A compound for use in a method for increasing the lifespan of red blood cells (RBC) in a patient with pyruvate kinase deficiency (PKD) who needs it comprising contacting blood with an effective amount of (1) a compound of formula I or pharmaceutically acceptable salt thereof； or (2) a pharmaceutically acceptable composition comprising a compound of formula I or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, wherein the pyruvate kinase deficiency is a pyruvate kinase R deficiency, wherein: W , X, Y and Z are each independently selected from CH or N； D and D1 are independently selected from a link or NRb； A is optionally substituted aryl or optionally substituted heteroaryl； L is a bond, -C (O) -, - (CRcRc) m-, -OC (O) -, - (CRcRc) m-OC (O) -, - (CRcRc) mC (O) -, -NRbC (S) -, or -NRbC (O) - (where the point of attachment to R1 is on the left side)； R1 is selected from alkyl, cycloalkyl, aryl, heteroaryl and heterocyclyl； each of which is substituted with 0-5 occurrences of Rd； each R3 is independently selected from halo, haloalkyl, alkyl, hydroxyl and -ORa, or two adjacent R3 taken together with the carbon atoms to which they are attached form an optionally substituted heterocyclyl； each Ra is independently selected from alkyl, acyl, hydroxyalkyl and haloalkyl； each Rb is independently selected from hydrogen and alkyl； each Rc is independently selected from hydrogen, halo, alkyl, alkoxy and haloalkoxy or two Rc taken together with the carbon atoms to which they are attached form an optionally substituted cycloalkyl； each Rd is independently selected from halo, haloalkyl, haloalkoxy, alkyl, alkynyl, nitro, cyano, hydroxyl, -C (O) Ra, -OC (O) Ra, -C (O) ORa, -SRa, -NRaRb and - ORa, or two Rd taken together with the carbon atoms to which they are attached form an optionally substituted heterocyclyl； n is 0, 1 or 2； m is 1, 2 or 3； h is 0, 1, 2； and g is 0, 1 or 2.Un compuesto para uso en un método para aumentar la vida útil de los
