Moderna might seek emergency approval this fall of coronavirus vaccine for health care workers

But Cambridge biotech is still sticking to its 12- to 18-month projection for wide availability

Laboratory equipment at Moderna in Cambridge.Adam Glanzman/Bloomberg

The head of Moderna says the Cambridge drug company may seek federal emergency approval of its experimental coronavirus vaccine for some people in the fall, although the product wouldn’t be commercially available for at least 12 to 18 months.

Stephane Bancel, its chief executive, told representatives of Goldman Sachs that “it is possible that under emergency use, a vaccine could be available to some people, possibly including healthcare professionals,” according to a filing Monday with the Securities and Exchange Commission.

Bancel’s statement startled Alan Carr, an analyst at Needham & Co., who wrote to investors last week that he assumed no vaccine would be available until 2021, at the earliest — a view shared by many experts on vaccines.

“It’s a surprising development, and [Bancel’s] comments may be a reflection of discussions with the FDA in terms of what they might want" before granting an emergency use authorization, Carr said.

Moderna last month became the first drug maker to deliver a potential COVID-19 vaccine for clinical trials to the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health. The institute helped develop the vaccine.

Forty-five healthy volunteers on March 16 began receiving doses of the vaccine, which relies on custom-built messenger RNA to produce an immune response, in a clinical trial in Seattle. The first phase of the trial, at Kaiser Permanente Washington Health Research Institute, is scheduled to run about six weeks. If all goes well, the vaccine will then probably undergo two more phases of testing on many more people.

Experts have consistently said it will probably take at least a year before a vaccine made by any company could be deployed, assuming that it wins approval.

In the SEC filing, Bancel confirmed that the company is preparing to expand its manufacturing capacity for the production of millions of doses a month in the potential form of individual or multi-dose vials. Moderna has a $130 million plant in Norwood with limited capacity and might hire a contract manufacturing organization to ramp up production.

There’s no approved vaccine for COVID-19, but the World Health Organization lists more than 40 vaccine candidates around the globe. Several of the efforts underway have been launched by firms with a presence in Massachusetts or partnerships with laboratories in the state.

An emergency use authorization enables the FDA to allow use of unapproved medical products in an emergency caused by chemical, biological, nuclear, and other threats. Last month, Alex Azar, secretary of Health and Human Services, determined that COVID-19 constituted such a scenario.

The FDA recently issued several emergency authorizations for high-speed test kits to diagnose the coronavirus, including products made by Waltham-based Thermo Fisher Scientific and Marlborough-based Hologic.

But emergency use authorizations for vaccines appear to be rare. In 2005, the government granted one for military forces that might be at risk for inhaling anthrax spores in an attack, according to the FDA’s website.

Dr. Dan Barouch, head of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center, welcomed the possibility of the government speeding approval of a coronavirus vaccine. His center is collaborating with Janssen Pharmaceutical Cos., the drug-making arm of New Jersey-based Johnson & Johnson, on a rival effort to use a common cold virus to deliver a tiny part of the coronavirus protein into cells to stimulate the immune system.

“Approvals should be fast-tracked, but only if safety and potency have been shown convincingly,” said Barouch, whose lab is testing multiple versions of the experimental vaccine on mice, ferrets, and rhesus monkeys.