Pfizer's shares rose about 4% in premarket trade on Tuesday, as stronger sales from its COVID-19 vaccination drove the firm to raise its full-year guidance.

At the midpoint of its projected range, the company now expects $81.5 billion in sales in 2021, including $36 billion in sales of Comirnaty, its COVID-19 vaccine. This is a $2.5 billion increase over the previous estimate. However, the non-COVID vaccination business is now seen as slightly weaker, with sales forecasted at $45.5 billion at the midpoint, down from $46 billion previously.

Increased immunizations against the pandemic around the world drove up group sales in the third quarter, which were 130% higher than a year before at $24.1 billion. The adjusted profit per share was $1.34, which was also beyond expectations.

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The projected revenue from COVID-19 vaccinations is based on 2.3 billion doses expected to be delivered in 2021 under already-signed contracts, up from 2.1 billion doses previously committed. The COVID vaccination was expected to bring in $33.5 billion in sales at the time.

The quarter's forecast was hampered by the recall of Chantix tablets due to quality difficulties. Shipments of the product have subsequently been halted by the company. Chantix is a smoking cessation medication that is only meant to be used for a limited period of time. However, examinations revealed that the drug contained an excessively high quantity of a carcinogen.