Lindley’s patients will visit the university three times to receive either marijuana, oxycodone, or a placebo before undergoing a battery of tests to assess their pain and look for side effects.

Getting DEA approval for the study took about six months from start to finish, says Newman, the regulatory manager—not including the time spent on renovations, which the university knew they would have to do before they even tried to get DEA approval. There was a ton of paperwork and a minor snag when the university put forth the name of a pharmacist to hold the DEA license—and be the person ultimately responsible for safeguarding the marijuana—without realizing the agency would only grant the license to a physician.

There was also a site visit by field officers from the local DEA office in Denver, who inspected the storage room and went over the rules for handling the drugs. They collected personal information and ran criminal background checks on everyone who’d have access to them. The field officers seemed genuinely interested and enthusiastic about the research, Newman says. But perhaps also slightly out of their element—the DEA is better known for cracking down on drug trafficking than for regulating research.

This summer, around the same time the DEA was reviewing the application for Lindley’s study, the agency was also considering two petitions to remove marijuana from its Schedule I listing of drugs “with no currently accepted medical use and a high potential for abuse,” which also includes heroin, LSD, and bath salts. Taking cannabis off that list would loosen some of the restrictions for researchers—like the requirement for narcotics lockers. But the DEA decided not to relist it after a scientific review by the Food and Drug Administration concluded that the evidence of medical benefits didn’t meet their standards.

Medical marijuana researchers were disappointed, if not entirely surprised by the decision, given the relative lack of research. Some noted yet another irony:

The restrictions imposed by the DEA make it more difficult to collect the kind of evidence that would convince the DEA to loosen their restrictions.

To be fair, satisfying the DEA isn’t the only hurdle marijuana researchers face. They must apply to the National Institute on Drug Abuse for access to marijuana grown at a government-run farm at the University of Mississippi, the only product they’re currently allowed to use (though the DEA announced this summer that it plans to allow additional growers to supply pot for research). They must file an “investigational new drug” application with the FDA. And as with all experiments involving human subjects, their studies have to be approved by an ethical review board at their institution.

Even that might not be the end of it. In Lindley’s case, the university spent $40,000 upgrading the ventilation system in the room where the patients will receive marijuana, to comply with its own occupational and environmental health policies. And the patients won’t even be smoking it—they’ll be inhaling vaporized cannabis.

All that’s been taken care of, finally, and Lindley is eager to get on with her study. She hopes to enroll her first patients by the end of the month. In Colorado and other medical marijuana states, a huge, unsupervised experiment is already underway. Given that so many people are already self-treating with marijuana, Lindley says, it’s important to know whether there are actually therapeutic effects. “I’m not a proponent one way or another,” she says. “I think we need to do the research.”

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