Bay Area biotech companies are joining the race to develop or repurpose drugs to treat the fast-spreading Wuhan coronavirus, but testing and manufacturing will likely take longer than the current outbreak will last.

Foster City’s Gilead Sciences is working with U.S. and Chinese researchers and regulators to determine whether its experimental antiviral drug remdesivir works on the new coronavirus, 2019-nCoV. Remdesivir has not been licensed or approved in any country. But it has been tested and has shown some activity against the Ebola virus and two other types of coronaviruses, SARS (severe acute respiratory syndrome) and MERS, in animals or in test tube experiments.

Gilead said Friday it has provided remdesivir to a “small number of patients” with the new virus as an emergency treatment, and is working with Chinese officials to set up a study on the drug’s safety and effectiveness against the virus. The drug had been in clinical trials for Ebola patients in the Democratic Republic of Congo, but was discontinued in 2019 after other drugs were found to be more effective.

The novel coronavirus, believed to have originated in Wuhan, China, has stricken thousands of people, mostly in China, and led to 213 deaths as of the official count Friday. In an effort to halt the spread beyond China, the United States has advised against travel there, and airlines are canceling flights.

Vir Biotechnology, a 3-year-old San Francisco immunology company that focuses on infectious diseases, is testing whether its technology— which has identified antibodies against Ebola, Zika and malaria — can identify injectable antibodies to act against the new coronavirus.

“If we were to identify such an antibody, then we have to develop it, have it manufactured, go through the regulatory process and get it to people as quickly as we can,” said Vir CEO George Scangos. “Everyone has an interest in making this happen as quickly as possible.”

Previous epidemics, such as Ebola and the H1N1 “swine flu,” have prompted a flurry of announcements from drug companies on new initiatives to research whether drugs already in their pipelines can be repurposed or combined with others to target new viruses. Coronavirus is no exception: In addition to Gilead and Vir, more than half a dozen drug companies, including global firms AbbVie, Johnson & Johnson and Merck, have begun testing their drugs for potential against the spread of the new coronavirus.

Some, like Moderna Therapeutics of Cambridge, Mass., and Inovio Pharmaceuticals of Pennsylvania, have received millions of dollars from the Coalition for Epidemic Preparedness Innovations, an Oslo-based coalition of public, private and philanthropic organizations, to develop vaccines against the new virus. Vaxart, a South San Francisco biotech firm that makes oral tablet vaccines, announced Friday it is starting a program to develop such a vaccine.

Some biotech analysts are skeptical that drugs can be identified, tested for safety and manufactured in time to help contain the current outbreak. Vaccines take months, if not years to test for safety and effectiveness.

“I don’t have a ton of confidence they’re going to get something quickly,” said Madhu Kumar, an analyst at R.W. Baird who follows the biotech industry. “Getting something done quickly has nothing to do with the companies. It has everything to do with drug development taking a long time. ... By the time they get something that could potentially work, knock on wood, this pandemic will be over and it’ll be hard to see a path forward.”

Vaccines and treatments for epidemics rarely make money for drug companies because they are typically not recurring or predictable like the flu, for which a vaccine is needed each year, Kumar said.

“SARS, Ebola, the coronavirus today — they don’t really pop up regularly enough where you can reliably manufacture medicines in a way that will be profitable,” Kumar said. “They’re basically kind of altruistic efforts on companies’ part.”

Vir’s stock climbed 64% to $27.12 a share after the company’s coronavirus announcement. Gilead’s stock price has not reacted as favorably, hovering around $64 per share. Spikes in stock prices will likely be temporary, Kumar said.

“Invariably, reality settles in. It’s a a combination of, ‘This isn’t going to happen,’ and also the outbreak leaves people’s minds, so it’s not as important anymore,” he said.

Catherine Ho is a San Francisco Chronicle staff writer. Email: cho@sfchronicle.com Twitter: @Cat_Ho

Correction: A photo caption in an earlier version misspelled the last name of Corey Momont, a research assistant who works in a lab at the San Francisco company Vir.