Biopharmaceutics of intrathecal baclofen-loaded microparticles in a goat model

The catheter was well tolerated and did not interfere with behavioral testings. Baclofen CSF clearance (mean = 8.59 ± 2.43 ml/h) and volume of distribution (21.06 ± 13.32 ml) were not significantly affected by the increase of the dose (p > 0.05). In vivo, the baclofen levels in CSF were stabilized at 200 μg/l after a period of 3 days. The predictive value of the in vitro release studies was good since the theoretical levels ranged between 128 and 257 μg/l. In conclusion, a large animal model was developed and allowed the biopharmaceutic evaluation of baclofen microparticles injected via intrathecal route.