a closer look at what we treat, why we treat, and how we treat.

Before elaborating, let me summarize the main points of the PLoS article.  The authors point out that FDA approval of Abilify was based on only one “maintenance” trial by Keck et al published in 2007.  The trial included only 161 patients (only 7 of whom, or 1.3% of the total 567 who started the study, were followed throughout 26 weeks of stabilization and 74 follow-up weeks of maintenance).  It also consisted of patients who had already been stabilized on Abilify; thus, it was “enriched” for patients who had already shown a good response to this drug.  Furthermore, the “placebo failures” consisted of patients who were abruptly withdrawn from Abilify and placed on placebo; their relapses might thus be attributed to the researchers’ “randomized discontinuation” design rather than the failure of placebo.  (For more commentary, including follow-up from Bristol-Myers Squibb, Abilify’s manufacturer, please see this excellent post on Pharmalot.)

These are all valid arguments.  But as I read the PLoS paper and the ongoing discussion ever since, I can’t help but think, so what??  First of all, most psychiatrists probably don’t know about the PLoS paper.  And even if they did, the major questions for me would be:  would the criticism of the Keck et al. study change the way psychiatrists practice?  Should it?

Let’s think about psychiatric illness for a moment.  Most disorders are characterized by an initial, abrupt onset or “episode.”  These acute episodes are usually treated with medications (plus or minus psychotherapy or other psychosocial interventions), often resulting in rapid symptomatic improvement—or, at the very least, stabilization of those symptoms.

One big, unanswered (and, unfortunately, under-asked) question in psychiatry is, then what?  Once a person is stabilized (which in some cases means nothing more than “he’s no longer a danger to himself or others”), what do we do?  We don’t know how long to treat patients, and there are no guidelines for when to discontinue medications.  Instead we hear the common refrain:  depression, schizophrenia, and bipolar disorder, are lifelong illnesses—”just like hypertension or diabetes”—and should be treated as such.

But is that true?  At the risk of sounding like a heretic (and, indeed, I’d be laughed out of residency if I had ever asked this question), are there some cases of bipolar disorder—or schizophrenia, or depression, for that matter—which only require brief periods of psychopharmacological treatment, or none at all?

The conventional wisdom is that, once a person is stabilized, we should just continue treatment.  And why not?  What doctor is going to take his patient off Abilify—or any other mood stabilizer or antipsychotic which has been effective in the acute phase—and risk a repeat mood episode?  None.  And if he does, would he attribute the relapse to the disease, or to withdrawal of the drug?  Probably to the disease.

For another example of what I’m talking about, consider Depakote.  Depakote has been used for decades and is regarded as a “prototypical” mood stabilizer.  Indeed, some of my patients have taken Depakote for years and have remained stable, highly functional, and without evidence of mood episodes.  But Depakote was never approved for the maintenance treatment of bipolar disorder (for a brilliant review of this, which raises some of the same issues as the current Abilify brouhaha, read this article by The Last Psychiatrist).  In fact, the one placebo-controlled study of Depakote for maintenance treatment of bipolar disorder showed that it’s no better than placebo.  So why do doctors use it? Because it works (in the acute phase.)  Why do patients take it?  Again, because it works—oh, and their doctors tell them to continue taking it.  As the old saying goes, “if it ain’t broke, don’t fix it.”

However, what if it is broke[n]?  Some patients indeed fail Depakote monotherapy and require additional “adjunctive” medication (which, BTW, has provided another lucrative market for the atypical antipsychotics).  In such cases, most psychiatrists conclude that the patient’s disease is worsening and they add the second agent.  Might it be, however, that after the patient’s initial “response” to Depakote, the medication wasn’t doing anything at all?

To be sure, the Abilify study may have been more convincing if it was larger, followed patients for a longer time, and had a dedicated placebo arm consisting of patients who had not been on Abilify in the initial stage.  But I maintain that, regardless of the outcome of such an “improved” trial, most doctors would still use Abilify for maintenance treatment anyway, and convince themselves that it works—even if the medication is doing absolutely nothing to the underlying biology of the disease.

The bottom line is that it’s easy to criticize the FDA for approving a drug on the basis of a single, flawed study.  It’s also easy to criticize a pharmaceutical company for cutting corners and providing “flawed” data for FDA review.  But when it comes down to it, the real criticism should be directed at a field of medicine which endorses the “biological” treatment of a disorder (or group of disorders) whose biochemical basis and natural history are not fully understood, which creates post hoc explanations of its successes and failures based on that lack of understanding, and which is unwilling to look itself in the mirror and ask if it can do better.


Nuedexta: “Pipeline in a Pill” or Pipe Dream?

April 18, 2011

If you’re like me, you’ve probably seen numerous Internet ads for a new medication called Nuedexta from Avanir Pharmaceuticals.  Nuedexta was approved in October 2010 for the treatment of “pseudobulbar affect,” or PBA.  My first reaction was one of surprise, as PBA is relatively uncommon, or so I was taught: why would a drug company be aggressively advertising a drug with such a niche market?  However, as I thought about the symptoms that define PBA—and then, last week, I received a Nuedexta promotional packet in the mail—I figured I should take a look “under the hood.”

First of all, I reviewed the presentation and biology of PBA.  I remember being taught in residency that it is a fairly uncommon manifestation of neurological illness, although it has a very distinctive presentation, namely, emotional expressions that are disconnected from any subjective emotional changes.  Indeed, an alternate name for it is “pathological laughing and crying.”  Certainly, the discrepancy between a patient’s emotional display—which may be extreme, and cause great distress to caregivers—and the lack of any subjective change in mood, is highly suggestive of a focal brain abnormality.

PBA is typically caused by a specific brain lesion between the cortex (the source of voluntary thought/action) and the brainstem (the source of involuntary emotional expression like laughing and crying).  Normally, we’re stimulated to laugh or cry by something funny or sad; these emotions are first processed in the cortex, which then sends a message to the brainstem to express that emotion.  If you have a lesion between your cortex and brainstem (e.g., from a stroke, multiple sclerosis, or a degenerative process) then the emotional expression can be entirely separated from the conscious awareness of it.

Over the last decade some research groups have begun to look at dextromethorphan as a potential treatment for PBA.  Dextromethorphan, also known as DXM, is a cough suppressant, the active ingredient in Robitussin, not to mention a drug often used recreationally for its dissociative and hallucinogenic properties.  Dextromethorphan is an NMDA antagonist (i.e., it prevents glutamate from activating target cells via NMDA receptors) as well as an agonist of a type of receptor called “sigma-1,” whose role is much less understood.

When dextromethorphan is combined with quinidine, another widely available drug (used to treat heart arrhythmias), the quinidine inhibits dextromethorphan’s metabolism, allowing it to penetrate the brain at doses low enough to avoid any peripheral toxicity.  Once inside the brain, it “may act on regions implicated in emotional expression” (by an unknown mechanism) and, indeed, it improves PBA symptoms with the only significant side effects being dizziness and diarrhea.  The new drug Nuedexta is a combination of 20 mg dextromethorphan and 10 mg quinidine, and the estimated cost will be from $3000-$5000 per year.

(BTW, note the theme here, which is similar to what I wrote about with Contrave:  Nuedexta is actually a combination of two existing, generic—i.e., cheap—drugs, with a significant markup, to cover the costs of clinical testing, marketing, and, of course, shareholder profits.)

Physicians—and patients—may wonder why we need a new drug to treat PBA.  Certainly, this is a good question (although I think PBA is simply Avanir’s “foot in the door,” as I’ll discuss below).  A 2007 review in the Annals of Neurology shows that a number of medications, including SSRIs like citalopram, and tricyclic antidepressants (TCAs), are effective in managing the symptoms of PBA (see also here).  And, as I mentioned earlier, the proper diagnosis of PBA requires the presence of an underlying neurological disorder, and treatment of the disorder, too, may ameliorate the PBA symptoms.

Interestingly, while I searched for literature references discussing PBA, I found that most—if not all—of the literature from the last 5-6 years has been funded or underwritten by Avanir Pharmaceuticals—and all of which discussed the benefits of dextromethorphan/quinidine.  This included an “educational review” published by the National Stroke Association in 2005.  In fact, the editors of the Annals of Neurology issue I cited above tried to get someone to write a review on PBA but couldn’t find any authors “untouched by Avanir.”  It certainly seems that Avanir’s PR effort has paid off.

The coup de grâce, in my opinion, is an “expert review” on PBA published in the journal CNS Spectrums in October 2005.  It’s a roundtable discussion on how to distinguish PBA from other psychiatric and neurologic disorders—and, of course, the benefits of dextromethorphan/quinidine.  It seems like a fair review, although the authors make comments that broaden the definition of PBA to include other disturbances of affect, which are extremely common among psychiatric patients. “It may be useful to regard affective lability,” they write, “as a disorder of affect that exists at a point on a continuum between normal affective variability and the more severe end of the continuum characterized by [PBA].”  Furthermore, they encourage clinicians to “include a specific assessment for PBA” in all patients with any neurological condition, to prevent their being “misdiagnosed” with a psychiatric disorder—the implication being that what we might call “poststroke depression” might actually be PBA.  And they even open the door to the possibility that “PBA-like” symptoms might not have a recognizable neurological basis:  “In some cases PBA may be the only clinically identifiable manifestation of the neurological condition.  In light of the overlap between the neurology of affect regulation and the neurology of psychiatric conditions, … PBA may sometimes occur in the latter context as well.” [Emphasis mine.]

You can see where this is all headed—and probably why I received a promotional packet for Nuedexta, even though I’m not a neurologist.  Here we have a new medication, which has been approved for a neurological syndrome whose major manifestation is “affective instability.”  Even though the proper diagnosis of PBA requires far more than that, clinicians will undoubtedly use it off-label for the affective lability seen in many other conditions (such as bipolar disorder, schizophrenia, autism, dementia, maybe even childhood irritability, etc).  And my bet is that Avanir will try to get Nuedexta approved for all of these conditions.

(BTW, Nuedexta has never been compared head-to-head with SSRIs or TCAs, and the trials which led to Nuedexta’s approval showed only slight improvement vs. placebo in patients with PBA due to multiple sclerosis and ALS.)

Indeed, Avanir’s investor materials (see pdf here) already state that the company will seek approval for multiple sclerosis-related pain, and for behavioral symptoms in dementia.  And when one considers how atypical antipsychotics have been affected by “indication creep,” it is probably only a matter of time before Nuedexta will be tested for other disorders characterized by affective changes, including the big kahunas: depression and bipolar disorder.  To that end, during a November 2009 conference call to shareholders, Keith Katkin, Avanir’s CEO, described Nuedexta as a “pipeline in a pill.”

I should note here that I have not tried Nuedexta so I can’t say whether it is effective.  I also have no financial interest in Avanir Pharmaceuticals.  I don’t see how Nuedexta’s pharmacological properties might control affective outbursts (but then again, I can’t explain precisely how SSRIs treat depression, either).  Certainly I’ve read of isolated cases in which Nuedexta has led to “dramatic improvement,” but those cases are from spokespeople with “skin in the game,” so to speak.  Nuedexta might be a blockbuster drug in neurology and psychiatry alike, and I’m willing to give it that chance.  However, at this stage the marketing speaks far louder than the data, and the seeds are already being sown for the more widespread use of this relatively unproven agent.  We need to be cautious not to be swayed by the influence of those who want to make a few bucks (or a few billion) off our ignorance.


Off-Label Meds: Caveat Prescriptor

March 13, 2011

In medicine we say that a drug is “indicated” for a given disorder when it has gone through rigorous testing for that condition. Typically, a drug company will perform clinical trials in which they select patients with the condition, give them the new drug, and compare them with similar patients who are given a placebo (or an established drug which is already used to treat the disease). In the US, when the FDA approves a drug, the drug company is then permitted to advertise it in magazines, journals, TV, the internet, and directly to doctors, but they must specify its “approved” use.

In the past few years, several drug companies have found themselves in trouble after accusations of marketing their drugs for off-label indications. Total fines have reached into the billions, and many companies have vowed to change their marketing practices in response.

It should be emphasized, however, that doctors use drugs off-label very frequently. This is particularly true in psychiatry, where an estimated 31% of all prescriptions are off-label. Some familiar examples include trazodone (an antidepressant) for insomnia or beta blockers (originally approved for hypertension and heart failure) for anxiety. Furthermore, some very common symptoms and conditions, such as personality disorders, impulsivity, nightmares, eating disorders, and PTSD, have no (or few) “indicated” medications, and yet we often treat them with medications, sometimes with great success. And since the FDA restricts its approvals to medications and devices, even psychotherapy—something we routinely recommend and “prescribe” to patients—is, technically, off-label.

One colleague took this one step further and explained that virtually any psychiatric drug which has been prescribed for more than 8 or 12 weeks is being used “off-label” since the studies to obtain FDA approval are generally no longer than that. Admittedly, that’s nitpicking, but it does demonstrate how the FDA approval process works with a very limited amount of clinical data.

Drug companies that deliberately market their drugs for off-label indications are indeed guilty of misrepresenting their products and deceiving doctors and consumers. But to blame them for bad patient outcomes conveniently ignores the one missing link in the process: the doctor who decided to prescribe the drug in the first place. Whether we like it or not, drug companies are businesses, they sell products, and as with everything else in our consumerist society, the buyer (in this case the doctor) must beware.

Here’s an example. A new drug came to market in February called Latuda, which has been FDA approved for the treatment of schizophrenia. Before a few months ago, most community psychiatrists (like me) knew absolutely nothing about this drug.

If a sales rep visits my office tomorrow and tells me that it’s approved for schizophrenia and for bipolar disorder, she is obviously giving me false information. This is not good. But how I choose to use the drug is up to me. It’s my responsibility—and my duty, frankly—to look at the data for schizophrenia (which exists, and which is available on the Latuda web site and in a few articles in the literature). If I look for data on bipolar disorder, I’ll find that it doesn’t exist.

That’s just due diligence. After reviewing the data, I may conclude that Latuda looks like a lousy drug for schizophrenia (I’ll save those comments for later). However, I might find that it may have some benefit in bipolar disorder, maybe on particular symptoms or in a certain subgroup of patients. Or, I might find some completely unrelated condition in which it might be effective. If so, I should be able to go ahead and use it—assuming I’ve exhausted the established, accepted, and less costly treatments already. Convincing my patient’s insurance company to pay for it would be another story… but I digress.

I don’t mean to imply that marketing has no place in medicine and that all decisions should be made by the physician with the “purity” of data alone. In fact, for a new drug like Latuda, sales reps and advertising materials are effective vehicles for disseminating information to physicians, and most of the time it is done responsibly. I just think doctors need to evaluate the messages more critically (isn’t that something we all learned to do in med school?). Fortunately, most sales reps are willing to engage doctors in that dialogue and help us to obtain hard data if we request it.

The bottom line is this: psychiatric disorders are complicated entities, and medications may have potential far beyond their “approved” indications. While I agree that pharmaceutical marketing should stick to proven data and not anecdotal evidence or hearsay, doctors should be permitted to use drugs in the ways they see fit, regardless of marketing. But—and this is critical—doctors have a responsibility to evaluate the data for both unapproved and approved indications, and should be able to defend their treatment decisions. Pleading ignorance, or crying “the rep told me so,” is just thoughtless medicine.


Are Your Thoughts Still Racing, Jiefang?

March 10, 2011

A recent Vanity Fair article described the trend by American pharmaceutical companies to conduct more clinical trials outside of the United States and Western Europe.  The writer and bioethicist Carl Elliott also detailed this trend in his book White Coat, Black Hat, and it has recently received increasing scrutiny in the media.  While much attention has focused on the ethical concerns of overseas clinical trials, I’m avoiding that hot topic for now and arguing that we should pay some attention to questions of clinical relevance.

This is no small matter.  The VF article reports that one-third of clinical trials by the 20 largest US-based pharmaceutical companies are conducted exclusively at foreign sites, and medications destined for use in the U.S. have been tested in almost 60,000 clinical trials in 173 countries since 2000.  The reasons for “outsourcing” clinical trials are not surprising:  cheaper costs, less restrictive regulations, more accessible subjects, and patients who are less likely to have taken other medications in the past, thus yielding a more “pure” population and, hopefully, more useful data.

At first glance, overseas clinical trials really shouldn’t be much of a problem.  The underlying biology of a disease should have nothing to do with where the diseased person lives.  Hypertension and hepatitis are probably quite similar, if not identical, whether the patient is in Boston or Bangalore.  An article in this month’s Archives of General Psychiatry appears to reinforce this concept, showing that rates of bipolar disorder—as well as its “severity” and “impact”—are similar in a variety of different international settings.  Hence, if you were to ask me where I’d do a clinical trial for a new bipolar medication, I’d probably go where it would cost less to do so (i.e., overseas), too.

But is this appropriate?  Just because we can find “bipolar disorder” in the U.S. and in Uganda, does this mean we should we treat it the same way?  Over at the blog 1boringoldman, Mickey has uncovered data showing that trials of Seroquel (an atypical antipsychotic) for bipolar depression are being conducted in 11 Chinese provinces.  You can search the data yourself at clinicaltrials.gov (a truly fantastic tool, BTW) and find that many other psychiatric drugs are being tested worldwide, for a wide range of indications.

To a lowly community psychiatrist like me, this raises a few red flags.  As I learned in my transcultural psychiatry lectures in med school and residency, the manifestations of disease—and the recommended treatment approaches—can vary dramatically based on the culture in which the disease appears.  Even in my own practice, “bipolar disorder” varies greatly from person to person:  a bipolar patient from a wealthy San Francisco suburb experiences her disease very differently from the patient from the poverty-stricken neighborhoods of East Oakland.  A good psychiatrist must respect these differences.  Or so I was taught.

In his book Crazy Like Us, author Ethan Watters gives numerous examples of this phenomenon on a much larger scale.  He argues that the cultural dimensions that frame a disease have a profound impact on how a patient experiences and interprets his or her symptoms.  He also describes how patients’ expectations of treatments (drugs, “talk” therapy) differ from culture to culture, and can determine the success or failure of a treatment.

Let’s say you asked me to treat Jiefang, a young peasant woman with bipolar disorder from Guangdong Province.  Before doing so, I would want to read up on her community’s attitudes towards mental illness (and try to understand what “bipolar disorder” itself means in her community, if anything), learn about the belief systems in place regarding her signs and symptoms, and understand her goals for treatment.  Before prescribing Seroquel (or any other drug, for that matter), I’d like to know how she feels about using a chemical substance which might affect her feelings, emotions, and behavior.  I imagine it would take me a while before Jiefang and I felt comfortable proceeding with this approach.

There’s just something fishy about scientists from a multinational Contract Research Organization hired by Astra-Zeneca, flying into Guangdong with their white coats and clipboards, recruiting a bunch of folks with (western-defined) bipolar disorder just like Jiefang, giving them various doses of Seroquel, measuring their responses to bipolar rating scales (developed by westerners, of course), and submitting those data for FDA approval.

I sure hope I’m oversimplifying things.  Then again, maybe not.  When the next me-too drug is “FDA approved” for schizophrenia or bipolar depression (or, gasp, fibromyalgia), how can I be sure that it was tested on patients like the ones in my practice?  Or even tested at all on patients who know what those diagnoses even mean?   There’s no way to tell anymore.

The “pathoplastic” features of disease—what Watters calls the “coloring and content”—make psychiatry fascinating.  But they’re often more than just details; they include the ways in which patients are influenced by public beliefs and cultural ideas, the forces to which they attribute their symptoms, and the faith (or lack thereof) they put into medications.  These factors must be considered in any attempt to define and treat mental illness.

Clinical trials have never resembled the “real world.”  But designing clinical trials that resemble our target patients even less—simply for the sake of bringing  a drug to market quickly and more cheaply—is not just unreal, but deceptive and potentially dangerous.


What Does a Diet Drug Have in Common With a Swiffer?

February 8, 2011

What does the new anti-obesity drug Contrave have in common with the Swiffer?

Yes, I’m talking about that Swiffer, the cleaning tool that is essentially a dry mop with disposable dusters that attach to a dispensible handle.

When the Swiffer was first introduced, it was a revolutionary product.  And it remains a top seller for Procter & Gamble, its manufacturer.  But in reality, it’s not exactly a revolutionary idea.  In fact, my mother, in fact (an expert cleaner in her own right, much to my childhood chagrin) used to remark that she could have become a millionaire if she had marketed her own idea for a “homemade Swiffer”:  wet paper towels or dryer sheets wrapped around a broom head.  The Swiffer is one of those miracles of “good design”— an idea that is elegant in its simplicity but surprisingly effective in its application, and I’m sure it has led thousands of housewives (okay, and househusbands, too) to lament, “why didn’t I think of that?”

Enter Contrave.  What exactly is Contrave?  It’s a weight loss drug being developed by Orexigen Pharmaceuticals, Inc.  It’s not available yet, but you may have read about it in the business pages a few weeks ago, when Orexigen’s stock price (symbol: OREX) took a 72% nose dive in a single day after the FDA rejected it, recommending further study of the drug to rule out cardiac toxicity.

Like the Swiffer, Contrave is nothing terribly new; it’s a re-packaged “combination drug” consisting of two commonly used medications that psychiatrists and other doctors have been prescribing for years:  bupropion and naltrexone.  Bupropion (more commonly known as Wellbutrin or Zyban) is frequently used for the treatment of depression (and has been shown to cause some weight loss on its own).  Naltrexone (ReVia or Vivitrol) is an opiate antagonist and has been used in the treatment of alcoholism, opiate dependence, and impulse-control disorders.

In a clincial trial published last year, the combination of 360 mg bupropion (a respectable dose for depression, although not a dose most doctors would start with, right out of the gate) and either 16 or 32 mg naltrexone (a slightly lower dose than we use in alcohol dependence), was associated with an average 5.0% or 6.1% weight loss, respectively, over a one-year period (vs. 1.3% in the placebo group).  A related study, whose results were submitted for FDA approval, used similar doses and found that half of the patients taking Contrave lost >5% of their body weight.

So here we have a novel agent that shows some efficacy in a notoriously hard-to-treat condition, but which is not really a novel agent at all.  Just like the Swiffer is a “gee-whiz” product that is clever, remarkably useful, but conceptually quite simple.

But this is where (in my opinion) the similarities should end.  Very few people would blame Procter & Gamble for developing a product that fills a niche but is really an overpriced combination of some readily available (and much cheaper) materials.  Frugal consumers can pass on the Swiffer and make their own, while plenty of others are willing to pay the premium for the convenience of the name-brand product.  And I think we’d all agree that people can spend their money on household cleaning supplies in whatever way they see fit.

But in medicine things are different.  When a product receives FDA approval for a given indication (especially a disease as prevalent as obesity), it’s an automatic market; plenty of doctors will prescribe it, and insurance companies & public insurers like Medicaid will cover it.  Simultaneously, you can bet that a well-orchestrated promotional campaign will rally millions of customers to “ask their doctor” about this “brand new diet drug” they saw on TV.  And Orexigen will most certainly charge a hefty premium over the component costs of bupropion and naltrexone alone, to recover the costs of clinical trials and to return a profit to its shareholders.  To be sure, as doctors learn that Contrave is actually a combo of two cheaper drugs they can easily prescribe, they might prescribe less of it, but not before a huge market is created and exploited.

Ingenuity is a wonderful thing, especially when it’s brought to bear on problems that are notoriously difficult to solve, whether it’s the obesity epidemic or that mess on your kitchen floor.  However, when a manufacturer repackages old products under a new name and charges a hefty premium for it, we need to be aware of this, and make decisions accordingly.  While most consumers don’t mind paying an extra few bucks for the convenience of a Swiffer, we should think twice about allowing our cash-strapped medical system to shell out the billions for a “blockbuster” drug like Contrave.


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