Moderna expects fewer 2021 Covid-19 vaccine deliveries than previously thought.

Moderna cut its 2021 forecast for Covid-19 vaccine deliveries on Thursday, pushing back some doses to next year and sending shares sharply lower.

The , which has soared to prominence this year on the success of its coronavirus , cited longer times for international shipments.

Other factors concern "temporary" impacts associated with the ramp up of production, said Moderna, adding that some shipments would lapse until early 2022.

Moderna now expects 2021 vaccine deliveries of between 700 and 800 million doses, down from the prior range of 800 million to one billion.

Moderna reported profits of $3.3 billion in the quarter from July to September, compared with a loss of $233 million in the year-ago period.

Revenues came in just shy of $5 billion, exponentially above the $157 million in the 2020 stretch, but below the $6.2 billion expected by analysts.

Moderna said it has agreements for $17 billion worth of sales in 2022 for vaccines, with options for another $3 billion.

The said commercial booster sales could also hit $2 billion.

Moderna's announcement comes after Pfizer earlier this week boosted its 2021 forecast as it ramps up production. The pharma giant now expects to deliver 2.3 billion doses in 2021 of the Covid-19 vaccine jointly produced with Germany's BioNTech, 200 million more than the company in July.

Shares of Moderna fell 16.6 percent to $288.50 in mid-morning trading.