Coronavirus updates: Space Force's second in command tests positive

Eli Lilly and Company announced Wednesday an initial agreement with the U.S. government to supply 300,000 vials of one of its experimental antibody treatments for $375 million to help fight the coronavirus pandemic.

The federal government will accept the vials of bamlanivimab, a monoclonal antibody drug, if it is granted emergency use authorization by the U.S. Food and Drug Administration. The initial agreement also provides the option for the federal government to purchase up to an additional 650,000 vials through June 2021, according to a press release from Eli Lilly and Company.

The Indianapolis-based pharmaceutical firm submitted a request earlier this month for the FDA to authorize emergency use of bamlanivimab in non-hospitalized, high-risk individuals with mild to moderate cases of COVID-19.

"The U.S. is experiencing a surge in COVID-19 cases and associated hospitalizations," said David Ricks, chairman and CEO of Eli Lilly and Company, "and we believe bamlanivimab could be an important therapeutic option that can bring value to the overall healthcare system, as it has shown a potential benefit in clinical outcomes with a reduction in viral load and rates of symptoms and hospitalizations."

If the FDA authorizes use of the therapeutic, the federal government will allocate the doses to state and territorial health departments which will then determine which health care facilities receive the drug for use in outpatient care. The government-purchased doses would become available to Americans at no cost, though health care professionals could charge for administering the intravenous infusion, according to a statement from the U.S. Department of Health and Human Services.

"This agreement with Eli Lilly is part of Operation Warp Speed’s efforts to position the federal government to distribute potential therapeutics, allowing faster distribution if trials are successful," said Secretary of Health and Human Services Alex Azar.

The deal comes after the National Institute of Allergy and Infectious Diseases announced Monday that it has stopped testing a combination of bamlanivimab with the antiviral medication remedesivir in hospitalized COVID-19 patients, after an independent review of results found a "lack of clinical benefit." Eli Lilly and Company said that all other studies of bamlanivimab, including its own phase 3 clinical trials, will continue and that it remains "confident" that the drug may help prevent progression of COVID-19 for individuals earlier in the course of their disease.

Russia registered 346 more deaths from COVID-19 in the last 24 hours, setting a new national record, according to the country's coronavirus response headquarters.

The country's previous record of 320 deaths in a 24-hour reporting period was set just a day earlier.

An additional 16,202 new cases of COVID-19 were also confirmed in the past day, down from Sunday's peak of 17,347, according to Russia's coronavirus response headquarters.

Moscow remains the epicenter of the country's outbreak and recent surge. More than 22% of the new cases -- 3,670 -- and over 21% of the new deaths -- 61 -- were reported in the Russian capital.

The nationwide, cumulative total now stands at 1,563,976 cases with 26,935 deaths, according to Russia's coronavirus response headquarters.

The Eastern European country of 145 million people has the fourth-highest tally of COVID-19 cases in the world, behind only the United States, India and Brazil, according to a real-time count kept by Johns Hopkins University.

ABC News' Alina Lobzina contributed to this report.

South African President Cyril Ramaphosa is under self-quarantine after a guest at a dinner he attended over the weekend tested positive for COVID-19.

"The President is showing no symptoms at this time and will, in line with COVID-19 health advice, be tested should symptoms manifest," Ramaphosa's office said in a statement Wednesday. "The President will perform his duties remotely and will observe the guidelines that apply to self-quarantine."

Ramaphosa attended a fundraising dinner for the Adopt-a-School Foundation at a hotel in Johannesburg on Saturday evening. Thirty-five guests were in attendance at the event and were the only people hosted by the venue at that time.

"The event adhered stringently to COVID-19 protocols and directives on screening, social distancing and the wearing of masks," Ramaphosa's office said. "As was the case with all guests, the President himself removed his mask only when dining and addressing the guests."

On Tuesday, the Adopt-a-School Foundation advised the dinner guests that an attendee had tested positive for COVID-19 after showing symptoms on Sunday. The South African president had already attended two other events Tuesday morning before being alerted of the infected guest, who is currently "receiving medical attention," according to Ramaphosa's office.

"The President is screened regularly by the South African Military Health Service and subjects himself to screening at venues where he participates in engagements," his office said.

South Africa has confirmed more than 717,000 cases of COVID-19 since the start of the pandemic, including at least 19,053 deaths. The country accounts for almost half of all diagnosed cases on the African continent, according to data from the Africa Centers for Disease Control and Prevention.

Russian Foreign Minister Sergei Lavrov is self-isolating after coming into contact with someone infected with COVID-19.

Lavrov, however, is "feeling well," according to Russia's Ministry of Foreign Affairs.

"Following a contact with an individual infected with Covid-19, Sergei Lavrov will opt for self-isolation," the ministry said in a statement Tuesday. "The visits and meetings planned earlier are postponed."

ABC News' Tanya Stukalova contributed to this report.