GLP and animal toxicity for students.pptx

Details of animal toxicity and GLP

1. GOOD LABORATORY PRACTICE

2. Drug development process

3. PHASES OF DRUG DEVELOPMENT (ANIMAL MAN) PHASE III PHASE IV PHASE I PHASE I PRECLINICAL PHASE II Product Approval (NDA/MAA) Patient studies Entry to man (IND / CTA) None Healthy subjects Safety and tolerability Genetic toxicity (in vivo) Repeat dose toxicity testing + Bioanalysis / Toxicokinetics Drug Metabolism Reproductive Toxicity Testing (teratogenicity) Patients Small scale efficacy studies Patients Large scale multicentre studies Chronic (long term) toxicity testing + Bioanalysis / Toxicokinetics Reproductive Toxicity Testing (fertility and pre/post natal) Carcinogenicity studies Drug Metabolism Patients Large scale post-marketing studies As required Genetic toxicity (in vitro) Single / repeat dose toxicity studies + Bioanalysis / Toxicokinetics Safety Pharmacology Drug Metabolism Lead candidate Identified Clinical Non-clinical MOLECULE

4. RESEARCH & DISCOVERY

5. GLP PRINCIPLES

6. TEST FACILITY ORGANISATION AND PERSONNEL PRINCIPLE INVESTIGATOR QUALITY ASSURANCE UNIT ARCHIVIST(S)

7. TEST FACILITY MANAGEMENT’S RESPONSIBILITIES “ authority for the organization and functioning of the test facility” Ensures : sufficient number of qualified personnel, appropriate facilities, equipment, and materials are available for the timely and proper conduct of the study; maintenance of a record of the qualifications, training, experience and job description for each professional and technical individual; Standard Operating Procedures are established and followed, and approve all original and revised Standard Operating Procedures; Quality Assurance Programme with designated personnel Designate a Study Director for each study, Document approval of the study plan. Principal Investigator is designated, In multi-site study maintenance of an historical file of all Standard Operating Procedures; maintenance of a master schedule

8. STUDY DIRECTOR’S RESPONSIBILITIES approve the study plan and amendments ensure that the Quality Assurance personnel have a copy of the study plan study plans and amendments and Standard Operating Procedures to study personnel procedures are followed and documented acknowledge deviations sign and date the final report ensure that after completion (including termination) of the study, the study plan, the final report, raw data and supporting material are archived. “ single point of study control”

9. What is animal testing? Medical research on animals is the use of animals to test new drugs or toxic substances that could affect or kill a human. The term "animal testing" refers to procedures performed on living animals for purposes of research into basic biology and diseases, assessing the effectiveness of new medicinal products, and testing the human health and/or environmental safety of consumer and industry products such as cosmetics, household cleaners, food additives, pharmaceuticals and industrial/agro-chemicals.

10. maintain copies of all approved study plans and Standard Operating Procedures b) verify that the study plan c) conduct inspections Inspections can be of three types as specified by Quality Assurance Programme Standard Operating Procedures: - Study-based inspections, - Facility-based inspections, Process-based inspections. d) inspect the final reports prepare and sign a statement, to be included with the final report, QUALITY ASSURANCE PROGRAM

11. Medical experiments on prison inmates reportedly conducted in German concentration test effectiveness of SULFANILAMIDE- -Cuts deliberately made on the bodies of prisoners. Then the wounds were infected with bacteria. The infection aggravated by forcing wood shavings and ground grass into the wounds. Tested for effectiveness combating infection

12. Why Animal studies? Benefit –risk ratio can be calculated Prediction of therapeutic index Therapeutic index= Maximum tolerated dose Minimum curative dose Smaller ratio, better safety of the drug.

13. In other words… Pharmacological effects are same in man as in animals Toxic effect in species will predict adverse effects in man Giving high doses in animals improves predictability to man Risk assessment can be made by comparison of toxic doses in test species with predicted therapeutic dose in man

14. There are several steps involved with doing a Pre-Clinical Trial: File for approval as an Investigational New Drug (IND) 5 4 3 2 1 Establish Effective and Toxic Doses Screen the Drug in the Assay Develop a Bioassay Indentify a Drug Target

15. ` Toxicology  testing became important in the 20th century . In the 19th century, laws regulating drugs were more relaxed. For example, in the U.S., the government could only ban a drug after a company had been prosecuted for selling products that harmed customers . However, in response to the  Elixir Sulfanilamide disaster  of 1937 in which the eponymous drug killed more than 100 users, the U.S. congress passed laws that required safety testing of drugs on animals before they could be marketed. Other countries enacted similar legislation .  In the 1960s, in reaction to the  Thalidomide  tragedy, further laws were passed requiring safety testing on pregnant animals before a drug can be sold

16. ANIMAL MODEL An animal model is defined as a specific combination of an animal species, challenge agent and route of exposure that produces a disease process or pathological condition that in multiple important aspects corresponds to the human disease or condition of interest.     In the context of animal model qualification, the model-defining natural history studies are the animal studies that establish the ranges of values of key parameters of the disease or condition that will be specified in the context of use for the qualified model and that will be used as measures of quality control and quality assurance when the model is replicated.

17. Classification of animal models EXPERIMENTAL : A model in which an experimenting induced conditions mimic a human disease NEGATIVE : A model in which particular condition cant be produced , & is therefore studied to better understand the reason for the protective or resistant affects SPONTANEOUS : A model in which the animal naturally develops a disease or some other conditions of interest ALTERNATIVE MODEL is defined as technique that reduces or eliminates the need for live animals & there by prevents potential pain & distress in animals

18. ‘ Computer models and cell cultures are good for screening and are used frequently. Such models cannot replicate complicated interactions in the whole system. Final testing depends on studies in animals; sometimes it is required by law. Animal and non-animal models used in conjunction achieve the best answer .

19. Objectives of Preclinical Studies The purpose of pre-clinical study is to develop adequate data to decide that it is reasonably safe to proceed with human trials of the drug. Means, a laboratory test of a new drug or a new medical device, usually done on animal subjects, to see if the treatment really works and if it is safe to test on humans However the main objective is to collect the data to submit to the FDA for IND filing.

20. The types of studies included in preclinical trials 1.Screening Test 2. Tests on isolated organs, bacterial cultures 3. Tests on animal models of human disease 4. General observational test 5. Confirmatory tests and analogous activities 6. Mechanism of action 7. Systemic pharmacology 8. Quantitative test 9. Pharmacokinetics 10 . Toxicity test

21. Relevant Test Models Pharmacodynamic responses Pharmacokinetic profile Species, sex, age of experimental animals Susceptibility, sensitivity and reproducibility of test system In vitro: Isolated organs, tissues cell-cultures Mechanism of effect in vivo

22. Types of toxicology studies Systemic toxicology studies Single dose studies Repeated dose studies Reproductive toxicology studies Male fertility Female reproduction & Developmental studies Local toxicity studies Hypersensitivity studies Genotoxicity studies Carcinogenicity studies

23. Systemic toxicology studies Preliminary Definitive Maximum Non Lethal dose (MNLD) determined MTD and MLD determined Evaluate effects Target organ of toxicity may be determined SINGLE DOSE STUDIES/ ACUTE TOXICITY

24. Preliminary studies METHOD Single dose tested in 2 rodent species 2 routes of administration Oral dosing of 2g/kg or 10 times of normal human dose Observation for 14 days after dosing MNLD established Symptoms , signs reported Microscopic and Macroscopic evaluation

25. Definitive studies METHOD Group of 20 animals of either sex dosed at MNLD 5 animals of each sex are observed for 48 hr and conduct autopsy for early pathological changes Remaining 5 of each sex are observed for 14 days MTD and MLD established Signs of intoxication or recovery, changes in body weight, pathological changes Complete macroscopic and microscopic examination Target organs can be identified

26. Two mammalian species(one should be non-rodent) Long duration studies (30-180 days) Dose is dependent on dose-escalating studies Drug administered by clinical route Parameters monitored and recorded are: Behavioral Physiological Biochemical Macroscopic & Microscopic observations b) REPEATED DOSE STUDIES/SUB-ACUTE OR CHRONIC TOXICITY

27. B. Reproductive toxicology studies a) MALE FERTILITY METHOD One rodent species(rat) 3 dose groups+ 1 control (each with 6 adult males), Drug treatment by clinical route for 28-72 days Mated with females in 1:2 ratio Females getting pregnant should be examined After 13 days of gestation All male animals sacrificed Weights of testis, epididymus recorded & examined for their histology Sperms examined for motility & morphology

28. Segment I 31 Fertility and general reproductive performance study Segment II Teratogenicity Segment III Peri and post-natal study Fertility and early embryonic development (rat) Embryo- foetal development (rat & rabbit) Post natal development (rat) (post natal survival of offspring), growth parameters, vital senses, behavioral effects b) FEMALE FETILITY Drug administered to both males (28days) and females (14 days) before mating Implantation Embryogenesis

29. Dermal toxicity studies Dermal photo-toxicity studies Vaginal toxicity studies Rectal tolerance studies Rats & Rabbit Local signs ( erythema , oedema ), histological examination Guinea pig Used in treatment of leucoderma Examination of erythema & oedema formation Rabbit or Dog Observation of swelling, histopathology of vaginal wall Rabbit or Dog Signs of pain, blood or mucous, histology examination of rectal mucosa Types of local toxicity studies C. Local toxicity studies Required when drug is administered by special route (other than oral) in humans

30. Ocular toxicity studies Parenteral drugs Inhalation toxicity studies Albino Rabbit Changes in cornea ,Iris & aqueous humor, histological examination of eye For intravenous/ intramuscular/ subcutaneous/ intra-dermal injection Sites of injection examined grossly and microscopically One rodent and non rodent species Acute , sub-acute and chronic studies performed Observation of respiratory rate Histological examination of respiratory passages, lung tissue

31. D. allergenicity /hypersensitivity toxicology studies Guinea Pig Maximization test Local lymph node assay Determination of Maximum non irritant or minimum irritant dose Evaluation of Erythema and oedema Mice of one sex(either male or female) Drug treatment given on ear skin Auricular lymph node dissection after 5 days Increase in 3h-thymidine used for evaluation

32. E. Genotoxicity studies To detect early tumorigenic effects in cases of chronic illness In vitro tests: Test for gene mutation in Bacteria Cytogenetic evaluation of chromosomal damage in mammalian cells E.g .; Ames’s Salmonella Assay detects increased number of aberrations in metaphase chromosomes DNA strand breaks, DNA repair or recombination, Measurements of DNA adducts In vivo tests: Chromosome damage in rodent hematopoietic cells E.g .; Micronucleus Assay

33. f. Carcinogenicity/ oncogenicity studies Life-time Bioassays Carcinogenicity studies are performed on: Drug used for >6 months or frequent intermittent use for chronic diseases Chemical structure of drug indicates carcinogenic potential Therapeutic class of drugs which have produced positive carcinogenicity Usually carried out for 24 months in rats and 18 months in mice (life span studies)

34. ANIMAL EXPERIMENTS: REGULATORY MECHANISMS IN INDIA Institute Animal Ethics Committee (IAEC) Committee for the Purpose of Control and Supervision of Experiments in Animals (CPCSEA) Drugs & Cosmetics Act, 1940, Appendix-I Department of Animal Husbandry, Dairying & Fisheries, Ministry of Agriculture, New Delhi-2001 Department of Biotechnology. The Prevention of Cruelty to Animals Act, 1960 as amended up to 30th July 1982 and Animal Welfare Board

35. CRITERIA`S FOR SELECTION OF LIVE ANIMAL EXPERIMENT Procedure should yield results beneficial to well being The species & no. of animals should be appropriate for experimental purpose The proposed procedures shouldn’t unnecessarily duplicate previous experiment Appropriate analgesics , anesthetics & tranquilizing drugs to be used to minimize pain & discomfort

36. Guide for the care & use of laboratory animals INSTITUTIONAL POLICIES Monitoring the care & use of animals Personal qualifications Personal hygiene Occupational health Experiments involving hazardous agents Special consideration

37. 2) LABORATORY ANIMAL HUSBANDRY Housing Animal environment Food , water & bedding Sanitation Identification & record keeping Emergency , weekend & holiday care

38. 3) Veterinary care Preventative medicine Surveillance , diagnosis , treatment & control of diseases Anesthesia & analgesia Surgery & post surgical care Euthanasia

39. . Methods of euthanasia The individuals performing the experimental procedure & caring for the animals need to be properly trained In general procedures that causes minimal pain or discomfort to humans & place the animals in minimum distress are considered ACCEPTABLE

40. EUTHANASIA Methods of euthanizing laboratory animals are chosen to induce rapid unconsciousness and humane death without pain or distress .  The methods that are preferred are those published by councils of veterinarians. The animal can be made to inhale a gas, such as  carbon monoxide  and  carbon dioxide , by being placed in a chamber, or by use of a face mask, with or without prior sedation or anesthesia

41. . PHYSICAL EUTHANASIA : cervical dislocation & decapitation recommended only when scientifically justified Cervical dislocation is considered humane for poultry , mice , rats weighing less than 200 g & rabbit weighing less than 1 kg VERIFICATION OF DEATH : irregardless of specific euthanasia methods used , it is imperative that death be verified by examining the animal for cessation of vital signs