McCormack says the data mark the end of the road not just for this vaginal gel but the whole class
of microbicides that use nonspecific compounds to prevent HIV - infection.
The largest study ever conducted
of a microbicide designed to prevent HIV infection has resulted in yet another case of high hopes being dashed about a promising product.
Not exact matches
A series
of vaccine and
microbicide clinical trials to prevent HIV transmission have been unsuccessful, and scientists are returning to the drawing board to devise new approaches.
Researchers leading a large, ongoing study in women called VOICE that compares PrEP with pills to a vaginal
microbicide plan to revaluate the ethics
of continuing to use a placebo control group given the new evidence
of oral Truvada's powerful impact.
As reported online this week in Science and in a presentation at the 18th International AIDS Conference in Vienna,
of the 444 women who received a placebo gel, 60 became infected with HIV versus 38 infections in the 445 women who received the
microbicide.
Another application could be their development into crèmes or gels (i.e.
microbicides) that prevent transmission
of viruses like HIV during sexual intercourse.
That $ 90 million study, financed by the U.S. National Institutes
of Health (NIH), startled many in the field who, based on other failures
of nonspecific
microbicides, had predicted the product would do nothing.
The U.S. National Institute
of Allergy and Infectious Diseases provided the main funding for ASPIRE, which was run by the
Microbicide Trials Network that Hillier heads.
But the most promising candidates — compounds called vaginal
microbicides that thwart the virus at the site
of infection — have failed repeatedly in clinical trials.
«This [set
of studies] was the last hope for
microbicides in many ways,» says Thomas Hope
of Northwestern University's Feinberg School
of Medicine in Chicago, Illinois.
Where budgets are limited, they suggest money should be allocated first to increasing male circumcision, then to more frequent HIV screening, use
of vaginal
microbicides and increasing antiretroviral therapy.
These include voluntary male circumcision — now recommended by the World Health Organization and Joint United Nations Programme on HIV / AIDS as a preventive strategy — as well as vaginal
microbicides and oral pre-exposure prophylaxis, all
of which confer only partial protection against HIV.
«I'm very pleased that the answer was so clear,» says the University
of Pittsburgh's Sharon Hillier, who heads the
Microbicide Trials Network that is conducting VOICE.
Rhesus macaques like this one blocked the monkey version
of HIV with a new
microbicide.
The failure
of first - generation
microbicides has led the field to largely abandon the strategy behind them: that HIV could be stopped by compounds, such as soaps, that disable the virus without specifically attacking it.
In addition to the expanded use
of ARVs in new modalities such as pre-exposure prophylaxis and
microbicides [1], this includes commensal
microbicides [2], gene therapies [3], [4] and vaccines [5], [6], [7].
Funding: This work was supported by the European Commission sixth Frame Work Programme as part
of the European Vaccines and
Microbicides Enterprise (EUROPRISE), the European Commission seventh Frame Work Programme as part
of the Combined Highly Active Anti-retroviral
Microbicides project (CHAARM)[to RAW], the Bill and Melinda Gates Foundation as part
of the Collaboration for AIDS Vaccine Discovery (CAVD grant 38637 [to RAW] and grant 1032144 [to MSS]-RRB-, and the UK Medical Research Council [RAW and AF].
Janssen GPH will also prioritise work with the International Partnership for
Microbicides developing the investigational drug dapivirine for use as a monthly vaginal microbicidal ring designed to prevent sexual transmission
of HIV and continue its pact with Drugs for Neglected Diseases initiative for the preclinical research
of a reformulated form
of flubendazole for lymphatic filariasis (elephantiasis) and onchocerciasis (river blindness), Janssen GPH is also developing a new, chewable formulation
of Vermox (mebendazole) that will facilitate treatment
of intestinal worms in younger children.
His contributions to
microbicides for HIV prevention spans two decades and culminated in the CAPRISA 004 tenofovir gel trial which provided proof -
of - concept that antiretroviral drugs can prevent sexually transmitted HIV infection and herpes simplex virus type 2 in women.
Among other grants, he has participated to several EC - FP6 funded grants (AVIP, NEAT, Europrise) and coordinated the «GISHEAL» program on the genetics and immunology
of HIV long term nonprogressors; he has also participated to the FP7 - funded project «AIM - HIV» on
microbicide discovery.
Professor Abdool Karim is a member
of the UNAIDS Scientific Expert Panel and Scientific Advisor to the Executive Director
of UNAIDS, Scientific Advisory Board member
of the US President's Emergency Pan for AIDS Relief (PEPFAR), Chair
of the PEPFAR Adolescent Girls and Young Women Expert Working Group, a member
of the HIV Centre Strategic Advisory Committee and the NIH OAR
Microbicides Planning Group.
Syncytium inducing phenotype (MT2): NSI Coreceptor use: R5 X4 Titration
of infectivity (TCID50 / ml): 10e6.6 SUBTYPE: F1 This isolate is part
of an European Panel
of HIV - 1 isolates form the Network
of Excellence European Vaccines and
Microbicides
The ongoing Cape Town congress is itself a sign
of change, aimed at bringing together researchers pursuing their different aims in vaccines, pre-exposure prophylaxis, and
microbicides along with community members, policymakers, and advocates.
Syncytium inducing phenotype (MT2): NSI Coreceptor use: R5 Titration
of infectivity (TCID50 / ml): 10e5.2 SUBTYPE: B This isolate is part
of an European Panel
of HIV - 1 isolates form the Network
of Excellence European Vaccines and
Microbicides Enterpri
Restricted to use by members
of the European Vaccines and
Microbicides Enterprise and for use within Europe.
Shattock himself is currently undertaking research into the potential effects
of combining a
microbicide and an experimental vaccine candidate.
Syncytium inducing phenotype (MT2): NSI Coreceptor use: R5 Titration
of infectivity (TCID50 / ml): 10e5.4 SUBTYPE: BF1 This isolate is part
of an European Panel
of HIV - 1 isolates form the Network
of Excellence European Vaccines and
Microbicides Enterpr
Syncytium inducing phenotype (MT2): NSI Coreceptor use: R5 Titration
of infectivity (TCID50 / ml): 10e6.2 SUBTYPE: F1 This isolate is part
of an European Panel
of HIV - 1 isolates form the Network
of Excellence European Vaccines and
Microbicides Ent
Syncytium inducing phenotype (MT2): NSI Coreceptor use: R5 Titration
of infectivity (TCID50 / ml): 10e5.2 SUBTYPE: F1 This isolate is part
of an European Panel
of HIV - 1 isolates form the Network
of Excellence European Vaccines and
Microbicides Enterpr
James Eghaghe The New HIV Vaccine and
Microbicide Research Advocacy Society
of Nigeria (NHVMAS), Nigeria
Interim data from a parallel open - label study
of the ring called HOPE, led by the US National Institutes
of Health - funded
Microbicide Trials Network (MTN), reported nearly identical results today at CROI.
Pilar received her PhD in 2017 at the Complutense University
of Madrid, where she studied immune cell dysfunction and hyperactivation in HIV / HCV coinfected patients, as well as the in vitro and in vivo activity
of nanoparticles against HIV - 1 and HSV - 2 infections to prevent their transmission in humans as a topical
microbicide.
We tried to address some
of these issues while working on an RNAi - based
microbicide to prevent sexual transmission
of viral infection (and ultimately HIV) in mice.
Researchers from the University
of Nebraska - Lincoln have generated an «on - off switch» into a weakened form
of HIV, potentially creating a new vaccine for Comprehensive exploration
of research into HIV prevention, including
microbicides, PrEP, PEP, condoms, circumcision and HIV treatment as prevention.
Learn about HIV prevention Comprehensive exploration
of research into HIV prevention, including
microbicides, PrEP, PEP, condoms, circumcision and HIV treatment as prevention.