PARIS--(Marketwire - October 21, 2009) -
EMBARGOED FOR RELEASE UNTIL 2:00pm CEST, or 8:00am
USA EST -- Abstract #173886 -- An immunological analysis of a Phase II
clinical trial demonstrated that the therapeutic peptide-based HIV vaccine
Vacc-4x increased T-cell counts in chronically infected HIV patients.
Because 15 to 20% of all HIV positive individuals are not able to achieve
increased
T-cell counts through antiretroviral therapy(1), Vacc-4x may provide a
viable alternative. The research was presented today as part of a late
breaking poster at AIDS Vaccine 2009, the annual meeting of the Global HIV
Vaccine Enterprise, in Paris.
"We are very pleased to continue to investigate Vacc-4x's effect,
especially its ability to help HIV positive individuals with low CD4
counts, because these people have no effective treatment options," said
Per Bengtsson, MD, PhD, Senior Vice President, Development and Chief
Medical Officer, Bionor Immuno, makers of the investigational vaccine.
"This is clearly a group with an unmet medical need, and we're pleased to
pursue therapeutic alternatives."
Bionor Immuno is in the process of initiating a new Vacc-4x program that
seeks to help people with HIV who do not respond adequately to available
treatments. In a Phase II trial with Vacc-4x, a synthetic and specific
peptide vaccine to HIV-1 p24Gag, the increase of CD4 cells was studied in
37 chronically infected HIV patients on antiretroviral therapy (ART) and
with varying baseline CD4 T-cell counts. The median duration of ART prior
to Vacc-4x immunization was 4.5 years and pre-ART CD4 counts were median
295 cells/uL.
The average increase of CD4 counts was 9% (P < 0,05) above baseline at 585
cell/uL (mean) 12 weeks after the start of immunization. For patients with
baseline CD4 level < 500 cells/uL (n=11) the increase was 25% (P < 0,05) or
105 cells/uL. Patients on ART immunized with Vacc-4x experienced increased
CD4 counts. The effect appeared more pronounced in patients with lower
baseline CD4 counts ( < 400-500). In a previous study (ACTG 384) CD4
increase for patients (pre-ART CD4 < 300) was minimal after 120 weeks on
ART.(2)
Since its implementation more than a decade ago, combination antiretroviral
therapy (ART) has had a dramatic effect on the morbidity and mortality of
HIV-1 positive individuals. However, 15 to 20% of the patients initiating
ART do not regain CD4 T-cells despite an effective suppression of
HIV-1-mRNA levels in blood. The incomplete therapeutic effect leaves these
patients at increased risk of disease complications and death. Attempts to
reduce clinical events through IL-2 induced stimulation of CD4 T-cells in
the ESPRIT and SILCAAT studies proved to be unsuccessful.
About Vacc-4x
Vacc-4x is an HIV-1 immunotherapeutic vaccine comprised of synthetic
peptides corresponding to conserved domains on the major core HIV-1 p24
capsid protein. Safety and tolerability have been confirmed in
HIV-1-infected subjects following intradermal immunization schedules
without serious adverse events.
As a therapeutic vaccination, it evoked strong, dose-dependent immune
responses in a Phase IIa clinical trial, as determined by CD4+ and CD8+
T-cell proliferative responses as well as the intradermal skin test delayed
type hypersensitivity (DTH). The response was sustained for the
observation period of four years after immunization. CD4+ counts were
increased in all patients after immunization and increases were more
pronounced in those patients that had lower baseline CD4+ counts.
About Bionor Immuno
Bionor Immuno is an innovative biotech company developing synthetic peptide
vaccines that stimulate cell-mediated immunity. Previous efforts made to
use T-cell stimulation for vaccines have been notoriously unsuccessful and
this is the reason they are not on the market today. Bionor Immuno
carefully designs synthetic (modified) peptides with improved efficacy and
safety profiles. Among the diseases targeted are chronic infections caused
by HIV, Hepatitis C (HCV), Human Papilloma Virus (HPV) and Influenza.
Bionor Immuno's platform technology is universally applicable and makes it
possible to extend the range of projects to include vaccines targeting
cancer.
(1) Robbins CID 2009, 48, 350-361
(2) Ibid.
