BENGALURU (REUTERS) - Moderna said on Wednesday (June 8) an upgraded version of its coronavirus vaccine produced a better immune response as a booster dose against the Omicron variant than the original shot in a study.

The trial results raised the company's hopes that the vaccine will be used in an inoculation drive in the fall season.

Moderna will submit the data to regulators "in the coming weeks", and expects it to get clearance in late summer.

As the overall demand for vaccinations declines, companies have shifted gears and are targeting a more competitive booster dose market.

In the study, which did not measure vaccine effectiveness, the booster, mRNA-1273.214, raised virus-neutralising antibodies by eight-fold against Omicron.

Moderna has been studying the so-called bivalent vaccine, which targets both Omicron and the original coronavirus strain to determine if it works better against the variant.

Several studies have shown that vaccine immunity starts to wane over time, and the Omicron variant partially evades some protection from two doses.

"We anticipate more durable protection against variants of concern with mRNA-1273.214, making it our lead candidate for a Fall 2022 booster," said chief executive officer Stephane Bancel in a statement.