Nonhuman primates embryofetal development

Because the type I interferons produced no adverse effects on embryofetal development and the early abortifacient effect could be predicted based on a measurement of female endocrine changes, the need to conduct additional macaque embryofetal development studies for type I interferons in nonhuman primates was considered unnecessary. Therefore, for the second-generation pegylated versions of the alpha interferons, only hormonal analysis was conducted in macaques. This is the only known example of where mechanistic studies have been accepted in place of developmental studies in accordance with ICH S6 guidance. 

TABLE 18.6 Parameters for evaluation of embryofetal development in the nonhuman primate model... 

For most biotherapeutics that do not cross-react with rodents or rabbits, an embryofetal development study in macaques is generally conducted during clinical development to support the inclusion of women of childbearing potential in clinical trials. However, postnatal development studies in nonhuman primates have not routinely been conducted. Consequently, the protocols and the end points are less well established for evaluation of postnatal effects on the immune system. 

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