Chapter 3 - (Drug Regulation, Development, Names and Info) Flashcards
The fast track system of drug approval
AKA accelerated approval, a drug could be approved for marketing prior to completion of phase III trials. The rationale for this change was 1) medications are needed, even if their benefits may be marginal and 2) the unknown risks associated with early approval are balanced by the need for more effective drugs. The fast track system created for AIDS drugs and cancer drugs now includes drugs for other serious and life-threatening illnesses.
Randomized Controlled Trial
and 3 distinguishing features
Randomized controlled trials (RCTs) are the most reliable way to objectively assess drug therapies.
RCTs have three distinguishing features:
- use of controls
- randomization
- blinding.
Control (in a trial)
used as a standard of comparison for checking the results of an experiment.
[When studying a new drug, subjects receiving either the standard drug or the placebo are referred to as controls–They help us determine if the new treatment is more (or less) effective than standard treatments, or at least if the new treatment is better (or worse) than no treatment at all. Likewise, controls allow us to compare the safety of the new drug with that of the old drug, a placebo, or both.]
Randomization
Subjects are randomly assigned to either the control group or the experimental group (ie, the group receiving the new drug).
[The purpose of randomization is to prevent allocation bias, which results when subjects in the experimental group are different from those in the control group.]
Single Blind
A blinded study is one in which the people involved do not know to which group—control or experimental—individual subjects have been randomized.
[If only the subjects have been “blinded,” the trial is referred to as single blind.]
Double Blind
A blinded study is one in which the people involved do not know to which group—control or experimental—individual subjects have been randomized.
[If the researchers as well as the subjects are kept in the dark, the trial is referred to as double blind. Double-blind trials are more objective than single blind.]
Phase I trial
what are the 3 goals
Phase I trials are usually conducted in HEALTHY VOLUNTEERS. Phase I testing has three goals:
1) evaluating drug metabolism,
2) pharmacokinetics, and
3) biologic effects.
Phase II
Drugs are tested in patients. The objectives: determine therapeutic effects and dosage range. 500-5000 patients receive the drug, only a few hundred take it for more than 3-6mo
Phase III trial
Drugs tested in patients. Differs from Phase II in that upon completing phase 3, the drug moves to the FDA for conditional approval for a New Drug Application
Phase IV: Postmarketing Surveillance
If FDA accepts drug, trial moves to Phase 4. Drug is released for general use, permitting observation of its effects in a large population.
Adverse Effect (failure to detect all and why)
Premarketing clinical trials cannot detect all adverse effects before a new drug is released. There are three reasons why:
(1) during clinical trials, a relatively small number of patients are given the drug;
(2) because these patients are carefully selected, they do not represent the full spectrum of individuals who will eventually take the drug; and
(3) patients in trials take the drug for a relatively short time.
Because of these unavoidable limitations in the testing process, effects that occur infrequently, effects that take a long time to develop, and effects that occur only in certain types of patients can go undetected. Hence, despite our best efforts, when a new drug is released, it may well have adverse effects of which we are as yet unaware.
Chemical Name
description of a drug using the nomenclature of chemistry. A drug’s chemical name can be long and complex. Because of their complexity, chemical names are inappropriate for everyday use.
For example, few people would communicate using the chemical term N-acetyl-para-aminophenol when a more simple generic name (acetaminophen) or trade name (eg, Tylenol) could be used.
Generic Name
The generic name of a drug is assigned by the United States Adopted Names Council.
- Each drug has only one generic name.
- The generic name is also known as the nonproprietary name. Generic names are less complex than chemical names.
Trade Name
Trade names, also known as proprietary or brand names, are the names under which a drug is marketed.
Trade names must be approved by the FDA.
OTC (Over-the-Counter)
OTC products that have similar or identical trade names can actually contain different drugs.
[For example, although the two Lotrimin AF products have identical trade names, they actually contain two different drugs: miconazole and clotrimazole. Confusion would be avoided by labeling these products miconazole spray and clotrimazole cream, rather than labeling both Lotrimin AF.]
