Sanofi, GSK Push Back Full COVID-19 Booster Study Results

Sanofi and GlaxoSmithKline (GSK) said preliminary data from a phase 3 study showed that a booster dose of their experimental COVID-19 shot induces strong immunity but said they won’t release full trial results until early next year.

The companies attributed the delay to needing more time to evaluate the booster in participants who haven’t been infected with the coronavirus ― a delay suggested by the independent data and safety monitoring committee. The drugmakers had previously said they hoped to gain regulatory approval by year’s end.

The preliminary results indicate that a Sanofi/GSK booster increased neutralizing antibodies by up to 43-fold, regardless of which vaccines participants originally received. The booster was given to trial participants four to 10 months after completion of a primary regimen with either the AstraZeneca, Johnson & Johnson (J&J), Moderna or Pfizer/BioNTech shots.

The protein-based adjuvanted vaccine is also being assessed for efficacy in a primary vaccination series. Sanofi and GSK launched the phase 3 study in May after being forced to reformulate the shot because it provoked an insufficient immune response in older adults (DID, Aug. 4). ― Jason Scott