Moderna begins trial for Omicron-specific booster shot

Moderna Inc on Wednesday said that it had started a mid-stage study, testing a booster dose specifically designed to target the Omicron variant of the virus, a day after rival Pfizer Inc launched a similar trial.

The company said while the third shot of its original coronavirus vaccine increased neutralizing antibodies against the variant at the lower dose, their levels declined six months after the booster dose was administered.

However, neutralizing antibodies remained detectable in all participants, Moderna said.

While studies have indicated that Omicron results in a less severe COVID-19 than seen during previous waves, the variant has quickly become dominant in many parts of the world, driving up infections and straining healthcare systems.

The variant currently accounts for 99.9 percent of the COVID-19 cases in the United States.

Pfizer and its partner BioNTech started a clinical trial on Tuesday to test a new version of their vaccine specifically tailored to the Omicron variant.

Moderna said it would study its Omicron-specific booster in adults aged 18 years and older.

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