PHOENIX — A former University of Arizona researcher will play a key role in an upcoming study that will aim to discover whether marijuana could be used as a Post-Traumatic Stress Disorder treatment for veterans.

According to a recent press release, Dr. Sue Sisley will be the principal investigator at the Multidisciplinary Association for Psychedelic Studies’ Phoenix site.

The first-of-its-kind $2.1 million clinical trial, which will be funded by the Colorado Department of Health, was formally approved by the U.S. Drug Enforcement Administration last week.

Sisley will oversee 38 veterans who have been diagnosed with the disorder and will participate in the randomized, placebo-controlled study.

“We owe it to these veterans to study this plant in a rigorous, controlled environment – and that is exactly what we intend to do,” she said. “This study is beyond reproach.”

A total of 76 veterans at both the Phoenix site and Johns Hopkins University in Baltimore will participate in the study by smoking marijuana, a delivery method that has drawn criticism from doctors who believe smoking itself is dangerous.

“Smoking is a legitimate delivery method,” she said. “I was very surprised to find out that there isn’t any published data confirming that smoking cannabis has any long term lung complications.”

The work could lead to a readily-available plant-based treatment method for PTSD, as opposed to alternatives that might be offered by pharmaceutical companies, Sisley said.

“They believe that the only research that should be done is isolating a certain cannabinoid in order to patent it to enable them to make lots of money, which is their business model,” she said.

Sisley said she was fired from the University of Arizona for conducting a similar study on campus. She said her research funding was cut in 2014, amid allegations of pressure from state lawmakers.

“They didn’t like the optics of veterans smoking pot on campus,” she said.

However, she said she believes it may have been for the best since it allowed her to focus her attention on the contentious nature of marijuana research.

“Even doing federally-legal cannabis research generates massive amounts of concern,” she said. “(Officials) treat it like its plutonium.”

The study is set to begin this summer and will last for at least two years, Sisley said.