CY 222

CY 222 is a second-generation, very low molecular weight heparin (VLMWH) fragment with a mean molecular weight of approximately 2500 daltons. Developed by Choay Laboratories (now part of Sanofi), it is characterized by a significantly higher ratio of anti-factor Xa to anti-factor IIa (thrombin) activity compared to standard low molecular weight heparins (LMWHs), often exceeding 10:1 or even 20:1. This high selectivity is attributed to its short polysaccharide chains, which contain the essential pentasaccharide sequence required to catalyze the antithrombin-mediated inhibition of factor Xa but lack the chain length (typically 18 saccharide units) necessary to simultaneously bind both antithrombin and thrombin. CY 222 has been clinically evaluated for the prevention and treatment of deep vein thrombosis (DVT) and for anticoagulation during hemodialysis, where its specific pharmacokinetic profile—including a longer half-life and reduced clearance in patients with chronic renal failure—requires careful dose adjustment.

Other names

Very low molecular weight heparinVLMWHUltra-low molecular weight heparinULMWH