But Ospreys head coach Sean Holley believes the tight-head will be fit in time to welcome the French side to the Liberty Stadium this weekend.
"Adam has trained really well and there are positive signs," Holley told the South Wales Evening Post.
"I don't want to excite myself too much but the signs are good for an involvement next week.
"Adam has had his own training programme, done a little bit of running and done a lot of work with Mark Bennett on conditioning to make sure he doesn't lose any of that work he did in the summer.
"He did his first one-man scrummaging on Friday and came through pretty good.
"In his stage of rehab he couldn't be in a better position. He is on target. Let's see how it goes over the next five or six days."