Moderna study shows waning immunity for COVID shots, supports booster

Pharmaceutical group Moderna said a study of breakthrough COVID-19 cases among vaccinated individuals supports the need for a booster shot. In a news release on Wednesday, Moderna identified 88 breakthrough COVID cases among 11,431 people vaccinated between December 2020 and March 2021, but 162 cases in the group who got their shots between July and October of last year. The vaccine maker also noted a lower incidence of severe cases among those recently vaccinated. "This is only one estimate, but we do believe this means as you look toward the fall and winter, at minimum we expect the estimated impact of waning immunity would be 600,000 additional cases of COVID-19," said Moderna President Stephen Hoge on a news conference. Pfizer on Wednesday also said its own clinical data indicated those vaccinated who are 16 and older shoud get a booster after six months. On Friday, an independent advisory committee to the Food and Drug Administration will discuss and vote on whether the agency should approve boosters for that age group. Moderna shares were slightly higher in premarket trade on Thursday, while Pfizer stock was unchanged.

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