Catalysis of the reaction: ATP + 4-diphospho-1D-myo-inositol (1,2,3,5,6)pentakisphosphate = ADP + 4,5-bisdiphosphoinositol-1D-myo-inositol (1,2,3,6)tetrakisphosphate, and ATP + 6-diphospho-1D-myo-inositol (1,2,3,4,5)pentakisphosphate = ADP + 5,6-bisdiphosphoinositol-1D-myo-inositol (1,2,3,4)tetrakisphosphate.
diphosphoinositol-pentakisphosphate 5-kinase activity