ADMET

Aqueous Solubility

• Kinetic
• Thermodynamic
• Biorelevant media (FaSSIF and FeSSIF)

Lipophilicity (Log D and Log P)

• Octanol-water/phosphate buffer partitioning

Stability

• Simulated Gastro Intestinal fluids (SGF, SIF)
• Biorelevant media (FaSSIF and FeSSIF)
• Aqueous buffers at different pH
• Plasma and blood stability
• Dosing formulation

Pre-formulation

• Topical formulations
  • Creams/ointment/gel

1. Metabolic stability/ intrinsic clearance
   • Liver and intestinal microsomes
   • S9 fractions
   • Hepatocytes
   • Direct glucuronidation in liver microsomes using UDPGA
   • Reactive metabolites identification using GSH trapping assay
   • Metabolite finger printing analysis in liver microsomes
2. Metabolism based drug-drug Interactions
   • CYP inhibition (single point, IC₅₀) using human liver microsomes (HLM)
   • Time dependent CYP inhibition in HLM (IC₅₀ shift, K_i and K_inact)
   • CYP reaction phenotyping (purified rCYPs/microsomes)
   • CYP induction in plateable human hepatocytes
     1. 1A2, 2B6 and 3A4 enzyme activity
     2. mRNA analysis
     3. Cytotoxicity

• Intrinsic permeability-PAMPA
• Mono and bi-directional transport: CaCo-2 and MDCK cells
• In presence and absence of efflux drug transport inhibitors (P-gp, BCRP and MRP)

• Definitive plasma protein binding
• Microsomal protein binding
• Brain tissue binding
• Blood-to-plasma concentration ratio (RBC partitioning)

Cytotoxicity

• HepG2 cell line
• Hepatocytes

Rodents and non-rodents

• • Rats (multiple strains) : healthy and disease models
  • Mouse (multiple strains) : healthy and disease models
  • Beagle dogs: preferred vendor
  • Various routes of administration
  • Single, multiple and cassette dosing
  • Dose proportionality studies
  • Routes ( urine and feces) of excretion

Tissue exposure kinetics in rodents

• • Exposure kinetics in skin, plasma and other organs  (liver, spleen, thymus etc., ) of choice
  • Partitioning into brain (frontal cortex, striatum, hippocampus and cerebellum)
  • Cerebrospinal fluid collection
  • Partitioning into ocular and related parts (vitreous humor, retina and sclera)-rat

Dermal pharmacokinetics in rodents

• • Healthy and disease models
  • Assistance in selection of  right  animal model

Mechanistic pharmacokinetics models in rodents

• Chronic bile duct cannulated rats
• Chronic portal vein cannulated Rats
• ABT treated mouse and rat pharmacokinetics to delineate involvement of CYP enzymes

PK-PD, modelling and simulations (WinNonlin approach)

• • PK-PD/efficacy correlation – exposure or C_max based
  • PK modelling  and simulations (fit for purpose)
  • Scaling of  preclinical PK to predict human PK – allometry approach
  • Prediction of starting and efficacious human doses

High-throughput bio-analysis

• Fit for purpose methods
• 96 well plate analysis
• Cassette analysis

Quantitation of biomarkers

• Quantitative determination for biomarker modulations in plasma and tissues
• Expertise in quantitation of neurotransmitters and endogenous compounds
• Expertise in chemical derivatization techniques to improve chromatographic behavior and enhance ionization efficiencies

Biotransformation

• Soft spot analysis to drive structure-activity relationship (SAR) and facilitate in design of metabolically stable analogues
• Metabolite finger printing analysis
• Reactive metabolite screening (glutathione conjugation)

Trouble shooting expertise / assessment of matrix effects

• Evaluation of formulation excipients
• Evaluation of extraction methods
  • Protein precipitation
  • Liquid-liquid extraction
  • Solid phase extraction
• Evaluation of ionization polarity   (positive/negative)
• Evaluation of ionization source (ESI/APCI) technique of analysis (LC-MS/HPLC)

Miscellaneous

LC-MS/MS based in vitro primary and secondary activity screening

• Biological assays
• Complex lipid based assays