1.2 Drug Development, Trials And Advertising Flashcards
Stages in drug development
- Drug Discovery
- Clinical Trials
- Health Canada/FDA Approved Drug
Drug Discovery
-3-6 years total Sub stage - research and discovery of target # of cmpds - up to 25,000 Result -discovery of lead compounds
Sub stage -preclinical testing # of cmpds - up to 30 Result - determine safety and potential efficacy
Clinical trials (6-7 years total)
Phase 1 - 5-30 - safety and tolerability Phase 2 - 2-3 - effectiveness, safety, and pharmacokinetics Phase 3 - 1 - effectiveness and safety
Health Canada/FDA Approved the drug (0.5-2 years total)
Health Canada review and manufacturing - 1 - drug approval and production Phase 4 - 1 - long term safety
Preclinical studies
Prior to testing new drug in humans tested on molecular and cellular studies, tissue and whole animal studies
Toxicology studies
These studies determine the effect of the new drug on organ systems other than the targeted organ. All drugs have some toxicity at some dose in some individuals
Pharmacology studies
studies determine the detailed mechanism of action of the new drug for example if the drug has been developed to treat high blood pressure it would be determined how the drug lowers blood pressure
Initial steps to test a new drug in humans
- The manufacturers required to submit proof of the safety and efficacy of the drug in several animal species to the government regulatory agency in the particular country concerned
- The detailed methodology of the proposed clinical trial in humans is required
- The submission is carefully evaluated by qualified scientists in the regulatory agency if they are satisfied permission will be given
Phase 1 clinical trials
- Trials are conducted in a limited number 20-100 of healthy volunteers
- The absorption distribution elimination and adverse effects of the new drug are carefully studied
- One or two doses of the new drug administered and tolerability of the drug is determined
Phase 2 clinical trials
- conducted in patients who have the disease or condition for which the drug is designed to treat
- determine whether the drug is effective in treating the condition it is recommended for
- careful attention is paid to the safety of the drug
Phase 3 clinical trials
- Main studies used for the licensing of marketing of the drug
- Test the drug in a larger number of people usually 1000 or more to obtain more info on the safety and efficacy of the drug
- last months to years and are conducted at centres in many cities as one does not have the required number of or diversity of patients
- $1 million-$50 million
- main goal to test whether the drug is save and effective
Elements of a clinical trial
Phase 3 clinical trials designed with the same components to ensure that the results are as reliable as possible
Target population
Target population must be a group of patients for whom the drug is intended for patients involved in the study would have to have prior diagnosis of the disease of study
Inclusion and exclusion criteria
- Patients with multiple diseases that could influence the results are excluded
- there should also be a severity of different levels of the disease
Ethical considerations and consent
- Before a person is able to participate consent must be obtained
- consent document should outline the purpose of the study the procedures the effects the risks and the benefits
- patients must fully understand the consent contract before the trial begins
Study population randomized allocation
A computer generator will divide patients into a control group and experimental group removing bias
Treatment
The patience and the treatment group will receive the experimental drug
Control
Experimental drug has to be compared to a controlled drug which will either be a possible gold standard drug depending on the disease
Placebo
A tablet that does not contain any active drug but as identical in appearance colour taste in size of the tablet containing the active drug.
Gold standard drug
Is the new drug that is excepted by the medical community has the best available treatment for the specific disease at that time
Blinded assessment
The staff administration or the patient receiving cannot be aware of who is receiving Which drug to remove bias
Outcome
- Result of treatments should be measured in objective and reliable manner
- measuring at the same time each day/taking at the same time each day
Compliance
Compliance says if the results of the trial or valid patient usually asked to return their unused drug at the clinic each visit to see the accuracy of the overall compliance
Quality of life
- Clinical trials will measure the impact of the drug or treatment on the quality of life
- some drugs may be effective in treating the disease but may not improve the quality of life
Analysis of the results
The experimental drug must be compared to the control drug using statistics if successful will be granted approval
Bioavailability studies
- new brand name drugs and the generic drug will contain the identical active ingredients as the original brand name drug, in the same amount and usually in the same dosage form
Bioavailability
The proportion of an administered dose of a drug that reaches the systemic circulation in an unchanged form
Bioequivalent
The two drug products generic and brand-name which contain the same active ingredients and give similar blah blah those are said to be bioequivalent
Phase 4 clinical trials
Risks that are delayed or less frequent than 1 in 1000 administrations may be missed in the phase 3 trial. Thus, surveillance of the effects of the drugs are required after the drug is released for general use
- referred to as the post marketing surveillance
