In vitro behaviour of the enteric-coating of a new pancreatic enzyme containing preparation in enteric-coated microtablets was evaluated, by incubating at 37 degrees C, under gentle agitation, the preparation under study in buffered gastric (pH 2, 3, 4, 5, 6) and in buffered duodenal juice (pH 3, 4, 5, 6, 7, 8) for 30, 60, 90, 120 minutes. Lipase and chymotripsin activities were measured at each time and pH in the solution and in the undissolved microtablets. The drug under study showed a good enteric-coating, preserving about 100% of the enzyme content, when incubated in buffered gastric juice, up to pH 6, and releasing in the solution, during incubation in buffered duodenal juice, 75% of its enzyme content at pH 7 and 8. Therefore, the pancreatic enzymes contained in this new enteric-coated microtablet preparation are well protected against inactivation from acid and are bioavailable for digestion of alimentary substrates at optimal or near optimal pH in duodenal juice.