2010 & Beyond
BY Benjamin Ryan
November 18 2010 4:00 AM ET
Imagine if you could chuck your daily supply of anti-HIV meds and replace them with a monthly transfusion at your physician’s office or, if possible, even a single shot that you give yourself. A small but determined group of biotech companies are researching new therapies that would last in the body for weeks or longer.
TaiMed Biologics and Progenics Pharmaceuticals, for example, are each looking into drugs known as monoclonal antibodies; these have already revolutionized cancer treatment and have made some chemotherapy far more tolerable when it comes to possible side effects. TaiMed’s agent is an antibody that blocks HIV’s attachment to the CD4 coreceptors. It is made by injecting mice with those same coreceptors, harvesting the natural antibodies the mice produces as a reaction, and then altering the DNA of those antibodies so that they are 99% human. Infused into an HIV patient, these antibodies, it’s theorized, could last up to a month.
Progenics is in clinical trials of PRO 140, a monoclonal antibody that blocks the CCR5 coreceptor. Study results published this year indicated that once-weekly and every-other-week subcutaneous injections of the antibody both suppressed viral loads significantly, and patients could potentially administer the injections themselves. PRO 140 has received fast-track designation from the Food and Drug Administration.
Tibotec Pharmaceuticals, the antiviral division of Johnson & Johnson, is attempting to produce a long-acting version of one of its upcoming nonnukes, currently referred to as TMC278. The medication is processed to create a mixture of tiny particles of TMC278 with a liquid to create a solution called a nanosuspension. When injected into the body this solution works to extend the release of medication over the course of weeks.
Another compound, EFdA, a nucleoside reverse transcriptase inhibitor being developed in academic and National Institutes of Health labs, meanwhile, has shown itself to be extremely powerful in both test-tube and primate studies.
“This new compound is 60,000 times more potent than any other drug that is currently being used to treat HIV,” says Stefan Sarafianos, an assistant professor of microbiology and immunology at the University of Missouri school of medicine. “This compound has a different chemical makeup than other approved therapies and creates an exceptional amount of antiviral activity. It’s activated very quickly and stays long in the body to fight the virus and protect from infection.”
Curiously, the EFdA compound was discovered by a soy sauce manufacturer in Japan that was developing it as a flavor enhancer. The company’s product tests eventually found it had antiviral capabilities. With a half-life of three weeks, EFdA could be taken less often than currently available options. It also has shown potential for use in a microbicide.
But there’s a major question yet to be addressed: Can researchers develop enough of these long-lasting medications to piece together a viable full cocktail? After all, currently successful combination therapies contain at least three compounds -- whether in the form of three drugs taken together or combo pills taken with one or more additional meds -- since each attacks HIV in different points of the infection cycle.
That’s not to say, though, that they won’t have their benefit. “I see these long-acting drugs as a potential answer to adherence problems,” says Jeffrey Jacobson, the cochair of the long-acting drug task force for the AIDS Clinical Trials Group.
With this type of treatment breakthrough possibly becoming available in the next few years, HIV Plus decided to check in with experts to see what other advancements they think could be in store for HIVers over the decade ahead. And of course, we’re looking at the current traditional treatments that are working their way through clinical research.