IC50 / IC90

The concentration of a drug needed to inhibit viral replication by either 50% (IC50) or 90% (IC90). IC stands for 'inhibitory concentration'.

idiopathic

(id-ee-o-pa-thick)

Disorder whose cause is unknown.

immune modulator

A substance that changes an aspect of the way the immune system is working.

immune reconstitution

Improvement of the function of the immune system as a consequence of anti-HIV therapy.

immune system

The body's mechanisms for fighting infections and eradicating dysfunctional cells.

immunoglobulin

(i-mune-o-glob-you-lin)

Another name for antibodies.

immunologic response

The effect of treatment on the immune system, particularly on the CD4 cell count.

immunosuppression

(i-mune-o-su-pre-shun)

A reduction in the ability of the immune system to fight infections or tumours.

in utero

(in you-ter-row)

Latin term meaning in the womb.

in vitro

(in vee-tro)

Latin term for experiments conducted in artificial environments, e.g. in test-tubes.

in vivo

(in vee-vo)

Latin term for experiments conducted in humans or animals.

inclusion criteria

The conditions which a person must meet to join a clinical trial.

informed consent

Agreement to take part in a clinical trial, or to take a test, after a full written or verbal explanation of the trial including the risks and benefits of taking part, has been provided by the researchers.

insomnia

(in-som-nee-uh)

Sleeplessness.

insulin

(in-syoo-lin)

A hormone produced by the pancreas that tends to lower blood sugar levels.

integrase

(in-te-graze)

HIV enzyme that the virus uses to insert its genetic material into that of an infected cell.

intention to treat analysis

A form of statistical analysis of clinical trials, where data from all participants enrolled in the trial is evaluated, rather than data only from those who complete the trial.

interferon

(in-ter-fear-ron)

A type of antiviral protein which stimulates the immune system.

Interleukin

(in-ter-loo-kin)

A type of cytokine.

intramuscular

(in-truh-muss-kew-lah)

Injected into a muscle.

intrapartum

(in-truh-par-tum)

During the birth of a baby.

intravenous

(in-truh-vee-nuss)

Injected into a vein.

intravitreal

(in-truh-vit-tree-ull)

Injected into the eye.

invasive

In medical terms, going inside the body.

isosporiasis

(eye-so-spor-ry-uh-siss)

An illness caused by the parasite Isospora belli.