Most of a four-roomed maisonette on the ground floor of the building was damaged by fire. One woman and a baby were taken to hospital by London Ambulance Service crews.
Station Commander Leon Back, who was at the scene, said: “Crews very quickly gained access to the property and rescued a woman who was inside a maisonette on the ground floor.
“Crews worked extremely hard and professionally in very challenging conditions. The woman was taken to hospital along with a baby who was in the flat above.”
The Brigade was called at 3.28am and the fire was under control by 4.05am. Six fire engines and around 40 firefighters from Leyton, Leytonstone, Walthamstow, Stratford and Homerton fire stations attended the scene.
The cause of the fire is under investigation and being overseen by the Police.