• In a controlled clinical trial of massive-dose vitamin A therapy for xerophthalmia, holo-retinol-binding protein (holo-RBP) response was related to baseline protein status. Corneal healing was more commonly delayed or transient in children with protein-energy malnutrition (PEM), despite the vast majority achieving holo-RBP levels incompatible with severe corneal destruction. Correction of PEM is essential to ensuring a sustained clinical cure, and repeated massive vitamin A therapy is advisable until that occurs.