Pfizer, the first company to get U.S. emergency use authorization for a COVID-19 vaccine, swung to a small profit in the fourth-quarter as it started shipping vaccines globally.

The drugmaker expects roughly $15 billion in revenue this year from the vaccine, which won emergency clearance in mid-December in the U.S. regulators and continues to rack up approvals across the globe. The two-dose vaccine is about 95% effective and is one of only a few vaccines available to check the global pandemic.

Rising medicine sales helped offset big increases in spending on research and production as the New York company manufactures hundreds of millions of doses of the COVID-19 shot and pushes forward on research gauging its effectiveness in different patient groups.

Fourth-quarter net income was $594 million, or 10 cents per share. A year earlier, Pfizer posted a loss of $337 million, or 6 cents per share, mainly due to a big writedown on the value of eczema drug Eucrisa.

Excluding one-time items, adjusted earnings came to 42 cents per share, or 4 cents shy of Wall Street projections.

The maker of the world’s top-selling vaccine, Prevnar 13 for preventing pneumonia and related bacterial diseases, reported revenue of $11.68 billion, up 12% from 2019’s fourth quarter. That beat Wall Street forecasts for $11.01 billion.

Pfizer expects full-year earnings in the range of $3.10 to $3.20 per share, with revenue in the range of $59.4 billion to $61.4 billion.

Shares are essentially flat before the opening bell.