Saturday, July 4, 2009

Salmon's Take on Schering-Plough's Asenapine, and the NYT Opinions. . . .


Earlier this week, I ran some ruminations on The New York Times article of Tuesday, and its companion opinion piece -- about recent disappointments in the pace of genomics-based therapy discoveries. Salmon, as ever, had a far more comprehensive, and thoughtful, view on these matters, in the comments. It appears below:

. . . .The results are not surprising.

First schizophrenia (skee-zo-fren-i-a not skit -zo-fren-i-ais) is most likely not a single disease we've thought of it in this manner for decades based on the symptoms. A large fraction become paranoid and withdrawn, others are happy and just laugh at everything, most have auditory hallucinations and others visual, other symptoms such as thought problems, verbal communication, and breakdown in knowing personal space can vary significantly.

As a clinician it's extremely difficult to try to figure out from external observations and discussion what even the symptoms are and what type of mental illness we are dealing with. This is particularly true for children and the changes in symptoms that occur over time.

The brain is the most complex organ in the entire body it controls thought, emotion, memory, and movement. The types of cells and the complexity of the interconnections, the intercellular biochemical actions. and what the can do is simply staggering and we essentially understand very little about how normal brains work much less diseased ones.

As for genetic causes this is not suprising. Cystic Fibrosis was the first genetic disease tackled and it was due to a defect in a single gene product a chloride transporter. Yet soon (1-2 years) after discovering the target it was apparent that there well over 1000 mutations with different degrees of effect on function from extremely severe disease resulting in death in childhood to mild illness that might otherwise not be detected but might explain a greater propensity for say respiratory infections. Plus poorly functioning chloride channels resulted in compensatory activity by other channels and that likely led to some of the problems.

The complexity of the brain makes the likelihood that schizophrenia is due to defects in multiple possible brain activities from interconnections to receptor number and binding, to intracellular downstream effects on mitochondria highly probable.

Examining the drugs that we use it's clear that they are extremely dirty and hit multiple multiple receptor targets and act in many different ways. Plus the extensive metabolism with alterations in receptor binding and effects with differences in metabolite and enantiomer exposures make it likely that you are going to have effects and side effects that you don't anticipate or understand.

On top of all this we need to remember that nature uses these same basic building blocks over and over and varies them via mutations. So it is not surprising that we have effects on the heart or the liver, or kidney's, or muscles. Or if the drugs effect mitochondria or some other target that there is cumulative toxicities that occur after years at related sites (such as the pancreas where they may cause cell death and diabetes) or on the brain itself.

Considering all this it's amazing that we have drugs that work at all. However you have to realize that a drug may work extremely well in a amall percentag of people and drive the average improvements in scores that we use to measure efficacy but in the majority work no better than placebo and in another fraction may actually make mental illness worse, (e.g. suicide, psychosis, violence). Even that idea that short term efficacy or even moderate term (6 months - 1 year) will predict long term efficacy and safety is suspect and in fact evidence from other countries tend to support this.

When you consider all this and look at how psychiatry is practiced with little to no thought or self questioning of assumptions and what happens to patients it's no wonder that patients feel victimized and many claim there are no such diseases or biological basis.

As my boss used to say when I worked in this area 'this isn't rocket science. Rocket science is easy!."

We need to listen to our patients. I was at the last psychopharmacologic drug advisory committee meeting and the patient representative was a mother whose son committed suicide and when I and other heard the story thought it was suspicious for drug induced suicide. Instead she stated that patients would rather be on the drugs and have clear thoughts and deal with the side effects. That is simply false. Many patients will accept a lower less effective dose but not a higher more effective one due to side effects. Others prefer to not take drugs at all and know that they're acting strange to others but they've made a decision and when you speak to them you realize in spite of the mental illness that it's an informed one. Instead you have families and drug companies funding campaigns to forcibly medicate people even when they're not dangerous. Plus even forcibly administering these drugs to any kid who goes into foster care or an instituion and other kids when they aren't indicated on the hypothesis that they will prevent illness when in fact with all the effects it's most likely that they will be causing problems and even death well before they might truly need an antipsychotic.

As for asenapine if it worked well I assume that it would have been approved long ago (of course there are ways to rig the system even when the studies fail and you can't tell if a drug works or not).

Thus the most likely reason for the long development, Pfizer dropping it, and the delays in approval are most likely major toxicities. Considering the major toxicities we're seeing with the structurally similar antipsychotics (Clozapine - agranulocytosis and cardiac effects, Zyprexa - cardiac effects and diabetes, Seroquel - the same) We can only surmise that the magnitude and severity of the toxicities with asenapine must be truly horrific. Of course perhaps this is why it's only submitted for short term use even though no one would ever prescribe an antipsychotic for only short term use.

Rather than hubris where Pfizer and other failed, perhaps Fred is simply doing what he has done before. Moved on before the s--- hits the fan and sold the company to someone else to deal with the mess. So I wouldn't be surprised if Merck is simply taking on another Vioxx. But this time rather than treating people at the end of life who may be able to accept the risk for themselves for a true possibility of benefit. We are instead forcibly or tricking people into medicating children without schizophrenia or clear bipolar disorder with symptoms that part of every study where response has been shown, so there is no evidence of any benefit in the majority of the children treated and clear evidence of serious harm and death. . . .

-- Salmon,
07.02.09

Indeed, Happy Fourth, one and all.

2 comments:

Anonymous said...

Thank you for the kind words.

Whenever I see my comments like this I cringe as I read all the typos, grammatical errors, and my being less than 100% clear as I just start typing.

For example when I indicate the issues with children I am referring to well documented problems with the use of antipsychotics in children in general. My fear with asenapine is that as a sublingual formulation that it will find rapid uptake in off-label use in children and especially younger children who don't swallow and in the elderly in nursing homes for dementia where administering a sublingual tablet (even if inappropriately placed on the tongue where most of the dose will be swallowed.

FDA documents from the recent advisory committee meeting indicate that even children that are in the proposed age range for the proposed antipsychotic treatments are being overdosed. Since these are based on average figures the overdosage at the lower end of the age range is likely to be much more severe and in younger patients such as those down to 5 or 6 where off label use is just as common exposures will be to even greater amounts than teenagers.

We know that some of the toxicities with atypical antipsychotics are dose and time related (diabetes, tardive dyskinesia, hormonal effects), and based on what I gleen from the publicly available information I believe cardiac and hepatotoxicity are too. So if we are overdosing children we are likely also increasing the likelihood of toxicities, now being children may mitigate this somewhat but still I expect to see problems in only a few years. (Elderly can die within weeks).

Lastly there is the problem of overusage. Presently over 1% of all children 6 - 17 are on atypical antipsychotics yet based on figures for schizophrenia and bipolar in this age range perhaps 1/10 that number might even have these illnesses. Plus for bipolar onset of symptoms do not mean that the disease is severe enough yet that an antipsychotic is indicated (it takes 6 - 8 years from onset to diagnosis and needing an antipsychotic and onset is determined in retrospect).

Anonymous said...

(Con't)

In 2007 at the American Psychiatric Association meeting there was a report from NYU that 43% of those refered who had a diagnosis of bipolar from a psychiatrist are actually misdiagnosed. This month the July issue of the Journal of the American Academy of Child and Adolescent Psychiatry reports a claim that there are children that are bipolar that simply have episodic (occassional) irritability instead of elevated mood. However elevated mood is the sine qua non for mania, so to me this is no more than trying to expand the diagnosis inappropriately.

In fact 2 weeks earlier the FDA advisory committee warned against using this as a basis for treating children as evidence indicates these children grow up to have depression and anxiety disorders and not bipolar disorder.

No one of course will remember this or the fact that these children were not part of the populations studied. That plus the fact that about half the children are also diagnosed with ADHD. and are on stimulants which likely increase cardiac toxicities when given in combination with antipsychotics makes the use of these drugs in children in practice truly frightening. Maybe that's why these companies only studied them for 3 weeks in children even all the practice guidances are pushing for lifelong treatment.


Now add on top of this the possibility that asenapine is significantly more toxic than these other drugs. Well you get the picture.

You may say but it isn't going to be approved for these populations. That is immaterial as the law clearly indicates an approval has to be based on how a drug is likely to be used.

Asenapine has an advisory committee coming up at the end of the month. If the FDA doesn't release all the reviews including clinical pharmacology, chemistry, and pharm/tox as has been their recent custom, or they are redacted (there should be no basis for redaction except for manufacturing methods and actual tablet composition) then you know that the FDA is trying to hide something. Even if they do release minority opinions FDA may try to dismiss concerns via other means. If they do this then you should look for if they make available the person who has the minority view for extensive questioning and defending their position. If not then it's a sham. n.b. that FDA typically gives the sponsor the FDA's analysis and slides and allows the sponsor to come up with rebuttals but reviewers don't get the same opportunity. This puts the evaluation of reviewers concerns at an extreme disadvantage.