Ibudilast: MediciNova's Potential Meth Treatment Fast-Tracked
MediciNova, a small biopharmaceutical company in San Diego, recently received word from the U.S. Food & Drug Administration that one of their chief drug candidates, known as MN-166, has been fast-tracked by the regulatory agency as potentially the first approved treatment for addiction to methamphetamine.
In Japan, MN-166 is called Ibudilast, and it has been on the market for a different indication for more than 20 years.
The scope of methamphetamine abuse in the United States is not well known, reflecting a generally poor understanding of the drug and its effects in both the public and private sectors. Rough estimates put the number of users over the age of 12 at more than 1 million, but the number is likely much higher.
Currently No Specific Treatments
Currently, meth addicts have virtually no options in terms of treatment. The National Institute on Drug Abuse cites the Matrix Model as the current standard of care for this population:
The most effective treatments for methamphetamine addiction are behavioral therapies such as cognitive behavioral and contingency management interventions. For example, the Matrix Model, a comprehensive behavioral treatment approach that combines behavioral therapy, family education, individual counseling, 12-Step support, drug testing, and encouragement for nondrug-related activities, has been shown to be effective in reducing methamphetamine abuse.
Because there are no pharmacologic interventions approved for meth addiction, the FDA considers this an unmet need, which no doubt played a role in the agency's fast-tracking MediciNova's MN-166.
"MN-166 is the exact same drug that is approved in Japan," says Michael Coffee, MediciNova's Chief Business Officer. "The difference is that in Japan the dosage recommended is 30 mg per day. Our preferred dosing range, for all the indications we're working on, is 80-100 mg per day."
Despite the higher dosage, in early trials the company has not had any safety or major side effect issues to speak of.
"It's very helpful to already know the profile of a drug like we do with Ibudilast," says the company's Chief Scientific Officer, Dr. Kirk Johnson. "It gives us a head start towards understanding patient safety and seeking regulatory approval."
For Methamphetamine Only
When I hear the term methamphetamine, I think of crystal meth, of Desoxyn (pharmaceutical methamphetamine), of dextroamphetamine (Dexedrine), of Adderall, even Ritalin, leading me to wonder whether MN-166 would be applicable in treating patients addicted to amphetamines in general or just methamphetamine.
"In its approval the FDA would recognize it for methamphetamine and methamphetamine only," says Coffee. "Now, will addiction specialists want to try it with their patients? Maybe. But we would have nothing to do with that."
Considering the scope of the problem and the potential for a treatment, I think that addiction specialists would be very interested in trying the drug with their patients off-label regardless of the specific type of amphetamine.
The Approval Process
Meanwhile, the process to gain market approval continues. The company expects to begin recruiting for a phase II clinical trial soon for Ibudilast against methamphetamine, and as far as I know this will be the first of its kind.
Coffee and Johnson outlined the structure of the trial for me: It will be a 12-week outpatient study, with a recruitment target of 140 patients. Half of them will receive a placebo, and the other half will receive Ibudilast.
Participants do not have to stop using methamphetamine to qualify for the trial; in fact, they are almost expected to still be using it. The primary outcome of the trial will be whether, in the final two weeks of the trial, more subjects on Ibudilast were clean and not using meth compared to the placebo group.
In my experience, that's a rather unusual primary outcome measure for a clinical trial, but again, this is a first-in-kind trial, and its importance for this patient population can't be overstated.
While actual market approval for Ibudilast is still some time away, methamphetamine addicts and their loved ones can at least have some hope that help is on the way.
MediciNova is also exploring the potential for Ibudilast in treating opioid addiction, which we'll take a closer look at in an upcoming entry.