The 49ers placed Carradine on injured reserve a few weeks into the regular season with a high-ankle sprain before designating him to return a few weeks ago.
Carradine, 27, is a former second-round pick of the 49ers back in 2013. He was in the final year of his four-year, $4.948 million rookie contract when he and San Francisco agreed to a one-year contract extension before the start of the 2016 season.
Carradine will make a base salary of $1.1 million this year before becoming an unrestricted free agent in 2018.
In 2017, Carradine has appeared in three games and recorded seven tackles and a sack.