We also have a range of species for testing target molecules. While a majority of the studies recommend using rats and dogs, other species can also be used if data suggests that they are more biologically relevant. For clients that prefer the use of non-rodent species, we offer preclinical studies which can be conducted in non-human primates such as minipigs.

Pivotal GLP tox study
A typical study design for pivotal GLP studies for rodents and non-rodents involves a dosing phase of 28 days, followed by a recovery phase of 14 days or 28 days. The rodents/non-rodents are divided into four groups (control, low dose, mid-dose, and high dose), each consisting of an equal number of males and females with standard observations/endpoints. Toxicokinetic is integrated into the pivotal GLP tox study. The parameters observed include morbidity and mortality (daily checks); pre and post-dose clinical signs (pre and post-dose); ophthalmic examination; bodyweight; food consumption; clinical pathology (main groups and recovery groups); necropsy and gross examination; histology of all organs including injection site(s), if any; dose formulation concentration analysis and bioanalysis and toxicokinetics.

Safety Pharmacological studies
We conduct Pharmacological studies using the Irwin test, Respiratory Function test, Cardiovascular Safety Pharmacology test, and in vitro hERG assays.

• Irwin test: We conduct this study to test the pharmacological effects of target molecules on the central nervous system in rodents. We use it to assess the functionality and toxicity of chlorpromazine, triadimefon, trimethyltin, and acrylamide. The test is also used to assess many bodily functions, such as respiratory pattern, mobility, gait, salivation, pupil reflex, and motor activity (Figure 2)

• Respiratory function test: A special plethysmograph chamber is used to assess the respiratory properties of rodents. The parameters monitored include Ti-inspiration time, Te-expiratory time, PiF-peak inspiratory flow, PeF-Peak expiratory flow, TV-Tidal volume, MV-Minute volume, F-Respiratory rate, RT-Relaxation time

• Cardiovascular safety pharmacology: Telemetry [Jacketed/Invasive] using non-rodents

• In vitro human Ether-a-go-go Related Gene (hERG) assay: Patch clamp

Biologics Studies
To test a target molecule in an animal model, we pay special attention to the following:

1. Selection of relevant animal species

   • Studies are done in relevant species, i.e., species that demonstrate pharmacological effects

   • With biologics, non-human primates (NHPs) are often the only relevant species available for testing

   • If a second species is relevant, we evaluate them as well

   • No relevant animal model other than transgenic strain expressing human receptor is considered for studies

2. Dose, route of administration, and treatment regimen

   • High dose, 10X over maximum exposure, tested to establish an adequate safety margin.

   • Route/frequency of administration kept the same as that proposed for clinical use

   • Conducting pivotal 28-day repeated dose toxicology study in relevant animal species

Vaccine Studies
Our vaccine study design comprises a 43-day dosing phase, followed by a 28-day recovery period. Animals are assessed for clinical pathology, organ weights, gross pathology, histology of organs, immunogenicity, local tolerance, and other clinical signs.

We also conduct vaccine prenatal developmental toxicity study design covering the following:

• Clinical signs, local tolerance, body weight, and food consumption

• Cesarean section: Gestation day 20

• Maternal data: Uterine weight, # corpora lutea, implantation sites, early and late resorptions, pre-and post-implantation losses

• Litter data: Total no. of fetuses (live and dead), litter weight, Sex ratio (M: F)

• Fetal evaluations: External, visceral, and skeletal malformations. Classified as normal variants, minor anomalies, and major malformations

• Immunogenicity: Prior to dosing and at termination