Safety issues require that novel drugs and novel excipients, formulated in pH-dependent ileocolonic drug delivery systems, are tested in appropriate animal species before they are evaluated in humans. In a literature search, we found that, of the most frequently used laboratory animal species, the rabbit is the best choice. Its gastrointestinal (GI) pH values most resembles those in humans. In cases where rabbits cannot be used, pigs, dogs, and rats can serve as an alternative provided that GI pH values of individual animals are checked. Various methods to investigate the performance of ileocolonic drug delivery systems are available. We recommend testing novel drugs with non-invasive imaging techniques in combination with plasma sampling, whereas novel excipients are best tested with the theophylline-sulfasalazine method.

安全问题要求在依赖 pH 值的回结肠给药系统中配制的新药和新赋形剂在进行人体评估之前先在适当的动物物种中进行测试。在文献检索中，我们发现，在最常用的实验动物物种中，兔子是最佳选择。它的胃肠 (GI) pH 值与人类最相似。在不能使用兔子的情况下，猪、狗和大鼠可以作为替代品，前提是检查个别动物的 GI pH 值。有多种方法可以研究回结肠给药系统的性能。我们建议使用非侵入性成像技术结合血浆取样测试新药，而最好使用茶碱-柳氮磺吡啶方法测试新赋形剂。