The NIH now recommends that high-risk infants—those with severe eczema, egg allergy, or both—should be introduced to (age-appropriate) peanut-containing foods at 4-6 months of age, as long as they have already started solid food.
The change in advice comes largely from the results of the 2015 LEAP study showing an 81% reduction in peanut allergy among high risk children with earlier introduction.
They also strongly recommend peanut specific IgE measurement and/or skin prick testing before introduction. This flow-chart they provided aims to help with clinical decision-making.
You can read more about the new NIAID Guidelines in their Summary for Clinicians.