Embryo fetal development studies in nonhuman primates.

Area of Science:

• Primate reproductive toxicology
• Embryo-fetal development (EFD) research
• Pharmaceutical safety assessment

Background:

• Nonhuman primates, particularly Macaca fascicularis (cynomolgus monkeys), are standard models for embryo-fetal development (EFD) studies.
• Recent guideline updates (ICH M3(R2), S6(R1)) have shifted EFD study focus towards conventional pharmaceuticals over biopharmaceuticals.
• Marmosets are also a viable species for conducting EFD studies.

Purpose of the Study:

• To provide standardized protocols for conducting embryo-fetal development (EFD) studies in nonhuman primates.
• To detail methods for collecting, processing, and examining fetuses, including amniotic fluid and umbilical cord blood.
• To establish consistent terminology for external, visceral, and skeletal fetal examinations.

Main Methods:

• Detailed protocols for fetus collection, preservation, and staining.
• Procedures for amniotic fluid and umbilical cord blood collection.
• Standardized methodologies for external, visceral, and skeletal examinations of primate fetuses.

Main Results:

• Established working protocols for EFD studies in cynomolgus monkeys and marmosets.
• Defined terminology for consistent reporting of fetal abnormalities.
• Guidance on adapting EFD studies for current pharmaceutical regulatory requirements.

Conclusions:

• Cynomolgus monkeys and marmosets are suitable models for conducting embryo-fetal development (EFD) studies.
• Standardized protocols and terminology are crucial for reliable EFD study outcomes.
• The presented methods support regulatory compliance for pharmaceutical development.