(Reuters) -Merck & Co said on Wednesday it would supply 60,000-100,000 doses of its experimental COVID-19 treatment to the U.S. government for up to about $356 million. The agreement will help support advanced development and large-scale manufacturing of the company’s investigational therapeutic MK-7110 to treat hospitalized patients with severe or critical COVID-19, the U.S. Department of Health and Human Services said. The funding allows for development of MK-7110, including completing activities required to request emergency use authorization from the U.S. Food and Drug Administration, and for delivery of the doses by June 30, 2021. Merck has built out its portfolio of COVID-19 treatments through a series of deals in recent months, including the acquisition of drugmaker Themis and a partnership with Ridgeback Biotherapeutics LP. The company in November agreed to buy OncoImmune in a $425 million deal that gave it control of MK-7110, a promising first-in-class fusion protein and immune modulator. Immune modulators have the potential to minimize the damaging effects of an overactive immune response to COVID-19. Interim data from September showed that the therapy, which is administered as an injection, increased the likelihood of symptom improvement in serious COVID-19 cases and also reduced the risk of respiratory failure and death. The doses will be made available to the American public at no cost, the agency said. The United States has authorized two vaccine for emergency use this month and more than 600,000 Americans had received their first COVID-19 vaccine doses as of Monday, but the need for treatments for those hospitalized remain high. Merck is also working on two potential vaccines that are still in early stages of development. It is also collaborating with Ridgeback in developing an antiviral treatment called molnupiravir. The company’s shares rose nearly 1% to $80 on Wednesday.