Regeneron will work with the U.S. government to develop antibody treatments for the new coronavirus from China, disclosing Tuesday an expansion of a partnership that previously yielded an experimental drug cocktail for the Ebola virus.

The Tarrytown, New York-based biotech is one of roughly a dozen drugmakers now working on treatments for the coronavirus that emerged late last year in Wuhan, China. Most are smaller companies unlikely to possess sufficient funds to run large-scale tests, although Johnson & Johnson and Gilead have announced initial efforts in recent weeks.

So far, the viral pneumonia-like disease has spread to 23 countries, infecting 20,630 people as of Tuesday and killing more than 400, according to figures from the World Health Organization.

Using Regeneron’s experience with Ebola as a gauge, readying antibodies for testing against the novel coronavirus will likely take months, and trials thereafter could take years to set up and return results.

Still, Regeneron and a U.S. government official were confident the partnership could move quickly, noting the company’s past experience in responding to viral outbreaks.

“We anticipate that timelines could be as rapid as we have seen in the past, or possibly even faster given the maturity of the platform,” said Rick Bright, director of the Biomedical Advanced Research and Development Authority, or BARDA, at the Department of Health and Human Services.

“In parallel, the U.S. government has already initiated planning for clinical evaluation to assess safety and efficacy of the candidate,” Bright added in comments emailed to BioPharma Dive.

Governments and health agencies are scrambling to respond to the public health threat from the novel coronavirus, dubbed 2019-nCoV. It’s still unclear how wide the virus will spread and how lethal it ultimately will be, but rapid spreading has galvanized global and national authorities into action.

The WHO last week declared the outbreak a global public health emergency and HHS followed suit with a U.S. emergency declaration Friday.

No funding commitments from HHS to Regeneron were announced Tuesday, but under a 10-year agreement signed in 2017, the agency will pay for 80% of R&D and manufacturing costs after selecting the antibodies it plans to advance.

Producing a drug candidate quickly is an achievement, but ultimately only one step in a development process that can stretch for years. In addition, viral outbreaks are challenging environments to assess new treatments through randomized, controlled trials.

Regeneron, for example, developed a combination of three antibodies against Ebola in six months following a 2014 outbreak of the deadly virus in western Africa countries.

While the company was able to validate its drug cocktail in healthy volunteers soon after, the crisis passed before the company could test its efficacy in protecting people from the virus.

Three years later, Regeneron restarted its initial work in response to another Ebola outbreak in the Democratic Republic of Congo. A trial begun in late 2018 was stopped early last August after investigators found Regeneron’s drug and another treatment from the National Institutes of Health helped prevent more people from dying than an antibody regimen known as ZMapp.

The study, as well as the companies and government groups involved with it, benefited from the decades of scientific work on Ebola — research that also led to development and the recent approval of a vaccine from Merck & Co.

The new coronavirus from China, which shares similarities with the SARS and MERS viruses, will test drugmakers drawing from a limited arsenal of potential treatments.

“This is the third CoV jumping from animals into the human population over the past 15 years and it’s unlikely to be the last, yet there are no licensed diagnostics, therapies or vaccines,” said Bright.

“The time is now to get these products for coronaviruses over the finish line.”

In early January, as the severity of the 2019-nCoV outbreak became apparent, Chinese authorities made the virus’ genetic sequence available to researchers globally.

But no in vitro or animal models of the virus currently exist in the U.S., according to Christos Kyratsous, head of infectious disease R&D at Regeneron, potentially adding to the development challenge.

Regeneron and HHS are collaborating under a 2017 agreement that provided for development of treatments against as many as 10 pathogens that “pose significant risk to public health” — so far, influenza and 2019-nCoV.

“We are going to be evaluating the data together,” Kyratsous said in an interview. “We won’t scale something up unless both us and BARDA believe this is something that has the potential to work.”

In its statement, HHS said BARDA is also reviewing other potential vaccines and drugs to identify effective treatments against the virus. Regeneron has also worked with BARDA on an experimental two-drug treatment for MERS.

Most of the companies announcing drug development efforts against 2019-nCoV are smaller biotechs, some with histories of trumpeting research programs in the wake of past viral outbreaks.

Larger drugmakers J&J, Gilead and GlaxoSmithKline have also said they would begin testing or partnership work to assist in the global effort.