The present invention provides pravastatin sodium substantially free of pravastatin lactone and epiprava, the C-6 epimer of pravastatin. The present invention further provides a novel process for recovering pravastatin sodium from a fermentation broth in such high purity. The process includes the stages of forming an solution of the compound by extraction, obtaining an ammonium salt of pravastatin from the solution, purifying the ammonium salt of the compound and transposing the salt of the compound to pravastatin sodium.