SPRINGFIELD, Ill. (AP) — Illinois could see changes this year that expand access to medical marijuana, as operators say the number of patients allowed to buy the drug is too low to recoup investments.

The Chicago Tribune reports that retail sales of medical cannabis in Illinois only topped about $9.3 million last month. Revolution Enterprises CEO Mark de Souza says his two marijuana cultivation facilities in the state are operating at less than 30 percent capacity.

Operators say the low patient count is because of constraints that state law imposes on Illinois’ pilot program. The program expires in 2020.

Gubernatorial candidates are discussing medical and recreational marijuana on the campaign trail. A plan also has been introduced in the Legislature that would allow patients qualifying for prescription opioids to access medical cannabis.