A booster dose of Sinovac Covid-19 vaccine following a two-shot regimen does not offer adequate protection against the fast spreading Omicron variant, a laboratory study has found. The study was conducted by a team of researchers from the University of Hong Kong and the Chinese University of Hong Kong, reported Reuters. The number of samples used in the study was not disclosed. The study also found that Pfizer-BioNTech vaccine was more effective in neutralising the Omicron variant.

The South African Health Products Authority (SAHPRA) has approved Covid-19 vaccine Janssen (Ad26.COV2.S) as a second dose or a booster following an assessment of safety and efficacy data. According to a SAHPRA statement, the Janssen vaccine can be administered as a booster shot minimum two months after primary vaccination with an approved mRNA vaccine. The authorisation comes after Janssen submitted an application earlier this month requesting an amendment in the dosing schedule for Janssen vaccine.

Novavax and SK bioscience have agreed to expand their collaboration and licence agreements for the former’s recombinant nanoparticle protein-based Covid-19 vaccine NVX-CoV2373. As agreed, SK bioscience will reserve additional manufacturing capacity to produce antigen, a key component of NVX-CoV2373 through next year. The arrangement may be extended in future. Previously, SK bioscience signed an advance purchase agreement (APA) to deliver 40 million doses of NVX-CoV2373 for South Korea.