Covaxin has good phase III trial data and works against Delta!
This is an inactivated whole coronavirus vaccine produced by Bharat Biotech in India. This is traditional vaccine technology. The Polio vaccine is an inactivated whole virus vaccine. These vaccines are generally well-tolerated and since they are inactivated they are safe in the immunocompromised.
The other two inactivated whole coronavirus vaccines that are available are Sinopharm and Sinovac from China.
All three are fairly similar. They come in two doses and only need basic refrigeration. They all use aluminum hydroxide based adjuvants to boost the immune responses. Covaxin however uses Alhydroxiquim-II as an adjuvant which was developed by NIH's NIAID, as well as another adjuvant imidazoquinolinone. In addition, Covaxin uses the "European" strain with the D614G mutation that stabilizes the spike protein.
The primary phase III endpoint was symptomatic Covid. Overall efficacy against symptomatic Covid was 77.8%. Against severe Covid, efficacy was 93.4%. Against asymptomatic infection, efficacy was 63.6%. Most importantly against Delta efficacy was 65.2%. So this vaccine still holds up well against Delta.
Overall, another good vaccine candidate that will be an important part of global vaccination.
Link to study: https://www.medrxiv.org/content/10.1101/2021.06.30.21259439v1.full