HIV Therapy With Remune(TM) Appears to Reconstitute Helper T-Cell
Responses Against the Virus in Patients on Antiviral Drug Therapy
Research Supports Synergism Between Remune and Antiviral Drugs
CARLSBAD, Calif., Apr 13, 2000 /PRNewswire via COMTEX/ -- The Immune Response
Corporation (Nasdaq: IMNR) announced today that Remune(TM) (HIV-1 immunogen),
its potential immune-based therapy for the treatment of HIV infection, appears
to boost CD4 helper T-cell (immune cell) activity against HIV in chronically
(long-term) infected patients on antiviral drug therapy. HIV-specific immune
responses typically decline during the course of HIV infection despite treatment
with antiviral drugs, and the ability to enhance such responses may represent an
additional strategy to long-term control of HIV infection. This research,
published in the current issue of "AIDS Research and Human Retroviruses,"
represents a collaborative effort with researchers at Becton Dickinson (NYSE:
BDX) who measured the immune cell responses against HIV.
"Despite the potency of antiviral drug therapy, there is an emerging consensus
in the scientific community that boosting the immune system's natural ability to
recognize and fight HIV may be the key to long-term control of HIV infection.
However, it has been reported that certain immune responses against HIV, in
particular HIV-specific CD4 helper T-cell activity, actually decline with the
prolonged suppression of the virus that is associated with antiviral drug
therapy," said Dr. Ronald B. Moss, Vice President of Medical and Scientific
Affairs at The Immune Response Corporation. "In the published study, we report
that treatment with Remune appears to reconstitute HIV-specific CD4 helper
T-cell responses in patients on antiviral drug therapy. This suggests that the
combination of Remune and antiviral drugs may represent an optimal clinical
strategy for combating HIV."
In the published study, immune cell function was measured in 18 patients with
chronic HIV infection before (baseline) and after quarterly injections of
Remune. Whereas, baseline responses against HIV were undetectable or low in the
group studied before treatment with REMUNE, significant increases, ranging from
3 to 20 fold on average, in CD4 helper T-cell activity specifically against HIV
were detected after treatment with Remune. T-cell activity was assessed using a
very sensitive assay developed by Becton Dickinson that counts the number of CD4
helper T-cells producing intracellular cytokines, such as interferon gamma,
after the blood sample is stimulated with HIV antigens (proteins from the virus
that are recognized by immune cells and induce an immune response). Cytokines
act as "communications proteins" that orchestrate immune responses.
"The sensitivity of this cytokine-based assay permitted the detection in this
study of very low levels of HIV-specific helper T-cells in patients receiving
potent antiviral drug therapy. Using the same cytokine-based assay, we and other
researchers have shown that already very low levels of CD4 helper T-cell
activity are subject to even further decline in HIV patients on antiviral drug
therapy," said Dr. Vernon Maino, co-author and Scientific Director at Becton
Dickinson. "We observed that individuals with suppressed viral load at baseline
and/or those receiving antiviral drug therapy had the best CD4 helper T-cell
activity after Remune therapy. The T helper immune responses to REMUNE were
quite robust, as measured by our assay, and were comparable to those observed in
clinical non-progressors."
This research may support the ongoing clinical trials of REMUNE in combination
with antiviral drugs in the long term treatment of HIV infection. |
