The Islamists in this case are known as the Islamic Front, and it has not been defeated. Islamic Front has exactly the same goals for Syria as Islamic State, but it hasn't perpetrated acts of terror in other countries, at least as yet. Therefore they're not currently listed as a terrorist organization like Islamic State, al-Nusrah Front, etc.

The Islamic State still holds a large territory to the west of Aleppo, including the major city of Idlib. It's likely that they would meet the same fate as they did in east Aleppo if they choose to fight. Hopefully they will realize that and come to the negotiating table.