SALEM, Mass. —The first medical marijuana dispensary in Massachusetts opened Wednesday -- by appointment only -- nearly three years after voters overwhelmingly approved the drug's therapeutic use.

Patients lined up outside the Alternative Therapies Group's dispensary in Salem a day after state regulators signed off on its final paperwork.

Access to the dispensary in a converted factory building that houses other businesses will be restricted to patients with a state-issued marijuana registration card.

No marijuana is grown or processed at the Salem site. The company said their cultivation facility is not open to the public.

On its website, Alternative Therapies Group said Department of Public Health regulations prevent dispensaries from advertising the price of marijuana. Pricing is available only to qualifying patients and personal caregivers at the dispensary facility.

"Our pricing structure is aimed at providing medical-grade cannabis, grown with organic methods, in a safe environment at the lowest price,"...