Pharmacodynamic properties
The active ingredient is a semisynthetic substance, similar to the physiological mucopolysaccharides which are the basic components of cartilage. Revised: January 2015 AN: 01275/2014 Page 3 of 4 Polysulphated glycosaminoglycan (PSGAG) inhibits cartilage degrading enzymes (various glycanohydrolases and glycosidases), stimulates the proteoglycan synthesis and hyaluronic acid synthesis and thus increases the viscosity of the synovia.
Pharmacokinetic particulars
Following a single intramuscular dose of 500 mg per horse, PSGAG is very rapidly absorbed. At 2 hours after administration, maximum serum concentrations of on average 1.9 mg/litre were attained. Thereafter, the concentrations declined with a half-life of 3.9 hours. From 24 to 96 hours after administration, serum levels remained constant around 0.1 mg/litre PSGAG is readily excreted in urine In the synovial fluids, Cmax-values of about 0.3 to 0.4 mg/litre are observed at a Tmax of between 2 and 4 hours after dosing. These concentrations decline rapidly.
From data in other animal species it is deduced that PSGAG has affinity for cartilage. Concentrations in cartilage are higher than in synovial fluids or serum. PSGAG is metabolised by removal of the sulphate groups and depolymerisation of the mucopolysaccharide chain. It is excreted with the urine. Less than 1 % is eliminated in the faeces.