Posts tagged ‘william J Kennedy’

Forest Laboratories/Almirall aclidinium Advisory Committee Meeting

On Thursday Feb 23, 2012, the FDA Pulmonary-Allergy Advisory Committee will discuss the Forest Laboratories, Inc./Almirall S.A. aclidinium NDA for the treatment of COPD.

I find it interesting when the FDA includes the regulatory history in the Briefing Document, probably because it usually focuses right in on the issues.  In this case, it shows that the sponsor was given some advice on how to develop the drug by the FDA and chose to ignore it.

The FDA early on “suggested” that peak FEV and FEV AUC were the appropriate measures for a COPD trial.  The sponsor chose FEV trough.  Using this FEV trough, the sponsor provided an improvement of 60 ml vs the 150 ml they had offered in the Phase 2 trials.  The sponsor offered 1800 patients for safety at the recommended dose which the FDA said might be ok if the data were robust.  When the sponsor and FDA agreed that the 200 mcg dose was inadequate, the sponsor went back and did 2 more Phase 3 trials and then offered the FDA less than 1800 patients at the recommended dose of 400 mcg.  In this meager data base, there were patients with cardiovascular problems.

Anticholinergic drugs carry a risk of cardiovascular problems.  This is an anticholinergic drug.  The data base was too small to evaluate the cardiovascular risk of patients taking the recommended dose as chronic therapy.

The sponsor has probably failed on the efficacy measure with the FEV trough measure, hence the question from the FDA on the “clinically meaningful benefit” of the 400 mcg dose.  The sponsor failed to provide a data base that could adequately answer the question about cardiovascular risk for this anticholinergic drug. The sponsor will fail to gain the approval of the Advisory Committee.

PDUFA Date dapagliflozin

Well, the FDA has ruled on the AZN / BMY drug dapagliflozin for the treatment of diabetes.  It comes as no surprise that they feel the benefits do not outweigh the risks.  As was pointed out here in July 2011, the unknowns about safety that were also raised by the Advisory Committee, make for a difficult approval.  The only good thing that can be said for this new class of drugs is that the FDA has set the bar for approval.  Those that follow AZN and BMY with NDA submissions are well advised to clear the bar.

Diet Drugs in 2012

We’ve had several questions from readers asking if our opinion on the diet drugs that failed in 2011 has changed. Specifically, will Qnexa (or by extrapolation) or any of the other diet drugs have an easier go of it the next time around, ie, is the Cupcake Commentary still valid?

We’re going to take a slightly different approach with this posting and give our readers an insight into one of the changes we are thinking about for 2012 and beyond. We’re going to provide a more detailed commentary in this, the first response to our new feature, the Readers Forum.

Let’s start with the basic criteria for approval from the FDA Guidance on Diet Drugs. The draft guidelines from 2007 state that to prove efficacy, a diet drug must have two adequate and well controlled studies that demonstrate:

After 1 year treatment either:

  • There is a difference of 5% or greater between placebo and active drug OR
  • Greater than 35% of patients treated with drug have a difference of greater than 5% from baseline and twice the difference from placebo.

In earlier postings, we pointed out that the 5% difference is a very modest decrease in weight for a year and is comparable to having one less cupcake a week for a year for a 200 pound person. (200 lbs x 5% = 10 pounds; 10 lbs/52 weeks = 0.192 pounds per week, or about 3 oz, the size of a typical cupcake).

Let’s look at the data that were reported in the Briefing Documents prepared by the sponsors and the FDA for the Advisory Committee meetings that were held to discuss the diet drugs submitted for approval.

DrugEfficacySafety
LorqesFailed 5%- Tumorogenicity
QnexaPassed 5%
- Depression
- Memory Loss
- Metabolic Acidosis
- Increased HR
- Potential teratogen
- Lack of CV Date
ContraveFailed 5%
Passed 35%
- Increased SBP, DBP and HR
- MACE Inadequate
- Psychiatric AE

Let’s look at the alternatives to diet drugs. On one side are the diets and exercise that offer limited benefit and little risk. From purely anecdotal reports, if would appear that the General Motors Diet is the most successful. Many have not heard of this diet because nobody can make any money writing about it. It is the diet that has been used by the General Motors health professionals for years and is freely available on the Internet. Success is often reported as 5% weight loss in a week and safety is not an issue. Attendant with the success is often a change in eating habits.

On the other side of the diet drugs is gastric bypass surgery and its alternative, the stomach band. Success is reported as high as 30% weight loss in a year, a normalization of the diabetic state and a change in eating habits. Safety concerns include those associated with surgery and potential long term metabolic changes. It should be noted that this extreme surgical intervention is limited to those identified as obese and there is significant pre-screening qualification before the surgery and extensive monitoring afterward.

So, as a generality, diets can be said to be the least effective (as measured by sustained weight loss) for the majority of people but the safest, while gastric bypass surgery is currently the most effect but carries the most danger. Diet drugs tend to be between these two extremes, marginally more effective than diet alone but significant potential for more adverse effects.

Of course, the patient populations of these three treatments tend to be different. Diet and exercise is a treatment available to anyone, diet drugs for patients who need a bit more than the diet and exercise and bypass surgery generally reserved for those described as obese.

The FDA and its Advisors must determine if the diet drugs are safe and effective for the intended population, that is, those who fail diet and exercise alone but not so obese that they require bypass surgery.

Is there a regulatory precedent for this kind of treatment and this kind of population? I say yes. Recall the acne treatment isotretinoin or ACCUTANE as it was first marketed. Acne is a disease that can be treated with non-prescription drugs in the mildest condition, prescription drugs for those who don’t respond to the non-prescription drugs and for the most severe forms of acne, treatment with ACCUTANE is effective. Also like the use of diet drugs, acne treatment has a certain cosmetic component to it. By that I mean while there are certainly positive health components to treating both obesity and acne, treatment of both also usually results in a more attractive individual.

The ACCUTANE approval was held up because, like some of the diet drugs, it produced birth defects. The conventional wisdom whispered but never overtly expressed at the time was that this was a time bomb waiting to explode. One potential patient group was women of child bearing potential and clearing up acne had the potential to make their child bearing potential greater. Very restrictive labeling was proposed and rejected. The approval of ACCUTANE was delayed while this aspect of benefit risk was debated. When it was approved, and to this day, it carries a severe restriction requiring that women of child bearing potential have 2 negative pregnancy tests and be using 2 methods of birth control before it can be prescribed to them.

There is no reason to believe that the FDA has reduced its standards for drugs that have a potential for birth defects, especially if the drug has the potential for wide spread use in women of child bearing potential. Like ACCCUTANE, diet drugs have the potential to to make the child bearing potential of women of child bearing potential more potential.

Vivus has resubmitted its NDA for QNEXA with requested additional cardiovascular safety data to address issues that arose during the previous NDA review. These data will be reviewed at an upcoming Advisory Committee in February when the committee will have the opportunity to see the FDAs view of these limited data. It is likely the FDA will also ask the committee to comment on QNEXA use in women of child bearing potential, perhaps the reason the FDA has not insisted on included this population as a contraindication. Or perhaps they just feel it doesn’t make any difference because the drug still doesn’t have a benefit risk ratio that justifies approval.

NEXT TIME: Is it time for the FDA to revise the Guidance document for drugs used to treat obesity?

Transcept INTERMEZZO PDUFA Date

Transcept Pharmaceuticals (TSPT) is getting ready for it’s third Annual PDUFA Date coming up for INTERMEZZO for insomnia on Nov 27, 2011.  I think the results will be the same.  Why?  Because if you keep doing the same thing (submit NDAs with the same data) you can expect to get the same result – NFC from the FDA – Not Favorably Considered.

The FDA told them they had a problem with the dose in women, ie, it might be too high and there might be some carry over effects upon awakening that could present a problem.  In other words, the benefit risk ratio was tilted in the direction of risk.  So, the company lowers the dose in women by half, reducing the risk.  But what about the benefit side of the equation if you reduce the dose by half?  I don’t think they have the adequate and well controlled study on that.  So, we’ll probably get a chance to comment on this again next year when they celebrate their Fourth Annual PDUFA Date for this drug.

AZILECT (rasagiline) Advisory Committee Meeting

On Tuesday, Oct 17, 2011 the FDA’s Peripheral and Central Nervous System Advisory Committee will discuss TEVA‘s NDA for AZILECT (rasagiline) for use in slowing the progression of Parkinson’s disease.  AZILECT has been approved since 2006 for treating the signs and symptoms of Parkinson’s disease.

The FDA’s Briefing Document raises multiple regulatory issues which seem to support a negative view on approval by the FDA.  These include study design, adherence to protocol (especially regarding the analyses) and interpretation of the results. The FDA conclusion seems to be “We don’t know if there is an adequate study that can be done.  We don’t think the major study was designed to support the indication.  The major study did not adhere to the planned statistical analyses.  We think that the other study was even less well designed to support the indication.  The results of both studies do not support the indication for disease modifying.”

I think the most interesting discussion will be around Dr. Paul Leber’s paper on the design of trials to study this indication.