Rite Aid, the No. 3 pharmacy that will soon merge with Walgreens Boots Alliance, said its December same-store sales edged down 0.1%. The drugstore chain, which operates more than 4,500 stores, said pharmacy comparable sales dipped 0.6%, and prescription count comps fell 0.4%, while front-end comps rose 0.8%. Total drugstore sales for the four weeks ended Dec. 26 were flat, year over year, at $2.2 billion. On Dec.