March 21, 2012
If you haven't had many opportunities to attend HIV-related conferences, you might wonder just what happens at these gatherings. Four women in our community wrote about their experiences at various conferences over the past year, and shared some of the information they gathered. This is one of those accounts.
Over the past few years our knowledge of HIV and HIV treatment has advanced quickly to create several paradigm shifts in our efforts to treat and prevent HIV. The search for a functional cure offers hope for an end to 30 years of the AIDS crisis. Treatment as prevention and PrEP (pre-exposure prophylaxis) potentially offer individual prevention strategies where affordable and appropriate. Novel research of how HIV affects the immune system, organs and bodies of people with HIV may show us how to limit the devastating short- and long-term effects of the virus. The reemergence of the study of immune-based therapies may present methods to control the immune system's response to the virus and limit inflammation.
The National Association of People With AIDS sponsored a treatment forum at last summer's 6th IAS Conference on HIV Pathogenesis, Treatment and Prevention, presenting novel research that is largely overlooked by the HIV medical and activist community, but holds widespread potential.
In this day and age, it's often possible to observe a conference from afar on a computer screen through online abstracts, slides and even videos of many of the presentations. This forum and conference, for instance, took place in Rome, Italy, but the organizers provided ample information for people like me who were following the conference from offsite.
The forum, organized by NAPWA and AIDS treatment activists, was led by longtime activist and Treatment Education Coordinator at Health People in the Bronx, New York, David Miller. Mr. Miller received an award for his work as a treatment activist and his longtime dedication and unwavering hard work in fighting the AIDS crisis and supporting novel drug development. According to Miller:
The therapies presented at the NAPWA Treatment Horizons Satellite Symposium represent some of the most promising advances in the art and science of antiviral research. From the initiation of this community-driven series of presentations by NAPWA at the 18th IAC, the goal has been to afford every opportunity to provide researchers, policy makers and activists, the often overlooked clinical developments by small biotech companies in finding new therapeutic approaches to HIV and associated complications that affect PLWH/A's globally.
There are many unanswered questions about HIV, its effects and how to stop or slow the virus. Efforts such as this satellite symposium are vital to HIV research as they familiarize us with research and therapies in development which may not be receiving the types of support necessary for conclusive investigation and advancement of promising therapeutic options.
Readers should be aware that many of the following study summaries are highly clinical in nature.
Inflammation continues to occur in people with HIV despite viral suppression and increases in CD4 counts with the use of antiretrovirals (ARVs). Inflammation is believed to be the cause of many non-AIDS-related conditions that people with HIV both on and off ARVs are experiencing such as cardiovascular, bone, kidney and liver disease and neuro-cognitive disorders. Many drugs and compounds are being studied to see if they can reduce the amount of inflammation associated with HIV.
Tobira Therapeutics is looking at its dual chemokine antagonist as a means of lowering inflammation in addition to achieving viral suppression. Cenicriviroc (TBR-652) is a dual chemokine antagonist in Phase IIb clinical development. Cenicriviroc is a once-a-day therapy that may be well suited as a fixed-dose combination. Its unique CCR5/CCR2 dual activity has the potential for cardiovascular/metabolic benefits to address HIV-associated, inflammation-driven morbidity and mortality.
Previous studies have shown cenicriviroc to be synergistic with other ARV classes, to have a long half life, to be safe and well tolerated as well as produce a 1.8 log reduction in viral load. MCP-1 is the primary ligand for CCR2 and a potent chemo-attractant for monocytes/macrophages. The concentrations of MCP-1 are reduced with cenicriviroc, demonstrating a potential decrease in HIV inflammation.
Protocol 652-2-202 is a Phase IIb randomized, double-blind study presently under way in 150 CCR5-tropic, treatment-naive people in the U.S. and Puerto Rico. This study will measure long-term safety and tolerability, dose selection and viral load suppression at 24 weeks. Secondary endpoints include tropism changes, drug resistance in patients with virologic failure, change from baseline in inflammatory biomarkers and immune function at weeks 24 and 48 and change from baseline in metabolic parameters at weeks 24 and 48. Cenicriviroc will be measured at 100 mg with Truvada (tenofovir/FTC) and at 200 mg with Truvada against 600 mg of Sustiva (efavirenz, Stocrin) and Truvada. Cenicriviroc shows potential in changing the way HIV is treated by addressing not only viral replication but inflammation as well.
Vacc-4x is a peptide-based therapeutic vaccine which in previous clinical trials showed an extended period of time off HAART. The latest phase IIb trial did not show the same results but demonstrated a statistically significant treatment difference in viral load compared to placebo among patients who achieved a six-month ART-free period and a decrease in viral load set points (viral load before the initiation of HAART).
According to Maja Sommerfelt, Ph.D., senior vice president and chief scientific officer at Bionor Pharma ASA, Vacc-4x is designed to target immune responses to conserved domains of p24 since sustained immune responses to p24 have been shown to be associated with delayed disease progression. Read the latest news on Vacc-4x.
MARCH 2012 UPDATE: Final analysis of the Phase IIb study confirmed a 60 percent decrease in viral load set points.
According to the Bio Pharma website, a new study is planned in conjunction with Revlimid, a cancer drug. The study will measure Vacc-4x's ability to improve immune function on HIV positive people with CD4 cells between 250 400 despite successful ARV treatment, as well as Revlimid's ability to boost the effect of Vacc-4x.
No information as to when this study will begin enrollment is available.
Another promising therapeutic in this class is Pennvax-G, a phase I HIV therapeutic vaccine. An NIH-sponsored clinical trial found Pennvax-G produced potent antigen-specific T-cell responses. This agent utilizes a new form of vaccine delivery called Electroporation. Electroporation delivers the vaccine to the cell in a more effective, productive manner. A second NIH-sponsored trial is pending.
Purging HIV from latent reservoirs is an area of great interest as a potential functional cure, achieved by activating HIV in resting cells and killing them off with HAART. Aphios presented on Bryostatin -1 (APH 0812) with which they will be initiating trials on HIV latency in Spain. In vivo, Bryostatin revealed antiviral activity against R5- and X4-tropic viruses in receptor independent and partly via transient decrease in CD4/CXCR4 expression. Bryostatin at low nanomolar concentrations also robustly reactivated latent viral infection in monocytic and lymphocytic cells. Bryostatin provoked T-cell reactivation making it a compound worth much further investigation and attention.
Also a therapeutic vaccine, VRX-1273 has thus far been studied in monkeys to ascertain whether it can be utilized to eliminate virus in sanctuary regions. VRX-1273 is made with a lentiviral vector with HIV's genetic material gag, pol and rev inside. When introduced into the immune system, VRX-1273 provokes an immune response to HIV which results in activating CD4 and CD8 cells, lowering the amount of HIV present.
A simian analog of VRX-1273 was given to five macaque monkeys before they were infected with SIV. Two of the five monkeys were functionally cured' with an undetectable viral load in the blood and very low levels of the virus in the lymphatic and intestinal reservoirs. Phase I clinical trials in humans are expected to take place over the next 12 to 15 months.
HIV infection causes immediate damage to the gut during acute infection with a mediated loss of Th17 cells, impairment of mucosal integrity and the innate defense mechanisms. It is known that microbial translocation correlates with chronic immune hyper-activation. Could maintaining a healthy gut be key to reducing the pathogenic potential of HIV due to compromised flora and subsequent barrier disruption resulting in elevation in inflammation? Can probiotics help to maintain a healthy gut, resulting in decreased damage to the immune system by HIV infection?
Fifty percent of HIV-positive people develop gastrointestinal (GI) symptoms, and many more develop GI complications. Bio-K+ probiotics was presented as a means of controlling common problems such as diarrhea, malabsorption, abdominal pain and weight loss, as well as certain conditions. These conditions include villous atrophy (when the villi on the walls of the stomach erode and leave a flat surface), dysphagia (difficulty and/or pain when swallowing) and odynophagia (painful swallowing in the mouth or esophagus which can be caused by esophageal candidiasis or immune disorders).
Bio-K+ probiotic formula contains two forms of friendly bacteria: Lactobacillus acidophilus CL1285® and Lactobacillus casei LBC80R®. These forms of bacteria help to rid the gut of harmful bacteria which cause infection and GI problems, by repopulating the gut with good bacteria which then diminish the bad by competing for nutrients.
Several clinical studies showed Bio-K+ to help clear diarrhea, particularly antibiotic-associated diarrhea (AAD) as well as Clostridium Difficile Associated Disease (CDAD). CDAD is a disease which causes diarrhea and other intestinal conditions such as colitis, which is characterized as inflammation of the colon and results in tenderness, pain, bleeding and fever. Bio-K+ was found to reduce AAD by 56 percent as well as significantly reduce abdominal pain, bloating, liquid stools and ileus (bowel obstruction).
In this presentation it was proposed that probiotics could aid in drug absorption which in turn could reduce drug resistance. By reducing the common GI side effects of many ARVs, compliance to HIV drug regimens would likely increase. Data presented at the 5th IAS conference on HIV Pathogenesis, Treatment and Prevention in 2009 showed the important role of the gut in HIV pathogenesis. This presentation presented many logical arguments for the use of probiotics and the study of the effects they could have not only on the gut but on HIV itself.
"Bio-K+ has demonstrated its capacity to restore the intestinal mucosa and prevent damages from pathogenic microorganisms, and could be an important factor in controlling such damage to the gut and immune system by HIV infection," stated Mathieu Millette, Ph.D., director of fundamental research for Bio-K+ International, Inc.
MARCH 2012 UPDATE: More interesting research on probiotics and HIV is ongoing. The AIDS Healthcare Foundation is studying the ability of another probiotic, Bacillus coagulans GBI-30, 6086 (made by Ganeden) to reduce inflammation resulting in an increase in CD4 cells and a decrease in the proliferation of HIV. Another study on probiotic supplementation was presented at the Conference on Retroviruses and Opportunistic Infections in early March.
Jeannie Wraight has been an HIV treatment advocate for over 14 years. She has attended more than 75 HIV conferences around the world and writes for several HIV publications.
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