Fact Sheet Number 404
NEW CLASSES OF DRUGS
- ATTACHMENT AND FUSION INHIBITORS
- INTEGRASE INHIBITORS
- ZINC FINGER INHIBITORS
- ANTISENSE DRUGS
- DRUGS NO LONGER IN DEVELOPMENT
|
this Fact Sheet on a single page using: |
|
|
|
|
|
More information on Downloading & Printing Fact Sheets |
|
PrintNOTE: Fact Sheets 402 through 405 describe drugs that
are being tested against HIV. See Fact
Sheet 402 for reverse transcriptase inhibitors under development,
Fact Sheet 403 for information
on protease inhibitors, and Fact
Sheet 405 for information on immune stimulators. These drugs
have not been approved by the Food and Drug Administration (FDA)
for use against HIV.
FUSION INHIBITORS
This is a new class of anti-HIV drugs. They are intended to protect
cells from infection by HIV by preventing the virus from attaching
to a new cell and breaking through the cell membrane. Researchers
hope that these drugs can prevent infection of a cell by either
free virus (in the blood) or by contact with an infected cell.
Because digestive acids break them down, most of these drugs
are given by injections or intravenous infusion. Fusion inhibitors
in human trials include FP21399, PRO 542, Schering C, T-20 (enfuvirtide),
T-1249 and TNX-355.
FP21399 by Fuji Pharmaceuticals was tested for safety
in a Phase I trial as a single infusion or a series of 4 weekly
1-hour intravenous infusions. The drug produced viral load decreases
and CD4+ cell increases. Side effects were minor, including blue-tinted
urine and temporary blue marks on the skin. There have been no
recent reports on its status.
PRO 542 by Progenics Pharmaceuticals is in Phase II
trials. It blocks fusion by binding to a protein on the outside
of the virus.
Schering C (SCH-C) by Schering Plough blocks the CCR5
receptor on CD4 cells. It is in Phase I studies. There is some
concern about heart irregularities. Schering has other, related
compounds in development.
T-20 (Enfuvirtide, Fuzeon®) by Trimeris and Roche
is currently in Phase III trials. It can lower viral load even
for patients who have already used many of the approved drugs.
T-20 is injected twice daily. An expanded access program is expected
to open in fall 2002, and the manufacturers plan for approval
in the first quarter of 2003.
T-1249 by Trimeris and Roche is a new fusion inhibitor
drug. It is in Phase I/II trials. T-1249 is effective against
HIV that is resistant to T-20. It stays in the body longer, so
it might require just one injection a day or every other day.
TNX-355 by Tanox blocks the CD4 receptor. It is a genetically
engineered drug, a “monoclonal antibody.” It is in Phase
I trials.
After HIV’s genetic code is changed from a single strand to a
double strand by the reverse transcriptase enzyme, it gets inserted
(integrated) into the genetic code of the infected cell. Then
the HIV genetic code gets “read”, producing new viruses.
Scientists hope that integration will be another point in the
HIV life cycle that can be targeted by drugs.
S-1360 by Shionogi and GlaxoSmithKline is currently
in Phase II trials.
The inner core of HIV is called the nucleocapsid. It is held together
by structures called “zinc fingers”. Zinc finger inhibitors
(or zinc ejectors) are drugs that can break apart these structures
and prevent the virus from functioning.
Scientists believe that the nucleocapsid core cannot mutate
very easily, so a drug that works against zinc fingers might be
effective for a long time. Unfortunately, zinc fingers are not
only used by the HIV virus. Drugs that attack them could have
serious side effects.
One zinc finger inhibitor – azodicarbonamide (ADA) – has been
tested in a Phase I/II trial.
These are a “mirror image” of part of the HIV genetic
code. The drug locks onto the virus to prevent it from functioning.
One antisense drug, HGTV43 by Enzo Therapeutics, is starting
Phase II trials.
IN DEVELOPMENT
AMD3100 by AnorMed
Revised August 5, 2002
Goto InfoNet Main Page
Go toIndex of Fact Sheets
Clickhere if you have questions
New Mexico AIDS Education and Training Center
and the New Mexico Department of Health