In 2018, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) concluded that whey basic protein isolate obtained by ion exchange chromatography from skimmed cow's milk is safe for human consumption under the proposed conditions of use as infant and follow on formula, meal replacement beverages, foods for special medical purposes and food supplements. Following a request from the European Commission, the EFSA NDA Panel was asked to deliver a scientific opinion on whey basic protein isolate for extended uses in foods for special medical purposes and food supplements for infants as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The applicant seeks to extend the conditions of use to infant (powder 30 mg/100 g and reconstituted 3.9 mg/100 mL) and follow on formulae (powdered 30 mg/100 g and reconstituted 4.2 mg/100 mL) as foods for special medical purposes as well as in food supplements for infants (25 mg/day). The Panel considers that the proposed extended uses would not increase the potential intake of the NF compared to that assessed in its 2018 opinion. The Panel concludes that whey basic protein isolate is safe at the extended uses and use levels.