RESUMO
Eighteen out of 27 lots of fuenzalida & palacios type antirabies vaccine for human use produced at the Butanta, were filteres through two different Millipore systems, i.e., couple of cartridges (pre-filter & cart ridge of 0.55 aem porosity) or sandwich of membranes (pre-filter & membranes of 5.0 & 1.2 aem porosity). Afterwards, a study on the stability of the lots carried out during 18 months of storage at 2-8§C has demonstrated that filtration: a) reduced the protein contents of the vaccine, b) decreased the number of ampoules discarded due to the formation of clumps, c) didn`t interfere with the stability of the vaccine. It was also shown that combination of membranes was more suitable than cartridges for the filtration of vaccine lots and did not turn production costlier