Four fire engines and around 25 firefighters were called to a fire at a block of maisonettes on Rogers Road, Canning Town.
Part of a maisonette on the third floor was damaged by fire. Two people left the building before the arrival of the Brigade and were treated at the scene for smoke inhalation before being taken to hospital by London Ambulance Service crews.
The Brigade was called at 0037 and the fire was under control at 0210. Fire crews from Plaistow, Poplar, East Ham and Stratford fire stations attended the scene.
The cause of the fire is under investigation by the Brigade.