Contrave is a treatment for obesity that consists of bupropion combined with naltrexone. An FDA advisory panel voted 13-7 for its approval in December. In the end of January, it is going for an official FDA decision.
Based on a variety of factors, we would hedge 60/65% in favor of its approval by the FDA. Additional data may be requested, however, to better explore its heart safety. Here’s why.
First, looking at the chemical ingredients.
Bupropion by itself is a commonly used antidepressant with eventual chemical similarity to stimulant type meds. It has been known to cause temporary, minor weight loss.
Naltrexone is a less commonly used treatment for addictions.
The theory is that naltrexone will act to prevent the weight loss effect of bupropion from being temporary.
One document looked at indicated that there have been more than 50 million uses of bupropion and a million uses of naltrexone. These are medications that have been very widely used for many years and have well known risk and side effect profiles.
The FDA in deciding on a treatment always balances two things. Efficacy vs safety. How effective a medication is for what condition must be weighed against how safe it is.
A treatment that is 99% cure for a type of advanced cancer, might be allowed to have the side effect of permanent infertility. But the same treatment as a 99% cure for high blood pressure, would likely not.
Contrave has moderate efficacy. It barely passes the standard of weight loss needed to meet the FDA’s official efficacy standards. That said, it does, and this is modestly significant weight loss.
At the same time, it has modest side effects. The main ones include a very minor increase in blood pressure/pulse rate and the potential for seizures.
The increase in blood pressure /pulse rate is exceptionally important as the FDA’s standard of heart safety has been very high for obesity medications. That said, it is minor, about 1 beat per minute, and it did not occur in everyone. Additionally, it tended to go away in those who lost weight.
This is a complex issue. Bupropion alone has similar effects on blood rate and it has been used millions of times with no cardiac issues that this author has heard of. Yet the FDA in the context of obesity meds is highly conservative and cautious.
That said, Contrave did not have two years of safety data as would ideally be looked for. It has potentially a risk management structure that might mitigate this.
Pros – has modest efficacy, and is made of two medications that have a great deal of experience of use, and that seem to have minimal side effects. The submission to the FDA at the advisory panel was high quality and indicates a company that knows what it is doing
Cons – modest efficacy. Heart rate increase is unsettling. Only 1 year of data. A conservative FDA.
These pros and cons alone would lead to a slightly negative impression. But there is a twist. The FDA has shot down two other obesity medications. Additionally, the FDA does not want the public to risk its health. Lack of approved treatments may lead to unhealthy use of supplements or off label use of meds.
With obesity a tremendous health concern, and the high safety shown in individual med use, plus the negative politics of likely non-approving two other meds – our projection turns positive.
There is a stipulation. This author has predicted perfectly FDA decisions, but predicts that this could be the one that ruins his record.