Per Zak Keefer of the Indianapolis Star, Lewis is expected to miss nine weeks as he recovers.
Colts head coach Frank Reich addressed Lewis' status while talking to reporters on Monday.
"Not right now," Reich said when asked if Lewis was close to returning. "No surgery, just hasn't been coming along as fast as we would've liked. No, we are hopeful we will have him. We're hopeful we will have him."
Lewis was the Colts' second-round pick at No. 64 overall. He hasn't appeared in any of the team's first three preseason games due to the injury.
Andrew Walker of Colts.com noted on June 7, the ninth day of organized team activities, that Lewis wasn't in action during the portion of practice open to the media.
The Colts' depth chart lists Lewis behind Denico Autry as one of the two utility tackles on the defensive line. Hassan Ridgeway and Brandon Banks are competing for the third-string spot.
Lewis, 23, played four seasons at Ohio State from 2014-17. He recorded 37 tackles for loss and 23.5 sacks in 44 college games.
A nine-week absence for Lewis would allow the Colts to put him on injured reserve with the designation to return.
Indianapolis kicks off the 2018 regular season on Sept. 9 against the Cincinnati Bengals.