Andre joined the Club from Fenerbahce in August.
The Brazilian left-back arrived at Emirates Stadium from Super Lig champions Fenerbahce, for whom he made 52 league appearances and scored 10 times. Santos supplanted Roberto Carlos as the team’s first choice left-back in his first season in Turkey.
He received his first senior cap for Brazil at the 2009 Confederations Cup - a tournament his country went on to win.
Arsène Wenger said: “Santos is a quality player, with the ability to both defend well and get forward and help with attacks.
“He has experience in the Champions League and for Brazil and has proved he can deliver at the highest level. We welcome Santos to the Club and look forward to him having a big impact for us.”
