OTTAWA, Jan 17 (Reuters) - Canada on Monday approved Pfizer Inc"s (PFE.N) oral antiviral treatment for mild to moderate cases of COVID-19 in adults, but said global supply shortages meant only a few doses would be ready now. Rising infections and hospitalizations due the Omicron variant are forcing provinces to put in restrictions and the federal government to support impacted businesses. Officials predict COVID-19 cases will soar in coming weeks. "(This approval) is particularly important, as access to easy to use treatments could help to reduce the severity of COVID-19 in adults who become newly infected," chief public health officer Theresa Tam told reporters. Ottawa said last month it had signed a deal with Pfizer for a million treatment courses, pending approval. A global shortage means only a fraction will arrive soon. Canada has received 30,400 courses and officials said it will take delivery of another 120,000 by end-March. "We"re among the first countries to have approved the medication but also to have received the medication ... competition is high and we are doing a good job," Federal Health minister Jean-Yves Duclos told a separate briefing. Pfizer"s two-drug antiviral regimen, Paxlovid, was nearly 90% effective in preventing hospitalizations and deaths in patients at high risk of severe illness, according to clinical trial data. It is meant to be taken at home for five days beginning shortly after onset of symptoms. Ontario, the most populous of the 10 provinces, is seeing signs Omicron cases may have peaked, chief medical officer Kieran Moore told an Ottawa radio station. Official data show that as of Jan 8, 87.8% of Canadians aged 12 and older had received two doses of a COVID-19 vaccine. The U.S. authorized the Pfizer treatment for people ages 12 and older deemed at risk of severe illness last month. read more Canada is looking at whether to approve Merck & Co"s (MRK.N) oral antiviral pill, molnupiravir, which had less impressive results than Paxlovid in its pivotal clinical trial.