sn-Glycero-3-phosphocholine-d 9 is the deuterium labeled sn-Glycero-3-phosphocholine. sn-Glycero-3-phosphocholine (Choline Alfoscerate) is a precursor in the biosynthesis of brain phospholipids and increases the bioavailability of choline in nervous tissue. sn-Glycero-3-phosphocholine (Choline Alfoscerate) has significant effects on cognitive function with a good safety profile and tolerability,and is effective in the treatment of Alzheimer's disease and dementia.