Moderna says COVID-19 vaccine performed well in a small lab study against delta variant

Moderna's COVID-19 vaccine performed well in a lab setting against variants of the virus, including the rapidly spreading and highly contagious delta variant first found in India, the company announced Tuesday.

The mRNA vaccine produced neutralizing antibodies after two doses against delta as well as the beta and eta variants first found in South Africa and Nigeria, respectively, according to Moderna.

The vaccine did not perform as well against certain versions of the South African beta variant relative to the ancestral strain.

The data, which has not been peer reviewed, used serum samples from eight participants obtained one week after participants’ second dose of the company's primary COVID-19 vaccine. However, the results came from lab testing and may not reflect how effective the vaccine performs in the real world.

“As we seek to defeat the pandemic, it is imperative that we are proactive as the virus evolves. These new data are encouraging and reinforce our belief that the Moderna COVID-19 vaccine should remain protective against newly detected variants,” Moderna CEO Stéphane Bancel said in a statement. 

The announcement comes on the same day Moderna said its vaccine had been granted emergency use authorization in India, where the delta variant is thought to have fueled a massive outbreak. ..