Shares of Moderna Inc rose 11% on Wednesday after the company signed a $1.5 billion deal with the U.S. government for the supply of its experimental coronavirus vaccine.

Moderna will provide about 100 million doses, with the price coming to around $30.50 per person for a two dose regimen. 

The company's vaccine candidate, mRNA-1273, is one of the few that have already advanced to the final stage of testing and is on track to be completed in September, the company said this month.

The deal confirms that Moderna's experimental vaccine is one of the leading contenders, said BMO analyst George Farmer, who has an "outperform" rating on the stock.

Effective vaccines and treatments are seen as essential in halting the COVID-19 pandemic, with the United States and the UK spending billions to reserve supplies of experimental vaccines.

Other countries, including Japan and EU members, have also signed deals for potential vaccines from AstraZeneca Plc AZN.L and Pfizer Inc.

With the U.S. contract now signed, other deals could follow, said Jefferies analyst Michael Yee, who has a "buy" rating.

"We assume other countries ... will want to secure deals out of sheer responsibility before the capacity of the major 3-4 players is locked up."

The U.S. deal would pay out in full if the vaccine achieves certain regulatory milestones before Jan. 31, 2021. 

Moderna shares, which have more than tripled and are among the top percentage gainers on the Nasdaq biotech index .NBI this year, were trading at $76.75 before the opening bell.

(Reporting by Manas Mishra in Bengaluru; Editing by Anil D'Silva) ((Manas.Mishra@thomsonreuters.com; www.twitter.com/Manasmishra24; within U.S. +1 646 223 8780, outside U.S. +91 806749 2709;))