Sociedad signed Savio from Flamengo in a deal worth around £350,000.
Savio said: “I hope the fans can show a little patience as I haven’t played since December. It will take a little time for me to reach the required fitness levels.
“I’m here with great ambition. I’m used to competing for trophies and this is a different challenge. I had to think about this move, but I’m very happy to be here.”