The former Edinburgh player initially joined Saints on loan in 2023 on a season long but made it a permanent move for the 2024/25 campaign.
Scottish-qualified through his father who hails from Ayr, Savala made the move from Australia to Edinburgh in 2020.
In March 2023, Savala was called up to the Scotland international squad for the final round of the Six Nations Championship.
Comfortable across the back-line, Savala scored three tries in 15 appearances for the Saints since his move to the Gallagher Premiership side.
Savala began his rugby journey in rugby league, starting out in the Sydney Roosters academy system before switching to the 15-a-side code.