Minnesota's fledgling medical marijuana program is one of the least-used in the nation, after two months in business.

As of Friday, 460 patients were registered with the Health Department's Office of Medical Cannabis and could legally buy marijuana in Minnesota. Those numbers have been inching steadily upward and Michelle Larson, head of the OMC, expects the expansion to continue.

"We've seen steady increases in both providers and patients qualifying for the program since its launch," Larson said in a statement. "We expect those numbers to continue to rise as providers and patients learn more and get more familiar with the program."

Every state's medical cannabis program is different, she notes, and many have been operating longer and have much more open enrollment rules than Minnesota's new program. Direct comparisons of enrollment numbers may not be fair.

"Each state has taken its own approach to medical cannabis, and that makes it difficult to directly compare programs," Larson said.

But for now, Minnesota's enrollment is so low that Minnesota Medical Solutions — one of two companies authorized by the state to grow and sell the drug — announced last week that it would delay the opening of its next two clinics until next year.

Workers tend the cannabis crop at Minnesota Medical Solutions manufacturing facility in May. (Star Tribune photo by Glen Stubbe.)

"The patient numbers just don't justify immediately opening these satellite locations," MinnMed CEO Dr. Kyle Kingsley announced at the time. "It's strictly price control for our patients. We want to minimize expenses."

Of the two dozen states that have legalized medical marijuana, only Delaware had lower sign-up numbers than Minnesota's current tally, according to a 2014 survey by the site ProCon.org.

When Delaware's program launched in June, it had 340 registered participants. Minnesota, which had to get its entire program up and running in less than a year, had 90 registered patients on the program's first day.

Michigan, which legalized medical marijuana in 2008, has 175,870 active registered patients, according to the Michigan Department of Licensing and Regulatory Affairs.

When Illinois opened registration for a trial medical marijuana program last September, more than 2,000 patients rushed to sign up in the first few days — although the state's troubled program is still months away from seeing its first patients.

MinnMed, whose parent company will also be one of New York's newly designated cannabis suppliers, opened Minnesota's first cannabis dispensary at midnight on July 1, and opened a second state retail outlet in Rochester later in the summer. But plans for two more clinics in Moorhead and Eden Prairie in the fall have been pushed back to next year.

LeafLine Labs, which operates a dispensary in Eagan, is making plans to open a second storefront in St. Cloud this fall. The company plans to open two more locations, in Hibbing, Minn., and St. Paul, next year.

Minnesota has one of the most tightly regulated medical cannabis programs in the nation. By law, there can only be eight marijuana dispensaries statewide, and the drug can only be sold in pill or liquid form to Minnesota residents suffering one of nine serious conditions — including certain cancers and terminal illnesses, seizure disorders and Crohn's disease.

Patients who do qualify for the program — and who live close enough to a dispensary — can face the additional hurdle of finding a doctor, nurse or other health care professional willing to get them into the program. Under state law, patients need their primary caregiver to confirm to the state that they have a qualifying condition, but many clinics and physicians have balked.

As of Friday, 393 health care workers had registered with the state to certify patients. But the Health Department, citing concerns about privacy and doctor-shopping, will not disclose their names to patients searching for a physician who hasn't opted out of the program.

The Health Department is debating whether to expand the program to cover patients in intractable pain. Since pain patients make up the bulk of medical marijuana patients in most states, the designation could bring thousands of new participants into the program.

The department is staging a series of hearings around the state to invite public comment about the merits or concerns about expanding the medical cannabis program to pain patients.

The next two hearings will be in Moorhead on Tuesday, Sept. 15, and in Mankato on Sept. 21.

Jennifer Brooks • 612-673-4008