Ketamine Seems to Ease Depression. We’ll Soon See What Else It Does.

(Bloomberg Opinion) -- Clinical trials are not enough to prove any drug is safe and effective – especially one that could be as widely used as Johnson & Johnson’s depression drug esketamine, a slightly altered form of the street drug ketamine. The FDA approval process is a balancing act, weighing safety and efficacy testing against the need to get potentially life-saving drugs out as soon as possible.

An advisory panel to the FDA decided this month that the benefits outweigh the risks, and approval is expected soon. But scientists who study depression say there’s a lot more to learn about esketamine’s long-term effects.

While best known as a recreational drug, ketamine has been used since the 1970s as an anesthetic, in doses much higher than what’s likely to be given to depression patients. The trials so far seem to show that the drug is not highly addictive, according to a story in the medical website STAT. But time will tell.

The most promising clinical trials followed people whose depression had been resistant to conventional therapy. Fifty percent of patients improved when given conventional therapy plus a placebo, as compared to 70 percent who got conventional therapy and esketamine.

Taking the drug will be a lot more complicated than taking Prozac. It’s been formulated so that it can be delivered as a nasal spray, but people have to get the drug at a doctor’s office, and they won’t be allowed to drive for at least 24 hours, said Gerard Sanacora, a Yale University psychiatrist who has been involved in the clinical trials.

He said he believes there’s potential for benefit, because the drug works for some people who get no relief from conventional treatments and because works faster, which might even prevent suicide. But there’s a lot more to learn about the drug’s potential long-term consequences. So far it looks like people will get two treatments a week to start, then one for maintenance. But scientists don’t know whether it can be tapered down further, or discontinued, and whether there’s a risk for relapse, he said.

Sanacora said that ketamine is based on a very different model of how depression works. Standard therapy is based on the principle that depression is a chemical imbalance involving the transmitting chemical serotonin. But an alternative view started to take shape in the 1990s that depression was more of a problem with the connections between neurons, triggered by chronic stress and mediated by something called the glutaminergic system.

Because ketamine interacts with this system, researchers started testing it as a depression drug. Although it seems effective, there’s still no agreement on how depression actually works – and there is some concern that it might work very differently in different patients.

Ketamine can affect cardiovascular health, and in the short term can cause patients to lose their sense of their bodies’ position in space – the sense of proprioception. They sometimes feel their arms are floating.

That hasn’t stopped people from flocking to clinics to get treated with IV ketamine infusions for depression and other problems. This is legal because the drug is approved for anesthesia, and prescribers can use it off-label for other purposes. An investigation by the medical website STAT raised concerns that clinic staff didn’t have the necessary expertise, and there was considerable marketing hype in many cases. The infusions cost between $350 and $1,000 each, and can go on for five or six treatments.

Another red flag popped up last week when the Boston Globe ran a story about three women who claim to have been sexually abused by psychiatrist Keith Ablow – a frequent commentator for Fox News. The Globe reported that Ablow was treating the women with ketamine, and one expert cited in the lawsuits said a patient had become “very dependent on this medication and dependent on Dr. Ablow to supply it.”

Ablow’s Twitter feed is full of positive stories about ketamine in places such as Reader’s Digest, followed by a phone number to call for a “free ketamine screening.” The allegations illustration that it’s not just patients that will need to be tracked for abuse, but the doctors as well.

On the positive side, FDA approval would give patients who want the drug a standardized treatment that would be covered by many insurance plans. Approval also creates an opportunity to collect data on longer-term use. (An earlier column exploring the promise of big data in medicine points out that clinical trials are often not long-running enough or big enough to catch even deadly side effects.)

Yale’s Sanacora thinks of the next series of trials as Phase 4. Sanacora also brought up what he poignantly called the “Flowers for Algernon” effect, referring to the short story in which the main character, Charlie Gordon, is treated for an intellectual disability. The treatment works, but eventually wears off, leaving Charlie back where he started. The disappointment makes for a tragic tale. An arc like this would be the last thing depression patients need – though if no other treatment is helping, it might be a risk worth taking.

To contact the editor responsible for this story: Philip Gray at philipgray@bloomberg.net

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Faye Flam is a Bloomberg Opinion columnist. She has written for the Economist, the New York Times, the Washington Post, Psychology Today, Science and other publications. She has a degree in geophysics from the California Institute of Technology.

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