After feeding three more vials of Blood Replenishing potion and a vial of Essence of Murlap, Hermione asked Cho to repeat those spells and show her how to cast them properly. Cho did, and they spoke the healing charms a few more times until Cho was satisfied with the result. Malfoy’s back was still ruined, and the runes would clearly leave awful scars for the rest of his life, but Hermione breathed out shakily, relaxing slightly when she was sure there was no more danger for him to die.