Eric Sawyer, age 62, a long-term HIV activist and consultant at the New York City-based GMHC, knows all too well the toll that these lifesaving medications can take on the body. Sawyer started developing symptoms of HIV back in 1981, even before the virus was discovered. At the time, he was told that he wouldn't live to see age 35. Fortunately, he was able to enroll in some of the earliest clinical trials taking place in HIV medical research. He has taken part in testing for a host of HIV drugs over the years.
While these drugs helped save Sawyer's life, some of the drugs he took came with debilitating side effects. One drug played a role in his developing peripheral neuropathy, which causes severe pain in his feet. To this day, Sawyer can't wear regular shoes. Years later Sawyer developed avascular necrosis of the hip. "My hip started to crumble, and I had to have a hip replacement in my 40s and the other hip replaced a couple of years ago."
The development of this type of necrosis can arise from the use of anabolic steroids that physicians often prescribe to people living with HIV to help them to gain weight, or from medications currently being prescribed to treat the disease, said Dr. Bisher Akil, a New York City-based physician who treats Sawyer.
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About five years ago Akil started Sawyer on an antiretroviral medication called Truvada, developed by Gilead Sciences. Today's HIV antiretroviral drug regimens are taken in pill form, as part of a three-drug treatment regime that work together as a cocktail to block the HIV-virus at different parts of the replication cycle. This approach stops the virus from infecting new cells and allows a patient's T-cell count to replenish. These drugs have proven so successful they can reduce the amount of the HIV virus detectable in the body to a degree that it is no longer measurable by a blood test.
Truvada worked well for Sawyer, but the medication may also have played a role in causing a severe level of toxicity in his kidneys, which left untreated can result in renal failure. To stop the elevation of serum creatinine levels in Sawyer's blood, which was causing damage to his kidneys, Akil took Sawyer off Truvada and replaced it with Gilead's newer version of the drug, Descovy, which received the Food and Drug Administration's approval in April 2016.
Descovy, a combination of the drugs emtricitabine and tenofovir alafenamide (TAF), can be given at a much lower dose than Truvada. Several of Gilead's newer HIV drug therapies, such as Genvoya and Odefsey, contain TAF in place of tenofovir disoproxil fumarate (TDF), which is the main ingredient in Gilead's older HIV drugs — Stribild, Atripla and Complera, as well as Truvada.
TAF has demonstrated that it works as well as TDF-based drugs at less than one-tenth the dosage. It has also demonstrated improvements in renal and bone safety. Patients in a trial on a TAF-based drug had less hip and spine bone loss and more favorable kidney function than those on TDF-based drugs, according to Gilead.
Descovy has an average wholesale price of near-$1,800 a month, similar to Truvada's price, according to pricing information from the National Institutes of Health. Sawyer's doctor said paying for Descovy would be cheaper for the health insurance provider than paying for Sawyer to go on dialysis or get a kidney transplant, which is where Sawyer was headed. After six months on Descovy, Sawyer's kidney function improved.
This switch to newer drugs is beginning to show up in Gilead's results. In its quarterly earnings released last week, overall HIV drug sales increased by 12 percent, to $3.4 billion, in the fourth quarter 2016, even as Truvada sales and sales of other, older TDF-based HIV drugs continued to decline. HIV sales totaled $12.9 billion for the full year 2016, also up from the previous year's level of $11.1 billion.