Glossary

Post Marketing Commitment Glossary¹

Adverse event – Any untoward medical occurrence in a patient, clinical investigation subject, or consumer following administration of a medicine. The event need not necessarily have a causal relationship with the treatment or usage.

Arm – Any of the treatment groups in a randomized trial. Most randomized trials have two "arms"; some have three or more. Open-label studies have one arm.

Baseline – Information gathered at the beginning of a study from which variations found in the study are measured; a known value or quantity with which an unknown is compared when measured or assessed; and/or the initial time point in a clinical trial, just before subjects begin receiving the experimental treatment being tested.

Blind – A randomized trial is "blind" if subjects and study personnel (investigators, nurses, companies) are not told which arm of the trial the patient is in. A clinical trial is "blind" if subjects and study personnel are unaware of whether they are in the experimental or control (placebo) arm of a study. Blinded studies are used to prevent bias.

Clinical trial/Clinical study – A research study to answer specific questions about vaccines, new treatments, or new ways of using known treatments. Clinical trials (also called medical research and research studies) are used to determine the benefit/risk profile of new medicines or treatments. Carefully conducted clinical trials are the fastest and safest way to find treatments that work in people.

Control group – The standard by which experimental observations are evaluated. In many clinical trials, one group of subjects will be given an experimental drug or treatment, while the control group is given either a standard treatment for the illness or a placebo.

Dose ranging study – A clinical trial in which two or more doses of an agent (such as a medicine) are tested against each other to determine which dose works best and is least harmful.

Double-blind study – A clinical trial design in which neither the participating subjects nor the study staff knows which subjects are receiving the experimental medicine and which are receiving a placebo or another therapy.

Drug-drug interaction – A modification of the effect of a medicine when administered with another medicine. The effect may be an increase or decrease in the action of either substance, or it may be an adverse event not normally associated with either medicine.

Efficacy (of a medicine or treatment) – The ability of a medicine or treatment to produce a result. A medicine passes efficacy trials if it is effective at the dose tested and against the illness for which it is prescribed. In the procedure mandated by the FDA, Phase 2 clinical trials gauge efficacy, and Phase 3 trials confirm it.

Endpoint – Overall outcome that the protocol is designed to evaluate. Common endpoints are efficacy endpoints, treatment outcomes, severe toxicity, disease progression, or death.

Epidemiology – The branch of medical science that deals with the study of incidence and distribution and control of a disease in a population or sub-population. Epidemiological studies can also be designed to evaluate medicine safety.

Inclusion/exclusion criteria – The medical or social standards determining whether a subject may be chosen to enter a clinical trial or epidemiologic study. These criteria are based on such factors as age, gender, type and stage of disease, previous treatment history, and other medical conditions.

Indication – A valid reason to use a certain test, medication, procedure, or surgery. The FDA strictly regulates indications for medications available in the U.S. including the specific information under the “Indications and Usage” section of each medicine’s full U.S. Physician Prescribing Information.

Informed consent – A process by which a subject voluntarily confirms his or her willingness to participate in a particular trial, after having been informed of all aspects of the trial that are relevant to the subject’s decision to participate.

Institutional Review Board (IRB) – An independent committee of physicians, statisticians, researchers, community advocates, and others that ensures that a study is ethical and that the rights of study participants are protected. All clinical trials in the U.S. must be approved by an IRB before they begin. Every institution that conducts or supports biomedical or behavioral research involving human participants must, by federal regulation, have an IRB that initially approves and periodically reviews the research in order to protect the rights of human participants.

New Drug Application (NDA) – An application for a license to market a medicine for a specified indication, submitted to the U.S. FDA after clinical trials have been completed.

Open-label study – A study in which doctors and participants know which medicine or vaccine is being administered.

Outcomes studies – Studies of the end results of particular health care practices and interventions, including effects that subjects experience and care about, such as change in the ability to function.² For subjects with chronic conditions, where a cure is not always possible, end results may include quality of life measures, mortality (death), or morbidity (complications).

Pharmacokinetics – The processes in a living organism of absorption, distribution, metabolism, and excretion of a medicine or vaccine.

Phase of study – Studies are conducted in phases of development. Click for definitions of Phase 1, Phase 2 and Phase 3. Phase 4 refers to studies conducted after license approval, and may include post marketing commitments.

Placebo-controlled study – A method of medicine investigation in which an inactive substance (the "placebo") is given to one group of subjects, while the test medicine is given to another group. Results obtained in the two groups are then compared to see if the investigational treatment is more effective in treating the condition.

Pregnancy registries – Surveillance studies that enroll pregnant women after they have been taking medicine and before the birth of the baby. Babies born to women taking a particular medicine are compared with babies of women not taking the medicine. Usually, evaluation of a large number of pregnancies is needed to determine the potential effect of the medicine on the babies.³

Quality of life trial – Exploration of ways to measure comfort and quality of life for individuals with chronic illnesses.

Randomization – A method based on chance by which study subjects are assigned to a treatment group. The method minimizes differences among groups by equally distributing people with particular characteristics among all trial arms.

Sample size – The number of patients or experimental units required for a trial.

Side effects – Any undesired action or effect of a medicine or treatment. Negative or adverse effects may include headache, nausea, hair loss, skin irritation, or other physical problems. Experimental medicine must be evaluated for both immediate and long-term effects.

Single-blind study – A study in which one party, either the investigator or subject, does not know the medication being taken by the subject.

Statistical significance – The probability that an event or difference occurred by chance alone. In clinical trials, the level of statistical significance depends on the number of subjects studied and observations made, as well as the magnitude of differences observed.

Study endpoint – A primary or secondary outcome used to judge the effectiveness or safety of a treatment.

Surveillance study – A study designed to obtain additional safety and/or efficacy data. These studies may be clinical trials or non-interventional, and are often conducted as a post marketing (Phase 4) activity.

Toxicity – An adverse event produced by a medicine that is detrimental to the subject’s health. The level of toxicity associated with a medicine varies with the condition for which the medicine is used.

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¹ Clinicaltrials.gov Glossary, http://clinicaltrials.gov/ct/info/glossary.

² Agency for Healthcare Research and Quality, http://www.ahrq.gov/clinic/outfact.htm.

³ U.S. FDA Guide to Pregnancy Registries, http://www.fda.gov/womens/registries/general.html.

About the Information Posted on This Web Site:

This Web site contains information about Pfizer’s U.S. pharmaceutical post marketing commitments. The post marketing commitments listed here include pre-clinical, clinical and epidemiological studies or testing agreed to by Pfizer (including its subsidiaries) and the FDA, and are used to gather additional information about the safety, efficacy, or use of approved Pfizer medicines. This Web site provides the current status of Pfizer post marketing commitments listed on the FDA Web site and includes post marketing commitments established for Pfizer medicines in the U.S. since August 1, 2000. New post marketing commitments will be listed on this Web site as they are established. Released or completed post marketing commitments will be removed from the site.

This Web site does not contain technical chemistry, manufacturing and control (CMC) commitments, or commitments for medicines where Pfizer is not the FDA license holder. Information about Pfizer’s post marketing commitments to the U.S. FDA is believed to be correct at the time that the information is posted, and is subject to change as progress is made in fulfilling the commitments.

This Web site is updated monthly. The status of post marketing commitments shown on the FDA Web site may differ from information displayed on this site, due to differences in the timing of updates made to the FDA Web site. The number of commitments on the two sites may also differ, due to the frequency of such updates and/or due to multiple reporting of single commitments on the FDA Web site.