Massachusetts health officials are streamlining the way the state issues licenses under its Medical Marijuana Dispensary program to prevent delays in treatment for those who qualify for it.

Department of Public Health Commissioner Monica Bharel on Wednesday said the licensing system has been "a confusing, overly lengthy process that has delayed appropriate patients from getting access" to medically needed marijuana.

Under the revised process, the dispensaries will be licensed in a format similar to pharmacies and other health care facilities, she said. The process will set high safety and suitability standards for dispensaries to meet, particularly when it comes to security and background checks, she added.

"This change will create a more efficient, market-driven licensure process that allows the commonwealth to maintain the highest standards of both public safety and accessibility," Bharel said in a statement.

The revised application process will formally launch May 15.

Bharel said dispensaries also will be evaluated individually, based on their ability to meet the standards.

The process of getting marijuana dispensaries up and running has bogged down in the licensing phase since Massachusetts voters approved a ballot question more than two years ago. The vote allowed up to 35 outlets to sell marijuana to qualifying patients. Those included people suffering from cancer, HIV, multiple sclerosis and Parkinson's disease.

To date, the state has issued only two certificates of registration and no dispensaries have opened.

Medical marijuana advocates have expressed frustration, saying the delays have harmed people whose suffering could be eased with marijuana. And Wednesday, Health and Human Services Secretary Marylou Sudders said the state has an obligation to license the dispensaries consistent with the voter-approved 2012 law.

"We must provide a more timely and transparent application process with the end goal of ensuring that patients have safe access to medical marijuana," Sudders said.

A trade association representing dispensaries called the change a positive step to helping dispensaries open their doors.

"It is critical that the department continue to prioritize resources to help existing licensees complete the process as quickly as possible so we can begin serving patients who have been waiting for far too long," said Commonwealth Dispensary Association Executive Director Kevin Gilnack.

The first certification of registration was given in 2014 to Alternative Therapies Group in Salem. On its website, the dispensary said it hopes to open to the public in early summer and by appointment only.

A second certificate was issued last week to New England Treatment Access Inc. to operate a marijuana dispensary in Northampton. The health department says the clinic will begin growing marijuana for medical use at a cultivation site in Franklin.

The company on its website says it hopes to open its Northampton clinic in the fall and is pursuing a second certificate for a clinic in Brookline.

The health department said 13 marijuana dispensaries have been provisionally certified and are currently in the inspection phase. The proposed dispensaries won't need to be reviewed again under the new process.

The agency said it will begin posting and updating the status of dispensaries in the approval and development pipeline and the number of registered and certified patients in the state on its website.