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Sales of the Covid-19 vaccine developed by Pfizer and BioNTech could reach up to $15 billion in 2021 and go higher if Pfizer signs additional supply contracts, Pfizer said Tuesday. The projections came as Pfizer projected full-year 2021 sales of between $59.4 billion and $61.4 billion, meaning that about one-fourth of estimated total sales will come from the Covid-19 vaccine. The forecast reflects "a continued recovery in macroeconomic and healthcare activity throughout 2021 as more of the population becomes vaccinated against Covid-19," Pfizer said. Pfizer reported fourth-quarter net income of $594 million, compared with a loss of $337 million in the year-ago period. For all of 2020, Pfizer reported profits of $9.6 billion, down 41.4 percent from 2019, with revenues up two percent to $41.9 billion. Pfizer's fourth-quarter revenues included $154 million in sales of the Covid-19 vaccine. The vaccine began winning approval from authorities late last year. Pfizer said it expects it could potentially deliver up to 2 billion doses in 2021 based on several factors, including adding more suppliers and contract manufacturers.