Pfizer has reported a 78% jump in profit and reaffirmed the combined 2022 sales forecast of $54 billion for its Covid-19 vaccine and pill as demand for coronavirus products remains strong.

Shares rose 1% in premarket trading as overall net income rose to $9.91 billion despite a stronger dollar.

Sales of Pfizer's Covid-19 vaccine has driven much of its growth in the past year, and revenue is expected to be further bolstered by antiviral treatment Paxlovid, whose demand has surged in recent months following an uptick in US cases.

Paxlovid sales of $8.1 billion exceeded estimates of $7 billion, according to Refinitiv estimates.

The company said it had recorded a $450 million inventory write-off in the second quarter related to its Covid-19 products that had exceeded or are expected to exceed their shelf-lives.

Demand for the pill, which was used by President Joe Biden during his bout of Covid-19 infection, has picked up recently in the United States and other countries due to fresh outbreaks.

Pfizer has been banking on demand for vaccine boosters to drive up sales for the next few years.

The company and its partner BioNTech last month signed a $3.2 billion deal with the US government for 105 million doses of their vaccine, which includes supply of retooled Omicron-adapted booster, pending regulatory clearance.

The company now expects full-year adjusted profit of $6.30 to $6.45 per share compared to its prior forecast of $6.25 to $6.45 per share.