AstraZeneca's ADRs tumbled more than 4% in premarket trade on Friday after the company's third-quarter profit fell short of expectations.

Disappointing sales of its top-selling cancer medicine Tagrisso in China, as well as high integration expenses from its recent acquisition, Alexion, dragged on the bottom line, which was only somewhat offset by the start of earnings from its Covid-19 vaccine, Vaxzevria.

In the third quarter, Vaxzevria made $1.05 billion in sales. The business had previously stated that once the pandemic emergency was over, it would stop its policy of selling the medicine for cost. It will continue to market the medicine to developing countries at a reduced price. Meanwhile, the company's capacity to earn profits on Vaxzevria is anticipated to be limited due to increased market share losses to vaccines made by Pfizer/BioNTech and Moderna, which have demonstrated greater efficacy rates.AstraZeneca sells COPD drugs for $270M - Delaware Business Times

Although Moderna was recently forced to lower its sales projection owing to production issues, Pfizer anticipates its Covid vaccine to bring in $36 billion in sales this fiscal year. It has also been temporarily halted in a number of countries due to possible ties to heart inflammation in certain age groups.

In the September quarter, the company earned $1.08 per share in earnings. Sales of all products increased by 47% to $9.74 billion. $9.86 billion was the total revenue.

It now forecasts a 27% increase in yearly income, including Covid vaccine sales. It estimates earnings per share to be around $5.23.