The Trump administration has selected five companies, including Moderna Inc, AstraZeneca Plc and Pfizer Inc, as the most likely candidates to produce a vaccine for the novel coronavirus, the New York Times reported on Wednesday, citing senior officials.
The other companies are Johnson & Johnson and Merck & Co Inc, according to the paper.
The selected companies will get access to additional government funds, help in running clinical trials, and financial and logistical support, the paper reported.
There is no approved vaccine for COVID-19, the respiratory disease caused by the new coronavirus.
The report did not mention potential vaccines from French drugmaker Sanofi, Novavax Inc and Inovio Pharmaceuticals Inc - among the more than 100 vaccines in development globally.
The announcement of the decision will be made at the White House in the next few weeks, the report said.
The White House did not immediately respond to a request for comment.
"We cannot comment on information that is market-moving," a US Department of Health and Human Services official said.
The companies on the list are the farthest along in developing a vaccine and have significant manufacturing capacity.
The United States is planning massive clinical trials involving 100,000 to 150,000 volunteers in total, with the goal of delivering an effective vaccine by the end of this year. To make that deadline, the government aims to start mid-stage testing in July.
The first two vaccines to start mid-stage trials would likely be from Moderna and the AstraZeneca/Oxford University combination, the director of the National Institutes of Health, Dr. Francis Collins, told Reuters in an interview last month. He said he expected vaccine candidates from J&J and Merck to eventually join the trial effort.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said on Tuesday that he hoped to have "a couple hundred million doses" by the start of 2021, according to a CNN report.