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USMLE/1
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1. Anatomy
2. Microbiology
3. Physiology
4. Pathology
5. Pharmacology
6. Immunology
7. Biochemistry
8. Cell and molecular biology
9. Biostatistics and epidemiology
9.1 Measure of disease frequency
9.2 Measures of health status
9.3 Reportable diseases
9.4 Variables and distributions
9.5 Standard deviation and confidence intervals
9.6 Measures of association
9.7 Types of study design
9.8 Bias
9.9 Hypothesis testing
9.10 Sensitivity, specificity and predictive values
9.11 Phases of drug approval
9.12 Doctor patient relationships, ethics and decision-making capacity
9.13 Additional information
10. Genetics
11. Behavioral science
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9.11 Phases of drug approval
Achievable USMLE/1
9. Biostatistics and epidemiology

Phases of drug approval

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Phase Description
I (drug discovery and development) Studies are conducted to find efficacy, appropriate dosage, methods for administration, side effects, metabolism, excretion and drug interactions
II (preclinical studies) Drug is tested in vivo and/or vitro, to determine its potential for harm (toxicity)
III (clinical research) Phase 1: Involves 20-100 study participants and lasts several months. Used to determine the safety and dosage of the drug, and about 70% of these drugs move on to the next clinical research phase.
Phase 2: Involves up to several hundred people with condition of interest. Lasts few months to two years. Used to monitor the efficacy of the drug, as well as note side effects. Only 30% drugs move to the next phase.
Phase 3: Involves 300-3000 volunteers and can last up to four years. It is used to continue monitoring the efficacy of the drug, as well as exploring any longer-term adverse reactions. About 25% to 30% of drugs move to the next phase.
Phase 4: Involves several thousands of volunteers who have the disease or condition and continues to monitor safety and efficacy. If a drug passes this phase, it goes on to FDA review.
IV (FDA review) Takes 6-10 months.
V (post-market monitoring) Available for sale, safety monitoring continues.
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