Toxicology studies and GLP-compliant pharm/tox services

Acquiescence with GLP Commercial Toxicology Services. Many commercial laboratories offer a full range of services, from exploratory programs to fully GLP-compliant toxicology studies. These services support establishing the toxicological profile of new compounds or further studying the known profiles of existing ones (new indications, formulations, routes of administration). The latter spans acute to chronic toxicity, with various species and dosage methods, mainly specialising in toxicology. These data are used to support human clinical studies and marketing authorization applications worldwide.

The goal of non-clinical animal research is to define safety margins for compound effectiveness and tolerable side effects for the examined medication candidates. General toxicological studies are often undertaken to determine how harmful an object or substance is to animals. The investigations are intended to define possible toxicity and assess the degree of no-observed-adverse-effects (NOAEL). Hundreds of successful IND filings clients have been backed by toxicology studies. All conventional dosage regimens and species, including primates, are supported, and GLP toxicity investigations are carried out in full accordance with GLP and animal welfare requirements.

The majority of laboratory facilities offer non-clinical safety assessment investigations in fields such as medicines, chemicals, medical devices, and food additives at a certain biosafety level (BSL-2). Many toxicologists adhere to the 3R (replace, reduce, refine) principles, using well-managed animals in a highly enriched habitat. Regardless of the goal (regulatory or non-regulatory), these laboratories undertake all research to the highest standards achievable. Toxicology services teams are made up of competent and trained scientists who have DABTs and DIBTP-certified pathologists. They are well-experienced in the field of toxicology and sophisticated technologies at the GLP test facility, and they are dedicated to the facility’s purpose of servicing worldwide demands in toxicology and biosafety.

GLP-certified laboratories should have restricted access. The GLP facility uses in silica, in vivo, and in vitro models to ensure the safety of appropriate products in the pharmaceutical, biotechnology, and life science industries. Many rodent facilities are built with a double corridor facility and dedicated experimental rooms equipped with Individually Ventilated Cages (IVC), and many are registered with the respective country’s ethical council. To maintain quality standards, laboratories are routinely audited by the US FDA and the National GLP Compliance Monitoring Authority (NGCMA), and procedures are extensively supervised by an independent Quality Assurance Unit (QAU).

Toxicology of chemicals can be studied by (a) investigating accidental exposures to a material, (b) conducting in vitro research employing cells/cell lines, and (c) exposing experimental animals in vivo. Many pharmaceutical services have demonstrated their ability to provide a variety of toxicological services in order to enable seamless integration between research and development programs.

GLP Certified Studies

1) Types of Chemicals/Materials for Toxicity Studies:

 Industrial chemicals  Agrochemicals  Pesticides  New chemical entities (NCE)  Pharmaceuticals (Small molecules, Biosimilars, Biotherapeutics, Vaccines and Recombinant DNA products, etc)  Cosmetics  Feed and Food additives  Nanomaterials  Medical devices  Biomedical implants  Veterinary drugs

2) Test Systems for the Studies:
 Rodent (mouse – Swiss albino; CD-1; SKH-1; C57BL/6; BALB/C, rat – Wistar, cotton rat, hamster, gerbil, guinea pig – Hartley)  Ferret  Rabbit – New Zealand White  Dog  Minipig  Nonhuman primate  Immunocompromised rodent  Aquatic and terrestrial organisms  Cell lines (WI-38, Y79, HeLa, CHO)

3) Routes of test compound administration:

 Oral (gavage using soft tubes, food/water)  Respiratory (Intratracheal, “Nose-only”)  Intravenous (Injection – bolus, Infusion – administration without immobilisation)  Subcutaneous (Injection, Implants with osmotic pumps)  Dermal  Intradermal  Intramuscular  Intraperitoneal  Nasal  Rectal  Multiple Dose Routes  Intracranial/Intracerebral  Intrathecal  Intraprostatic  Synovial  Intratumoral

4) Toxicology studies include:

General toxicology using rats/mice:

o Acute toxicity (LD50) o Acute toxicity testing for inhalation

o Repeated dose toxicity testing o Exploratory/Dose range finding (MTD)

o Sub-acute toxicity (14/28 Day) o Subchronic oral toxicity testing (90 day)

o Chronic oral toxicity testing (6/12 months)

o Drug impurity qualification studies o Skin sensitization tests using guinea pigs (Draize test, open epicutaneous test, optimization test, split adjuvant test, guinea pig maximization test (GPMT), Buehler test, and murine local lymph node assay (LLNA))

o Carcinogenicity testing

Reproduction Toxicity Studies:

o Fertility and reproductive toxicity in rats o Male fertility study

o One-generation reproduction toxicity testing

o Two-generation reproduction toxicity studies o Embryotoxicity studies (embryonic stem cell test (EST) for embryotoxicity, micromass embryotoxicity assay, and whole rat embryo embryotoxicity assay)

Genetic Toxicology Studies:

o Bacterial reverse mutation test (Ames test) o Mouse Lymphoma TK Assay o In vitro Micronucleus Assay

o In vitro Chromosome Aberration Test

o In vivo Rodent Micronucleus Assay

o Rodent Bone Marrow Chromosomal Aberration Test

o Pig-a Endogenous Gene Mutation Assay

Pharmacokinetics:

o Toxicokinetic using animals and in vitro cell line (area under the curve, drug distribution ratio, Cmax, tmax, etc.)

o PK Sample Analysis

o Metabolite Identification and Profiling o Rapid PK Screening o Mass Balance o Tissue Distribution

o Bioequivalence (formulation support) o MSD-ECLA (Meso Scale Discovery) Assays o ELISA Assays

Pharmacodynamics:

Only primary pharmacodynamic studies are completely free from GLP restrictions. Secondary pharmacodynamic investigations will be undertaken in accordance with GLP quality standards – Bioequivalence (formulation support)

o Pharmacodynamic (PD) biomarker method for monitoring of β-lymphocyte suppression (blood, bile, serum, plasma, urine, tumour cells, and skin tissues)

o Ligand binding methods o Semi-quantitative PD assay

o Chromatographic method o flow cytometry (FC) methods

o Commercial immuno-assay kits for PD analysis

Safety Pharmacology services:

Non-clinical methods are recommended for use in the safety pharmacology core battery of tests by ICH Guidelines. The circulatory, respiratory, and central nervous systems are commonly regarded as the essential organ systems that should be investigated in the core battery.

o Central Nervous System – behavioral pharmacology, learning and memory, ligand-specific binding, neurochemistry, visual, auditory, and/or electrophysiology examinations

o Cardiovascular System – cardiac output, ventricular contractility, vascular resistance, the effects of endogenous and/or exogenous substances on the cardiovascular responses

o Respiratory System – airway resistance, compliance, pulmonary arterial pressure, blood gases, blood pH

o In vitro Electrophysiology via hERG

Bioanalytical methods:

o GS, HPLC, LC and GC combined with mass spectrometric (MS) procedures such as LC-MS, LC-MS-MS, GC-MS, and GC-MS-MS.