American biotechnology company Moderna said on 29 June that its COVID-19 vaccine showed promise in a lab setting against coronavirus variants, including the highly contagious Delta variant first identified in India.

The results came from in vitro neutralisation studies of sera from eight participants one week after they received the second dose of the Moderna COVID-19 vaccine, the Xinhua news agency reported. The vaccine produced neutralising titers against all variants tested, including additional versions of the Beta variant, scientifically named B.1.351 which was first identified in South Africa; three lineage variants of B.1.617 which was first identified in India, including the Kappa (B.1.617.1) and the Delta variant (B.1.617.2); the Eta variant (B.1.525) which was first identified in Nigeria; and the A.23.1 and A.VOI.V2 variants first identified in Uganda and Angola, respectively, according to Moderna.

"This new data is encouraging and reinforce our belief that the Moderna COVID-19 vaccine should remain protective against newly detected variants," said Chief Executive Officer of Moderna Stephane Bancel. These data were submitted as a preprint to bioRxiv, and have not yet been peer-reviewed.