Drug resistance to established regimens can be a major concern. (Photo courtesy of Gilead)
For those living with HIV and fortunate to have access to AIDS drugs, one of the scariest things they face is drug resistance. At some point, they know, their bodies will begin to resist their current drug regimens. This means their doctors will need to find out what‚Äôs happening, when to switch therapies and which drugs to switch to. Then you hope there is no ‚Äúcross resistance‚ÄĚ meaning that an entire class of drugs will be rejected. It‚Äôs a complicated and scary process.
Tragically, if they don‚Äôt switch or other drug regimens aren‚Äôt available or they‚Äôre resistant to other available drugs, as well, eventually they will succumb to AIDS and die. This is the harsh reality of living with HIV: Your options may eventually run out. A recent study estimates more than 76 percent of the U.S. HIV-positive population has some form of drug resistance.
But here is some good news. The Food and Drug Administration just approved a new antiretroviral called Tivicay. The once-daily drug is a class of antiretorvirals known as integrase inhibitors that actually block the virus from entering your immune systems T-cells. Tivicay is the first new treatment delivered by ViiV Healthcare in an HIV joint venture among GlaxoSmithKline, Pfizer and Shionogi in which GlaxoSmithKline is the largest shareholder, with a more than 75 percent stake.
Tivicay can be used to treat infected adults who have been taking other drugs or are new to treatment. So that is some good news in the fight against drug resistance:¬† Now there‚Äôs another treatment option available.
The approval of ViiV‚Äôs Tivicay is important because a number of companies already have or soon will get out of the HIV drug business. One is Roche, which developed the first protease inhibitor many believe saved hundreds of thousands of lives. Some rumors point to Abbott as the next.
Now here is really scary news: Drug resistance is on the rise worldwide, especially in Africa. A recent article in the Daily Nation reports that in Tanzania, around Lake Victoria, patients have stopped taking their HIV drugs. Why?¬† Side effects and drug supplies. In addition, there are reports other African countries have inconsistent HIV drug supplies.
It appears if clinics run out of one or more drugs, they switch their patients to new HIV drug regimens. ‚ÄúAbrupt switches of antiretroviral are threatening our health,‚ÄĚ Samwell Chuma, an HIV patient in Tanzania, stresses, ‚Äúand some new anti-HIV regimens are too strong for our weak bodies to withstand.‚ÄĚ The sad truth is our brothers and sisters in Africa and the rest of the developing world are being given older drugs that many physicians in the United States and in other developed countries would hesitate to prescribe.¬† It’s all about access ‚Äď unfortunately.
The sad reality is we can fight drug resistance only with different, that is, new drugs.
Now let‚Äôs look at the last time a new AIDS drug was approved before the emergence of Tivicay. I emphasize I mean new, and not existing combinations of older drugs contained in one daily pill.
This means we‚Äôve already eliminated two recently approved drugs. One is Gilead‚Äôs drug Stribild, approved a year ago and known by some in the HIV community as the Quad. You can also discount their other combined-in-one pill drugs, Complera, approved in August 2011, and in Atripla, approved in 2006. Good treatments, but not a new drug.
A new drug, Edurant, produced by Janssen, went on the market in 2011. However, Edurant is not approved for patients already using antiretrovirals. Translation? If you are living with HIV now and on an AIDS drug regimen, then you are SOL as it relates to Edurant and, by the way, to some other antiretrovirals available now.
Clinical trials are now underway to explore the use of newly approved Tivicay in a once-daily, fixed dose combination that includes two drugs approved 15 years ago.¬† Looks like ViiV is going to take a chapter out of Gilead‚Äôs game plan:¬† Just combine older drugs into one convenient pill. This is the strategy that allowed Gilead to capture more than half the entire AIDS drug market, which is estimated in the tens of billions of dollars.
Sadly, the last time that Gilead actually had a new drug approved (again, I‚Äôm not including combination drugs in one pill that uses older existing drugs) was August of 2004. That‚Äôs almost 10 years ago. Clearly the trend, if you look at drug approvals over the past six years, is to combine several drugs into one convenient pill. But if we are going to survive this epidemic in the long term, it‚Äôs critical we have new drugs ‚ÄĒ and fast! It could mean the survival of millions of people living with HIV worldwide.