Vivaldi: Tweaking attenuation

Approved influenza vaccines have modest efficacy in patients aged 50 years and older, which comprises one of the most at-risk segments of the population. Vivaldi Biosciences Inc. hopes its NS1 deletion technology will allow it to attenuate viruses with more control, allowing it to develop a live attenuated vaccine with greater efficacy in this population.

According to CEO Douglass Given, inactivated flu vaccines approved for patients aged 50 and up are only about 30-40% protective against illness in the population and 60% effective at preventing death. He estimates that patients 50 and over make up about 80% of the seasonal influenza market...