New U.S. Law Will Boost Marijuana Research

The Medical Marijuana and Cannabidiol Research Expansion Act will make it easier for researchers to access marijuana and study its therapeutic uses

A woman studies marijuana
 The federal government considers marijuana an illegal Schedule I drug, making it notoriously difficult to research. Sutthichai Supapornpasupad via Getty Images

President Biden signed a medical marijuana research bill into law last week, making it easier for scientists to access the drug to study its therapeutic uses. 

“For decades, the federal government has stood in the way of science and progress—peddling a misguided and discriminatory approach to cannabis,” Cannabis Caucus co-chairs Earl Blumenauer (D-OR), Barbara Lee (D-CA), Dave Joyce (R-OH) and Brian Mast (R-FL) wrote in a statement. “Today marks a monumental step in remedying our federal cannabis laws.”

Marijuana—defined legally as cannabis with more than 0.3 percent of the psychoactive compound tetrahydrocannabinol (THC)—has been legalized for recreational use in 21 states and several others have approved it for medical use. While doctors cannot formally prescribe marijuana, they can recommend it to patients with conditions ranging from severe and chronic pain to Alzheimer's disease to epilepsy and seizures. The FDA has approved a few THC-derived medications to treat nausea in patients undergoing chemotherapy and to treat loss of appetite in people with AIDS. Some research suggests the drug could be useful for treating depression and PTSD. Health effects include breathing problems, increased nausea and vomiting, anxiety and paranoia. The drug may also affect fetal development during pregnancy and brain development in young users.

The federal government considers marijuana an illegal Schedule I drug (on par with heroin and LSD), making it notoriously difficult to research. In states where the recreational marijuana market booms, medical research still lags behind

"The list of unanswered questions about marijuana is long—and disturbing," wrote Cindy Kiel, executive associate vice chancellor for research at the University of California, Davisin 2019 for the Association of American Medical Colleges (AAMC). "How does it interact with opioids or other drugs? Which conditions might it alleviate, and which of the hundreds of varietals might work best for which conditions? How much marijuana should patients consume, and how often? Is inhalation, ingestion, or transdermal application the best dosing strategy?" 

Currently, scientists are required to obtain permits from the Drug Enforcement Administration (DEA) for their studies, a process that can take a year or more, writes Science’s Meredith Wadman. Under the new Medical Marijuana and Cannabidiol Research Expansion Act, the Attorney General has 60 days to approve applications, request more information or provide reasons for denying them. 

Additionally, the law paves the way for universities and other entities to manufacture, distribute, dispense and possess marijuana for research, and it will allow researchers to amend their research protocols easier. It also requires the DEA to assess annually whether researchers have an “adequate and uninterrupted supply of marijuana,” per the law

For decades, the University of Mississippi was the only federally approved cultivator of the drug for scientists, though last year, the government approved six more entities. 

“We have one resource, and the highest concentration with THC [tetrahydrocannabinol] is 12 percent,” Ryan McLaughlin, a cannabis researcher at Washington State University, tells Bridget Balch of the AAMC. “That’s on the low end talking about the recreational market.”

The average potency of the cannabis flower is now around 20 percent THC, compared to 4 percent in the 1990s, per the AAMC. Some highly concentrated products contain more than 90 percent THC. 

The marijuana research act will also allow physicians to discuss the potential harms and benefits of marijuana and its derivatives with patients. 

Some say the new law still limits how scientists can do research because they cannot buy and study the products available to consumers in dispensaries. 

“There’s no substitute for studying real-world products that our patients and recreational consumers are using,” Staci Gruber, a neuroscientist at McLean Hospital in Massachusetts, tells Science

And the law won’t reschedule the drug, which many researchers have long pushed for. However, President Biden announced plans to review its classification in October. 

“[Rescheduling would] enable a lot more research,” Rosalie Liccardo Pacula, who studies addiction and cannabis policy at the University of Southern California, tells AAMC. “It means, with federal research dollars, we [could] examine the health effects of products already being used and sold in legal markets.”

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