ViiV Healthcare has announced that the U.S. Food and Drug Administration (FDAThe U.S. Department of Health and Human Services agency responsible for ensuring the safety and effectiveness of all drugs, biologics, vaccines, and medical devices, including those used in the diagnosis, treatment, and prevention of HIV infection, AIDS, and AIDS-related opportunistic infections. The FDA also works with the blood banking industry to safeguard the nation's blood supply. The Australian equivalent is the Therapeutic Goods Administration (TGA).) has placed a hold on the development of their new non-nucleoside reverse transcriptase inhibitor (NNRTI), GSK-761.
The reason involves four reports of seizures as part of a clinical trialA clinical trial is a research study to answer specific questions about vaccines or new therapies or new ways of using known treatments. Clinical trials are used to determine whether new drugs or treatments are both safe and effective. Carefully conducted clinical trials are the fastest and safest way to find treatments that work in people. Trials are in four phases: Phase I tests a new drug or treatment in a small group; Phase II expands the study to a larger group of people; Phase III expands the study to an even larger group of people; and Phase IV takes place after the drug or treatment has been licensed and marketed. involving treatment-experienced patients. ‘As a result,’ the company told HIV treatment activists on February 11, ‘the responsible course of action is to put the studies on hold while we gather more information.'
GSK-761 was currently in two Phase IIb studies, including the one in which the seizures were reported. In earlier trials, the drug had shown effectiveness(Of a drug or treatment). The maximum ability of a drug or treatment to produce a result regardless of dosage. A drug passes efficacy trials if it is effective at the dose tested and against the illness for which it is prescribed. In the standard procedure, Phase II clinical trials gauge efficacy, and Phase III trials confirm it. at low once-daily doses, and it was active against strains of HIV that are resistantHIV which has mutated and is less susceptible to the effects of one or more anti-HIV drugs is said to be resistant. to other NNRTIs.
‘This does not mean that the overall development program of GSK-761 has been halted,’ the company added.
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