Adherence
Taking medications or following a treatment programme as prescribed. Adherence includes following instructions concerning food (i.e., taking medication with a meal, or not eating certain foods) and dosing schedules. A low level of adherence can lead to the development of drug resistance.
Adverse event
In a clinical trial, an unwanted effect detected in participants. The term is applied whether or not the effect can be attributed to the treatments under study.
Analytical treatment interruption (ATI)
A short-term, well-controlled treatment (ART) interruption used in combination with another treatment approach, i.e., an immunotherapy or an ART sparing interval, to test a new therapeutic concept or drug
Antiretroviral
A substance that stops or suppresses the activity of a retrovirus such as HIV (e.g., AZT or 3TC).
Arm
A group of participants in a clinical trial, all of whom receive the same treatment(s).
Asymptomatic
Without symptoms. In HIV/AIDS literature, a person who tests positive for HIV antibodies, but who shows no clinical symptoms of the disease.
Attachment inhibitor
See entry inhibitor.
Baseline
1) Information gathered at the beginning of a study from which variations found in the study are measured. 2) A known value or quantity against which an unknown is compared when measured or assessed.
Blinded study
A clinical trial in which participants do not know if they are in the experimental group (receiving the experimental treatment) or the control group (receiving the standard treatment) of the study. See also double-blind study and single-blind study.
Buyer’s club
Cooperative organizations that provide easier access to treatments for people living with HIV.
CD4+ cells
Usually referred to simply as CD4 cells, these are the preferred target of HIV. CD4 cells are white blood cells that normally orchestrate the immune response by signaling other cells in the immune system to perform their special functions. The destruction of CD4 cells is the major cause of the immunodeficiency observed in AIDS. Also called a T-helper cell.
CD4+ cell count
A measure of the number of immune system cells that have CD4 receptors.
Clinical trial
A carefully designed experiment that allows scientists to test their research questions in people.
Clinical trial application (CTA)
A Clinical Trial Application must be filed with Health Canada before an experimental drug can be studied in a Phase I, II or III clinical trial (Phase IV trials do not need to be filed).
Co-infection
A term used to describe infection with both HIV and another virus, such as hepatitis B or C.
Community advisory committee
An independent committee that reviews and makes recommendations regarding the informed consent section of a clinical trial protocol. CACs exist primarily to inject a community perspective into the clinical trials process, and to improve communication between researchers and community representatives.
Comparison trial
A study in which an experimental treatment is tested against the standard treatment or a placebo, or in which different doses of the same treatment are tested. See also dose comparison trial.
Compassionate access/use
A trial that allows people who do not participate in the research study (because they do not meet the inclusion criteria or for other reasons) to have access to the drug or treatment being tested. Most compassionate arms are restricted (for example, to those with CD4 cell count below specified amount, intolerant to standard therapy, etc.).
Concomitant medications
Drugs that are taken together. Certain concomitant medications can have adverse (harmful) reactions, while others can have beneficial effects (e.g. ritonavir is commonly used to boost other protease inhibitors).
Controls
Specific measures that researchers and participants must follow to reduce any bias that could affect the results of a trial.
Control group
The group of participants in a clinical trial who receive the standard treatment or a placebo. See also controlled trial.
Controlled trial
Trials in which one group gets an experimental treatment and another gets either a placebo or an approved therapy. Participants do not usually know which group they are in.
Crossover trial
A clinical trial in which all participants receive both treatments, but at different times. Halfway through the study, one group is switched from the experimental treatment to the control treatment (standard treatment), and the other group is switched from the control to the experimental treatment.
Dose
The measured amount of a particular treatment to be taken at one time.
Dose comparison trial
A trial that compares different amounts of the same drug. Sometimes different doses are tested against a placebo.
Double-blind trial
Participants in this type of trial are divided into two or more groups: one gets the experimental treatment; the other gets the standard treatment or a placebo. Neither the researchers nor the participants know who is taking which drug until the trial is over.
Drug-class sparing regimen
A treatment strategy in which one class of antiretroviral drug is excluded from the treatment regimen in order to reduce drug toxicity and address or avoid side effects.
Dyslipidemia
A condition involving an increase in the level of lipids (e.g., cholesterol and triglycerides) in the body. Dyslipidemia is a common side effect of highly active antiretroviral therapy (HAART).
Efficacy
How well a treatment works (i.e., how effective it is).
Endpoint
An event used by clinical trial researchers to evaluate whether an experimental treatment is working. For example, developing AIDS or a low CD4 count may be the endpoint of a trial for people who had no previous symptoms.
Entry inhibitor
A class of antiretroviral drugs that interfere with HIV’s ability to enter immune cells which include CCR5 antagonists and fusion inhibitors.
Expanded access programme
A trial that allows people who do not participate in the research study (because they do not meet the inclusion criteria or for other reasons) to have access to the drug or treatment being tested. Many programmes are restricted (e.g. participants must have a CD4 count below a specified amount or be intolerant to the standard treatments).
Experimental agent
A substance (drug or other treatment) not yet approved for marketing by Health Canada, which is being studied in a clinical trial.
Food and drug administration (FDA)
The main U.S. Public Health Service agency responsible for ensuring the safety and efficacy of drugs and medical devices used in the diagnosis, treatment and prevention of HIV infection, AIDS and AIDS-related opportunistic infections.
Fusion inhibitor
A type of entry inhibitor that stops HIV from fusing to a cell. See also entry inhibitor.
Adherence
Taking medications or following a treatment programme as prescribed. Adherence includes following instructions concerning food (i.e., taking medication with a meal, or not eating certain foods) and dosing schedules. A low level of adherence can lead to the development of drug resistance.
Adverse event
In a clinical trial, an unwanted effect detected in participants. The term is applied whether or not the effect can be attributed to the treatments under study.
Antiretroviral
A substance that stops or suppresses the activity of a retrovirus such as HIV (e.g., AZT or 3TC).
ARM
A group of participants in a clinical trial, all of whom receive the same treatment(s).
Asymptomatic
Without symptoms. In HIV/AIDS literature, a person who tests positive for HIV antibodies, but who shows no clinical symptoms of the disease.
Attachment inhibitor
See entry inhibitor.
Baseline
1) Information gathered at the beginning of a study from which variations found in the study are measured. 2) A known value or quantity against which an unknown is compared when measured or assessed.
Blinded study
A clinical trial in which participants do not know if they are in the experimental group (receiving the experimental treatment) or the control group (receiving the standard treatment) of the study. See also double-blind study and single-blind study.
Buyer’s club
Cooperative organizations that provide easier access to treatments for people living with HIV.
CD4+ cells
Usually referred to simply as CD4 cells, these are the preferred target of HIV. CD4 cells are white blood cells that normally orchestrate the immune response by signaling other cells in the immune system to perform their special functions. The destruction of CD4 cells is the major cause of the immunodeficiency observed in AIDS. Also called a T-helper cell.
CD4+ cell count
A measure of the number of immune system cells that have CD4 receptors.
Clinical trial
A carefully designed experiment that allows scientists to test their research questions in people.
Clinical trial application (CTA)
A Clinical Trial Application must be filed with Health Canada before an experimental drug can be studied in a Phase I, II or III clinical trial (Phase IV trials do not need to be filed).
Co-infection
A term used to describe infection with both HIV and another virus, such as hepatitis B or C.
Community advisory committee
An independent committee that reviews and makes recommendations regarding the informed consent section of a clinical trial protocol. CACs exist primarily to inject a community perspective into the clinical trials process, and to improve communication between researchers and community representatives.
Comparison trial
A study in which an experimental treatment is tested against the standard treatment or a placebo, or in which different doses of the same treatment are tested. See also dose comparison trial.
Compassionate access/use
A trial that allows people who do not participate in the research study (because they do not meet the inclusion criteria or for other reasons) to have access to the drug or treatment being tested. Most compassionate arms are restricted (for example, to those with CD4 cell count below specified amount, intolerant to standard therapy, etc.).
Concomitant medications
Drugs that are taken together. Certain concomitant medications can have adverse (harmful) reactions, while others can have beneficial effects (e.g. ritonavir is commonly used to boost other protease inhibitors).
Controls
Specific measures that researchers and participants must follow to reduce any bias that could affect the results of a trial.
Control group
The group of participants in a clinical trial who receive the standard treatment or a placebo. See also controlled trial.
Controlled trial
Trials in which one group gets an experimental treatment and another gets either a placebo or an approved therapy. Participants do not usually know which group they are in.
Crossover trial
A clinical trial in which all participants receive both treatments, but at different times. Halfway through the study, one group is switched from the experimental treatment to the control treatment (standard treatment), and the other group is switched from the control to the experimental treatment.
Dose
The measured amount of a particular treatment to be taken at one time.
Dose comparison trial
A trial that compares different amounts of the same drug. Sometimes different doses are tested against a placebo.
Double-blind trial
Participants in this type of trial are divided into two or more groups: one gets the experimental treatment; the other gets the standard treatment or a placebo. Neither the researchers nor the participants know who is taking which drug until the trial is over.
Drug-class sparing regimen
A treatment strategy in which one class of antiretroviral drug is excluded from the treatment regimen in order to reduce drug toxicity and address or avoid side effects.
Dyslipidemia
A condition involving an increase in the level of lipids (e.g., cholesterol and triglycerides) in the body. Dyslipidemia is a common side effect of highly active antiretroviral therapy (HAART).
Efficacy
How well a treatment works (i.e., how effective it is).
Endpoint
An event used by clinical trial researchers to evaluate whether an experimental treatment is working. For example, developing AIDS or a low CD4 count may be the endpoint of a trial for people who had no previous symptoms.
Entry inhibitor
A class of antiretroviral drugs that interfere with HIV’s ability to enter immune cells which include CCR5 antagonists and fusion inhibitors.
Expanded access programme
A trial that allows people who do not participate in the research study (because they do not meet the inclusion criteria or for other reasons) to have access to the drug or treatment being tested. Many programmes are restricted (e.g. participants must have a CD4 count below a specified amount or be intolerant to the standard treatments).
Experimental agent
A substance (drug or other treatment) not yet approved for marketing by Health Canada, which is being studied in a clinical trial.
Food and drug administration (FDA)
The main U.S. Public Health Service agency responsible for ensuring the safety and efficacy of drugs and medical devices used in the diagnosis, treatment and prevention of HIV infection, AIDS and AIDS-related opportunistic infections.
Fusion inhibitor
A type of entry inhibitor that stops HIV from fusing to a cell. See also entry inhibitor.
Gene therapy
An approach to preventing and/or treating diseases by replacing, removing, or altering key genes, or otherwise manipulating genetic material.
Good clinical practice (GCP)
An international ethical and scientific quality standard for designing, conducting, recording and reporting clinical trials.
Hepatitis
Hepatitis is inflammation of the liver. It can be a viral infection or drug induced. Two forms of viral hepatitis, hepatitis B and hepatitis C, are fairly common in people with HIV infection. See also co-infection.
Highly active antiretroviral therapy (HAART)
Combination antiretroviral therapy that typically includes three drugs from at least two different classes.
HIV-2
A retrovirus that causes AIDS and that is less virulent and has a longer incubation period than HIV-1, the most prevalent HIV.
Immunomodulators
Drugs that strengthen the immune system and help the body to fight off infections or other diseases that attack people living with HIV/AIDS.
Inclusion/exclusion criteria
Conditions that determine why a person may or may not be allowed to enter a trial. For example, most trials do not allow pregnant women to join. Others do not allow people to take certain drugs, and others exclude people with certain illnesses.
Informed consent
A process in which the risks, benefits, and requirements of a trial are explained to volunteers. Before entering the trial, participants must sign an informed consent form, which should include a plain-language description of the benefits, risks, and basic structure of the trial.
Institutional review board(IRB)
See Research Ethics Board.
Insulin resistance
A condition in which the body is unable to use available insulin effectively. Insulin resistance is a common side effect of highly active antiretroviral therapy (HAART).
Intervention
A treatment or treatment strategy tested in a clinical trial.
Lactic acidosis
A condition involving dangerously high levels of lactic acid in the blood. While lactic acidosis is rare, increased levels of lactic acid are a fairly common side effect of highly active antiretroviral therapy (HAART).
Lipodystrophy
A condition involving the defective metabolism of fat by the body. Lipodystrophy includes fat loss (e.g. wasting in the arms, legs and face) and fat displacement (e.g. “buffalo hump,” the accumulation of fat in the upper back). Lipodystrophy is a common side effect of highly active antiretroviral therapy (HAART).
Good clinicl practice (GCP)
An international ethical and scientific quality standard for designing, conducting, recording and reporting clinical trials.
Hepatitis
Hepatitis is inflammation of the liver. It can be a viral infection or drug induced. Two forms of viral hepatitis, hepatitis B and hepatitis C, are fairly common in people with HIV infection. See also co-infection.
Highly active antiretroviral therapy (HAART)
Combination antiretroviral therapy that typically includes three drugs from at least two different classes.
HIV-2
A retrovirus that causes AIDS and that is less virulent and has a longer incubation period than HIV-1, the most prevalent HIV.
Immunomodulators
Drugs that strengthen the immune system and help the body to fight off infections or other diseases that attack people living with HIV/AIDS.
Inclusion/exclusion criteria
Conditions that determine why a person may or may not be allowed to enter a trial. For example, most trials do not allow pregnant women to join. Others do not allow people to take certain drugs, and others exclude people with certain illnesses.
Informed consent
A process in which the risks, benefits, and requirements of a trial are explained to volunteers. Before entering the trial, participants must sign an informed consent form, which should include a plain-language description of the benefits, risks, and basic structure of the trial.
Institutional review board(IRB)
See Research Ethics Board.
Insulin resistance
A condition in which the body is unable to use available insulin effectively. Insulin resistance is a common side effect of highly active antiretroviral therapy (HAART).
Intervention
A treatment or treatment strategy tested in a clinical trial.
Lactic acidosis
A condition involving dangerously high levels of lactic acid in the blood. While lactic acidosis is rare, increased levels of lactic acid are a fairly common side effect of highly active antiretroviral therapy (HAART).
Lipodystrophy
A condition involving the defective metabolism of fat by the body. Lipodystrophy includes fat loss (e.g. wasting in the arms, legs and face) and fat displacement (e.g. “buffalo hump,” the accumulation of fat in the upper back). Lipodystrophy is a common side effect of highly active antiretroviral therapy (HAART).
Microbicide
A product that, when applied topically, is able to prevent the sexual transmission of HIV or other sexually transmitted diseases.
Monotherapy
A treatment strategy in which only one drug is administered, instead of multiple drugs in combination. This strategy is often used to reduce drug toxicity and to address or avoid side effects.
Non-nucleoside reverse transcriptase inhibitor (NNRTI)
A class of antiretroviral drug that inhibits the action of reverse transcriptase, one of the enzymes HIV needs to make copies of itself. Unlike another class of drug called NRTIs, NNRTIs are not effective against the type of HIV known as HIV-2.
Nucleoside/nucleotide reverse transcriptase inhibitor (NRTI/NtRTI)
A class of antiretroviral drug that blocks the action of reverse transcriptase, one of the enzymes HIV needs to make copies of itself.
Open lable
A clinical trial in which researchers and participants know who is receiving the experimental drug.
Opportunistic infection
An illness such as Pneumoncystis carinii pneumonia (PCP) that people with HIV/AIDS can get and which can be potentially life-threatening. People with healthy immune systems do not usually get these illnesses, even though most people already have the organisms that cause these illnesses in their bodies. When the immune system is damaged, the organisms take advantage of the “opportunity” to cause illness.
Placebo
An inactive substance against which an experimental treatment is compared. A placebo looks, smells and tastes like the treatment being substituted, but has no active agent in it. It is sometimes called a “sugar pill.”
Preventative vaccine
A vaccine designed to prevent a disease in a person by producing or artificially increasing immunity.
Protocol
The detailed, written plan for a clinical trial that includes all relevant information about the trial, including the trial’s rationale, purpose, drug dosages, length of treatment, how the treatment is given, who may participate (inclusion/exclusion criteria), criteria for determining the trial’s success or failure, and the methods of data analysis and interpretation. Research ethics boards and Health Canada must approve the protocol before a clinical trial can begin.
Protease inhibitor
A class of antiretroviral drug that interferes with the replication of HIV by inhibiting the HIV enzyme called “protease.”
Provincial formulary
A list of the treatments that are covered by a provincial government’s funding plan.
Randomized trial
A trial in which participants are assigned to one of the study treatment groups randomly (as by the flip of a coin). Usually a computer is used to randomly allocate participants to the arms of such a study. This helps remove any bias when deciding which participants receive a particular treatment.
Research ethics board(REB)
An independent committee established to protect the rights and interests of clinical trials participants. REBs are sometimes called Institutional Review Boards (IRBs), Ethics Review Boards or just Ethics Boards. Every institution or hospital that conducts human research must have its own REB (also called Institutional Review Board (IRB)).
Retrovirus
A type of virus that has RNA instead of DNA as its genetic material. It uses an enzyme called reverse transcriptase to become part of the host cells’ DNA. This allows many copies of the virus to be made in the host cells. The virus that causes AIDS, the human immunodeficiency virus (HIV), is a type of retrovirus.
Roll-over trial
A trial that only includes volunteers who participated in previous trials for the experimental agent in question.
Screening
The process whereby potential volunteers are assessed as to whether or not they meet the entry criteria of the trial. Screening generally precedes enrolment into the trial.
Side effects
Resulting actions or effects of a treatment that are other than those desired. Usually refers to undesirable or negative effects. Experimental treatments must be evaluated for both immediate and long-term side effects. Long term side effects are often referred to as toxicities.
Special access programme (SAP)
Health Canada can authorize a manufacturer to release any drug that has not yet been approved for sale in Canada on an emergency basis – including drugs in clinical trials. To apply for an un-licensed drug through the SAP, you must ask your doctor to contact the programme. Pharmaceutical companies do not have to provide the drug, and there may be a cost decided on by the company.
Standard-of-care
A diagnostic and treatment process that a clinician should follow for a certain type of patient, illness, or clinical circumstance. Also called standard therapy or best practice.
Structured treatment interruption (STI)
A temporary suspension of treatment, planned in consultation with a physician.
Study group
See arm.
Surrogate markers
A surrogate is a substitute. If something under study is not readily measurable because it takes a long time to show up, researchers may use a surrogate marker to predict the eventual measurement. Surrogate markers in HIV research are important because the effectiveness of drugs in slowing down HIV disease progression or increasing survival may not be obvious for many years. Common HIV surrogate markers include CD4 count and viral load.
T-cell
One type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells. T cells also produce a number of substances that regulate the immune response.
Therapeutic vaccine
A vaccine designed to boost the immune response to HIV in people already infected with the virus.
Therapy
Any drug or other treatment intended to control symptoms of a condition, side effects or toxicities, or to relieve or cure a disease or illness.
Toxicity
The unwanted effects or damage caused by a drug.
Treatment
A form of therapy, often a drug, used to control symptoms of a condition, side effects or toxicities, or to relieve or cure a disease or illness.
Treatment arm
See arm.
Treatment interruption
See structured treatment interruption.
Vaccine
A substance that teaches the body’s immune system to recognize and/or protect against a disease caused by an infectious agent (virus or bacteria).
Viral load
The amount of HIV virus in the blood.
WASHOUT PERIOD
A period during which participants do not take certain drugs, so that all traces of those drugs can be washed out of the body.
White blood cell
A type of cell in the immune system that helps the body fight infection and disease.