Pravastatin (PRV), a lipid-lowering medication, is prescribed
to
treat cardiovascular disease and dyslipidemia. Due to its low permeability
and high solubility, the biopharmaceutics classification system (BCS)
class III drug exhibits poor bioavailability. To overcome the bottlenecks
of PRV, novel complexes with Zn and Cu along with a zwitterionic cocrystal
with l-proline (PRO) were synthesized. These new solid forms
were characterized by SC-XRD, PXRD, DSC, TGA, FT-IR, DVS, and SEM
images. Rietveld refinement was used to obtain the 3D coordinates
of the PRV–Na–PRO ionic cocrystal hydrate from high-resolution
PXRD data. PRV–Cu and Zn complexes were obtained by substituting
PRV sodium salt with a Cu/Zn metal. In PRV–Na–PRO cocrystal
hydrate, each Na metal is coordinated from carboxylates of PRV (2)
and zwitterionic PRO (1) and three water molecules result in an octahedron
geometry. Cu is coordinated with two carboxylate anions of PRV (2)
and three water molecules, forming a square pyramidal geometry. The
PRV–Zn complex maintains an octahedral geometry using four
coordination from two carboxylate anions of PRV (2) and two water
molecules. The PRV–Na–PRO cocrystal hydrate exhibited
higher solubility (1.7-fold) and diffusion profile (1.1-fold) compared
to the commercial PRV–Na salt hydrate, whereas PRV–Cu/Zn
complexes showed controlled drug release. Surprisingly, the PRV–Na–PRO
cocrystal hydrate enhanced peak plasma concentration C
max (50 fold) and AUC (14.4 fold) compared to the commercial
PRV–Na salt during pharmacokinetics study in rats. The stability
of the PRV complexes was supported by ground-state optimization energy
calculations. Unlike the moisture-sensitive PRV–Na salt hydrate
and PRV–Na–PRO cocrystal hydrate, PRV–Zn/Cu complexes
exhibited far superior moisture stability and may offer extended drug
release. On the other hand, the PRV–Na–PRO cocrystal
hydrate with significantly improved bioavailability can be commercialized
following proper formulation that offers moisture stability.