Sanofi on Friday announced the launch of human trials of its second Covid-19 vaccine, with its first still in the testing phase after having fallen behind in development.Sanofi and US company Translate Bio are developing the vaccine based on messenger RNA technology.Also Read | Vaccine confidence in India is ticking more boxes nowThe phase 1 and 2 trials aim to verify that the vaccine is not dangerous and to provide initial information on its effectiveness.Phase 3 would be carried out on many more patients to determine its effectiveness.The first trials will include 415 people, with inital results expected in the third quarter.Messenger RNA technology is also used in the Pfizer/BioNTech and Moderna vaccines, already authorised in the.