Embryo-fetal loss data (EFL, between gestation day [GD] 20 and 140) and stillbirth (SB, after GD140) were compared in the Cynomolgus monkey model between our “old” historical control data, obtained from 18 pre- and post-natal developmental (PPND) studies (N=341 at GD20) conducted in 2005 – 2011, and currently on-going in-house (“new”) PPND study (N=11).
All maternal animals in the old data were single-housed and socially-housed (two animals in a four-pack caging unit) in the new data set. Total number of EFL was 18.2% (mean ±SD = 18.1 ±8.7%, Min to Max = 6.3 to 31.3%) in the old data and 9.1% in new data sets. Incidences in the first, second, and third trimesters (GD20 – 50, 51 – 100, 101 – 140) were 12.9, 2.9, and 2.3%, respectively, in old data set and 0.0, 0.0, and 9.1%, respectively, in new data set. Mean gestation length was 158 ±8 days in old data and 159 ±7 days in new data set.
Total number of SB was 14.7% (mean ±SD = 14.4 ±9.3%, Min to Max = 0.0 to 33.3%) in old data and 0/10 (0.0%) in new data sets. Total number of infant death at on or before Day 7 of post-birth was 4.8% (mean ±SD = 4.9 ±5.3%, Min to Max = 0.0 to 14.3%) in old data and 0/10 (0.0%) in new data sets.
Common clinical pathology data collected during the gestation period and during the first month post-delivery were also comparable between the two data sets. Although numbers of data points from socially-housed animals are still small at this point, EFD/SB data, and common clinical pathology parameters, obtained from socially-housed animals, were comparable with those obtained from single-housed animals. Therefore, we consider that both data sets can be combined and historical control data in PPND studies can be accumulated further despite variances in housing conditions.
S. Oneda, N. Lalayeva, J. Reynolds, G. Von Scherr, M.Vegarra, T. Rogers.
SNBL USA, Ltd., Everett, WA, USA