The 21-year-old midfielder, who attracted interest from some of the big clubs in England over the summer, has been kept to substitute appearances so far this season.
Howe said: "Going back to before the first game, we picked the team, basically, that we had against Marseille where we produced a really good performance.
"I didn't want to deviate from that team for the first game and Lewis has fallen victim to that. He will have a big part to play this season, I have no doubt about that.
"He has come on in games and done well and played in the Carabao Cup, which was good to see.
"We have a very strong unit in central midfield and have some very good players all competing for two places. Lewis has a big future ahead of him."