Bionor Pharma ASA's Therapeutic HIV Vaccine Vacc-4x Improves Quality of Immune Responses in HIV Patients, Resulting in Long-Term Reduction in Viral Load and Potential for Periodic "Boosts" That Could Result in New Treatment Option for People Living With H
Published: Jul 20, 2012
Bionor Pharma researchers present new findings at International AIDS Society's "Towards an HIV Cure" Symposium 20 and 21 July, in Washington
A poster describing immunological data from the large exploratory phase II study with Vacc-4x will be presented. The qualitative difference in immune responses may have contributed to the killing of infected cells leading to a statistical significant reduction in viral load
Bionor Pharma presents its latest vaccine research details to the UNAIDS Ambassador, H.R.H. Crown Princess Mette-Marit at AIDS2012
Bionor Pharma ASA (OSLO: BIONOR) announced today that the Company is presenting its immunological data from the large exploratory phase II study of Vacc-4x at the "Towards an HIV Cure" workshop sponsored by the International AIDS Society, in conjunction with the AIDS 2012 conference, Friday 20 and Saturday 21, July.
The results from further immunological analysis of the phase II data with Vacc-4x show improved quality of immune cells, that can in part explain killing of HIV infected cells leading to the reduction in viral load in patients receiving Vacc-4x.
"This shows that Vacc-4x works differently than ART. If a patient stops taking ART, the virus normally returns within a few weeks, but with Vacc-4x we see a sustained response," said Jürgen Rockstroh, PhD, member of Bionor Pharma's Clinical Advisory Board. "The explanation seems to be that Vacc-4x is inducing an immune response allowing patients' own immune systems to attack the virus for a sustained period of time, and this appears to work for people regardless of their genetic makeup."
Vacc-4x data for presentation at IAS Cure Symposium
The poster describes first that patients in the Vacc-4x group of the randomized, placebo-controlled, double-blind, multinational exploratory phase II study (previously announced 15 Feb. 2012) achieved a statistical significantly lower viral load set point compared to the placebo group. It was therefore important to determine whether the 'quality' of immune responses between the two groups was different. Here, the expression of cytokines (chemical messengers) from CD4 and CD8 T-cells between the two groups (intracellular cytokine assay) were compared.
For all subjects, (both placebo and Vacc-4x) CD8 T-cells expressed higher levels of cytokines than CD4 T-cells.
The CD8+ T cell cytokine responses were, however, significantly increased between baseline and week 52 for the Vacc-4x (all parameters: p values < 0.043), but not for the placebo group (p >0.05, Wilcoxon). The increase over time for the Vacc-4x group suggests a link to immunization with Vacc-4x.
There was a trend towards higher numbers of polyfunctional T-cells in the Vacc-4x group compared to the placebo group. Polyfunctional T-cells (that express more than one cytokine simultaneously) are associated with control of infection.
Subjects were also tested for immunological markers (HLA), although this was not an inclusion criterion. As previously shown, subjects with HLA B27 or B57 generally have better control of the infection, whereas subjects with B35 tend to show faster disease progression (higher viral loads). Notably more subjects randomized to the Vacc-4x group had B35 compared to the placebo group. (Subjects randomized to the Vacc-4x group also had higher pre ART viral loads). Despite this, on immunization with Vacc-4x, the Vacc-4x group achieved a statistically significant improved virus control compared to placebo. Indeed, 30% of subjects in the Vacc-4x group that stayed off ART for more than 1 year had HLA B35 compared to 0% in the placebo group.
Taken together, these findings suggest that the quality of immune responses in the two groups was different.
The qualitative difference in immune responses in the Vacc-4x group may have contributed to the observed statistically significant reduction in viral load.
Vacc-4x can also provide benefit in subjects with HLA B35.
About the International AIDS Society (IAS) and the Cure Symposium The International AIDS Society (www.iasociety.org) is the world's leading independent association of HIV professionals.
By convening the world's foremost international conferences on HIV and AIDS and specialized meetings, they provide critical platforms for presenting new research, promoting dialogue and building consensus to advance the global fight against HIV.
By promoting dialogue, education and networking, and providing access to best practice, professional development and skills building, they help build capacity and close gaps in knowledge and expertise at every level of the HIV response.
By advocating for the right to an evidence-based response to HIV and for a concerted research effort to build that evidence base, they contribute to continuous improvement of the global response to HIV.
The 2-day Cure Symposium linked to AIDS 2012 brings together an international working group of researchers developing a Global Scientific Strategy Towards an HIV Cure. The strategy aims at building a global consensus defining scientific priorities for HIV cure research. Up to 250 leaders from academia, industry, government and community-based groups will take part. The symposium will be co-chaired by Françoise Barré-Sinoussi, 2008 Nobel Laureate for Medicine and IAS President-elect and Steven Deeks, Professor of Medicine at the University of California, San Francisco (UCSF). This symposium will be closely linked to the AIDS 2012 conference programme.
A New Strategy to Eradicate HIV with Vacc-4x
ART is not a cure, and the treatment can cause serious side effects. ART does not kill virus producing cells, and it blocks virus production only while patients take the medication. ART must therefore be a daily, lifelong treatment. In contrast, Vacc-4x is developed to provide long lasting virus control by training immune cells to seek out and kill virus-producing cells, without any serious side effects.
About Bionor Pharma ASA
Bionor Pharma is a leading vaccine company, listed on the Oslo Stock Exchange. The Company's investments in developing therapeutic vaccines exceed US$70 million.
Bionor's vaccines are based on the proprietary technology platform developed following more than two decades of research on peptides. The vaccines are designed to safely stimulate each person's immune system to combat viral diseases. The Company's lead HIV vaccine, Vacc-4x, is being investigated as a therapeutic vaccine, and has completed a large exploratory phase 2 randomized, multinational (USA and 4 European countries), double-blind, placebo-controlled trial. It produced a statistically significant reduction in viral load and viral load set point (stabilized viral load) by killing of virus producing cells.
Bionor's second therapeutic HIV vaccine, Vacc-C5, is developed to induce antibodies to HIV that can reduce viral production (lowering the set point) and the harmful hyperactivation of the immune system that leads to AIDS. Recently, the clinical phase I/II study with Vacc-C5 was approved by the Norwegian Regulatory Authorities. Subsequent to the Vacc-C5 phase I/II trial, Bionor intends to combine Vacc-4x with Vacc-C5, which could form the basis for both a therapeutic and a preventive HIV vaccine.
The Company's innovative technology platform is also well suited to develop vaccines for other viral diseases, including Influenza, HCV (Hepatitis C), CMV (Cytomegalovirus) and HPV (Human papillomavirus). Vaccines for Influenza (Vacc-Flu) and HCV (Vacc-HCV) are in preclinical phase of development.
More information about Bionor Pharma, its research and products, is available at www.bionorpharma.com.
This information is subject of the disclosure requirements acc. to §5-12 vphl
(Norwegian Securities Trading Act). Vacc-4x, Vacc-C5, Vacc-Flu, Vacc-HCV, Vacc-CMV and Vacc-HPV are investigational treatments that have not been approved for marketing by any regulatory authority.
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