Why are there so few clinical trials on baclofen in alcohol addiction?

One of the major arguments from critics of baclofen treatment for alcohol addiction is that there are not enough clinical trials to support its wider use. It seems odd that there are not lots of trials when baclofen is recognised as a promising treatment for alcohol addiction, a common and lethal problem with devastating effects on health and social functioning. Given the other treatment options are not effective for many patients, any new treatment should be very welcome.

So why aren’t there lots of good clinical trials on baclofen? It’s not for lack of patients – there are plenty of alcohol addicted patients who would be willing to try a new treatment.

As I discussed in the “If baclofen is so great, why isn’t everyone using it” section, it largely comes down to the fact that baclofen is not a newly discovered medication. Because it was released over 40 years ago, it’s no longer protected by a patent so is cheap and can be produced by any pharmaceutical company that wishes to make it.

This is the crux of the problem. Clinical trials of medications are expensive and it’s usually a pharmaceutical company that funds them. So fundamentally, this is a simple problem of money.

It’s very expensive to run large clinical trials. The largest baclofen study undertaken to date, the Bacloville trial in France (https://clinicaltrials.gov/ct2/show/NCT01604330 ) cost AUD$1.9 million (1.2 million euros) for 320 patients seen in routine general practice visits over 1 year and prescribed a very cheap medication (or placebo). That’s nearly $6000 per patient for this pretty simple trial.

Most of the money for clinical trials of medications is provided by pharmaceutical companies. When they manufacture a new medication they need to test the medication on patients. So the company pays doctors or hospitals who have suitable patients in their care to test the medication on them. It’s a “win-win” situation. The pharmaceutical company gets the clinical trial results it needs to market the medication. Clinicians have an easy source of funding to trial new medications which may be more effective for the patients they treat.

But this arrangement doesn’t work if the medication is out of patent. There’s no benefit to a company in funding research to extend the medication’s use because if it shows benefit, other companies will make the medication too. These other companies will reap the benefits of the clinical trial without having paid for it. This means that pharmaceutical companies are not interested in funding expensive clinical trials on out of patent medications and there are few alternative sources of funding for clinical trials on medications.

In fact it’s worse than just disinterest. The pharmaceutical companies are actively resistant to baclofen becoming widely used for alcoholism treatment.  They would much rather develop new medications for alcohol addiction that would be protected by patent to stop anyone else producing them. The price of any new medications could and would be set high to get the maximum profit from sales.

But baclofen is very effective and very cheap. So if baclofen became widely used and accepted as the usual treatment for alcohol addiction, it creates a problem for pharmaceutical companies trying to get into the potentially lucrative market of alcohol addiction treatments. The BACLAD study (link) on baclofen showed an impressive 68% abstinence rate at 3 months or 44% improvement over placebo for a drug which costs a pittance. That sets the bar very high in terms of cost:benefit ratio and this will be hard to beat. Any new alcohol addiction treatment would need to be substantially more effective than baclofen to justify being substantially more expensive. That’s a big ask when baclofen is already so effective. The pharmaceutical companies would much rather be competing against the largely ineffective current medications, naltrexone and Acamprosate, which only show 10% improvement over placebo.

There are studies looking at baclofen in alcoholism: here is a brief summary. There is a more detailed description and discussion in the Science section of this website:



There are two large French studies of baclofen in alcoholism in the pipeline now. Bacloville (https://clinicaltrials.gov/ct2/show/NCT01604330 )
Alpadir (https://clinicaltrials.gov/ct2/show/NCT01738282 ), both started in 2012, seven years after the publication of Olivier Ameisen’s case report of his own baclofen treatment in the journal Alcohol and Alcoholism (link) .

By 2012, the “baclofen situation” in France had become untenable- there were over 20,000 patients being treated with baclofen for alcohol addiction but no large clinical trials underway for the above reasons. The French government bowed to public pressure and made $1.2AUD (750,000 euros) available for the Bacloville trial. An anonymous donor donated $700,00AUD (450,000 euros) to bring the total to the required $1.9 million AUD (1.2 million euros) to undertake Bacloville.

Shortly after Bacloville was announced, a small French pharmaceutical company Ethypharm launched it’s own study, Alpadir, with the aim of applying for authority to sell baclofen for alcohol addiction treatment in higher dose tablets (up to 60mg) for a higher price. In France, only 10mg tablets are currently available and they believe patients on high dose baclofen will pay a premium for convenience.

Both have finished collecting patient data including the one year follow up. The results of both studies will be announced on September 3rd 2016 at the World Congress for Alcohol and Alcoholism in Berlin (World Congress for Alcohol and Alcoholism in Berlin on September 3rd 2016). Each study has ~300 patients, making a combined total of over 600 patients, and both are randomised controlled trials (RCT) comparing baclofen to placebo. The protocols and exclusion criteria are somewhat different between the two trials. Both are discussed in more detail in the Science section .

In the meantime the BACLAD study was published in 2015 and showed good evidence of baclofen’s efficacy in a rigorously controlled but small trial (link) .

It is hoped that the release of the results of the Bacloville and Alpadir trials in September 2016 will finally put an end to calls for more trials to be performed before baclofen is acknowledged as a valid treatment option for alcoholism.

A problem for any future trials is that the increasing use of baclofen means that most patients who struggle with alcoholism want to be treated with baclofen rather than participate in clinical trials. That’s understandable, given the health and social problems of alcohol addiction.