The trials, were directly supervised by the Butantan institute a very reputable research center in Brazil. I also know of someone in Brazil following the program. Brazil has many problems but one thing they do well -- vaccination. Excellent programs due to decades of experience dealing with infectious diseases. Won't be surprised is they finish vaccinating their entire population before Argentina in the end.
News from the neighbors regarding the sinovac vaccine - apparently only 50.4% effective but at least appearing to reduce the severity of the illness in the other 50%.
“There has been concern and criticism that Chinese vaccine trials are not subject to the same scrutiny and levels of transparency as its Western counterparts.”