This document discusses tier 2 safety pharmacology studies, which assess potential adverse effects on organ systems not addressed by core battery studies. It focuses on methods used to evaluate drug effects on renal and gastrointestinal systems. For renal evaluation, in vivo mammalian models are commonly used to measure glomerular function via clearance tests and tubular function via urine analysis. Hemodynamic effects are also assessed. In vitro, non-mammalian, and in silico models provide additional methods. Gastrointestinal evaluation involves tests like barium meals and pylorus ligation, as well as emerging endoscopic, biomarker, and electrophysiological techniques.

1. SAFETY PHARMACOLOGY
STUDY
TIER 2
SUBMITTED BY: SUBMITTED TO:
GAJENDER DR SAUMYA DAS
M.PHARMA (PHARMACOLOGY) (ASSISTANT
PROFESSOR)
1ST YEAR NIET (PHARMACY
INSTITUTE)

2. TIER 2 SAFETY PHARMACOLOGICAL
STUDIES
 Also called as supplemental pharmacological studies.
 Used to access potential adverse pharmacodynamic effect on organ
system function not addressed by core battery studies.
 It includes
Renal/Urinary system
Gastrointestinal system
Other organ system
• Skeletal system
• Immune and endocrine functions

3. RENAL STUDIES IN SAFETY
PHRAMACOLOGY
The kidney is a complex excretory organ
Playing role in
Fluid and electrolyte balance
Control of blood pressure
Removal of waste product
Drug disposition
Endocrine function

4. RENAL STUDIES IN SAFETY
PHARMACOLOGY
30-40% drugs invented can cause
renal injury
Still the safety pharmacological
studies related to renal system in
preclinical system is small.

5. METHODS TO ACCESS DRUG EFFECTS ON RENAL
FUNCTION
It should cover
Excretory function
Hemodynamic function
Endocrine aspects
In-vivo models are frequently used.

6. MODEL EMPLOYED
In-vivo mammalian model
Glomerular function
Tubular function
Hemodynamic function
In-Vivo Non Mammalian models
In-Vitro models
In-Silico model

7. IN-VIVO MAMMALIAN
MODEL
 Rats , Dogs, Pigs are commonly used
 Conscious , freely moving animals
 Analysis of urine and plasma are done
 Urinary bladder catherterization and metabolism cage
are used

9. 1. GLOMERULAR FUNCTION
Clearance measurement of endogenous and exogenous small
molecules ( ureas , creatinine , 2-MPT, insulin, cystatin c,
iohexol , or indixanol )
Analysis of plasma and urine samples
The noninvasive clearance(NIC)- kidney device that when
mounted on the back of laboratory animals enables the
transcutaneous measurement of the elimination kinetics of the
fluorescent renal markers FITC-sinistrin
This allows the measurement of the clearance of FITC-sinistrin
from the plasma in real time without the need for any blood
sampling

10. 2. TUBULAR FUNCTION
• Allows the identification of the functional status of the
particular nephron segments
• Includes visual assessment of urine (colour, clarity), volume ,
specific gravity or osmolarity, pH, quantitative or
semiquantitative protein, and glucose content
• Dipstick test strips assess other parameters such as ketones,
bilirubin, urobilinogen, hemoglobin etc

11. HOW TO INTERPRET A URINE DIPSTICK

12. 3. HEMODYNAMIC FUNCTION
1. Direct renal blood flow measurement
• Require the placement of a flow probe arounds the renal artery
• Conducted in large animal species such as dogs, pigs, and non
human primate
• Usually coupled with systemic species such as dogs pressure
monitoring using a pressure catheter placed inti an artery
• Another hemodynamic endpoints is the renal vascular resistance(RVR)
calculated as the ratio between RBF and mean arterial pressure (MAP)
• RVR can be increased in case of renal dysfunction or in case of
systemic hypertension

13. 2. INDIRECT RENAL
BLOOD FLOW
MEASUREMENT
Para- aminohippuric acid
(PAH)clearance test
All PAH passing through the kidney
appears in the urine
PAH clearance is directly
proportional to the rate of plasma
flow through the kidney
If the hematocrit is known, the total
renal blood flow can be easily
calculated from the eRPF value

14. IN VIVO NOM MAMMALIAN MODEL
• The zebrafish (danio rerio) larva has gained increasing interest over
the last decade as an alternative to mammalian in vivo models
• The zebrafish kidney is genetically and morphologically closed to the
mammals
• Measurement of FITC insulin intensity in the caudal artery and
excreted FITC insulin
• Validated using gentamicin and high salt loading
• High throughput screening visual transparency low cost and genetic
manipulation

15. IN VITRO MODELS
• In vitro model complex composed of a filter unit and a tubular segments
together containing over 20 different cell type
• Nephrotoxicants cause injury by selectively injuring specific cell type of by non
selective injuring multiple cell type with in the kidney , depending on their
mechanism of action.
• Assessment of the potential nephrotic effect of pharmaceutical compounds of
different model system
• In vitro model the recapitulates the in vivo response of renal cells to
nephrotoxicants requires appropriate expression of the transporters and
receptors that interact with the drug of interest
• In addition to detecting expression of transporters at the transcript and protein
level by quantitative PCR and immunohistochemistry, the function of
transporters and endocytic receptors can be investigated by assessing the effect
of fluorescent substrates and transport inhibitors

16. IN SILICO MODELS
• The SAPHIR project ( a system approach for physiological
integration of renal , cardiac, and respiratory functions initiated
in 2008
• Targeting the short and long term regulatory of blood pressure
and body fluid ,and homoeostasis of major solutes
• For renal and urinary disorders, the predictivity was not very
high

17. GASTROINTESTINAL SAFETY
PHARMACOLOGY
• 2-3 % discontinuation of drug project
• Related ADRs and AEs are not life threatening but hamper
quality of the life for patients
• 18%of total ADRs
• Overuse of NSAIDs in US is a reason behind >100000
hospitalization and 17000 details in a year(20030
• Hence there is a need for improved and more extensive GI
screening

18. EVALUATION METHODS
• Barium sulfate or a charcoal test meal
• Pylorus ligation
Emerging techniques
• Endoscopy
• Biomarkers
• EMG citrulline
• Mir-194
• calprotectin

20. THANK YOU FOR
LISTENING