By David Miller
Tens of thousands of people in the United States are living with strains of HIV that have become resistant to some, or all, of the available HIV antiretrovirals. HIV drug-resistance can occur by taking ARV’s improperly or by the natural evolution of resistance mutations. Resistant strains of HIV can be transmitted. Consequently, one can be resistant to drugs they have never taken, simply because they were taken by the person from whom they were infected by. This phenomenon is called “transmitted HIV drug resistance.”
Not enough attention is being given to finding new drugs that can help people who are resistant to some, or all, of the HIV medications. People are dying because they have run out of HIV medications that work for them. This reality is not acceptable, and the situation is getting worse.
At CROI (Conference on Retroviruses and Opportunistic Infections) 2013, the CDC (Centers for Disease Control) reported the latest statistics on transmitted HIV drug resistance. It was reported that the overall rate of transmitted drug resistance has stayed virtually the same at 16%, versus 15% in 2007. However, transmitted drug resistance to one class of ARVs, NNRTIs (the second class of HIV ARVs to be FDA approved) is rising annually at an estimated 5.2%.
This study shows the importance of developing new drugs with good resistance profiles (different mutations that confer resistance).
One of these newly developed drugs is Apricitabine (ATC). A phase III NRTI, Nucleoside/Nucleotide Reverse Transcriptase Inhibitor), ATC is very close to receiving FDA approval, pending one more clinical trial to generate the data for FDA approval. ATC will hopefully be made available soon for treating treatment-experienced, drug-resistant HIV patients.
ATC has been shown to be safe and effective. ATC is chemically very similar to Lamivudine (found in Epivir, Combivir and Trizivir) and Emtricitabine (found in Emtriva, Truvada and Atripla). It was designed to work against HIV that has become resistant to Lamivudine and Emtricitabine.
In a 96-week phase III clinical trial, 87% of participants maintained undetectable HIV levels through the course of the treatment. Researchers also saw continued CD4 increases in patients while on ATC. There were no ATC-related Serious Adverse Events and no withdrawals from the trial due to side-effects associated with ATC. Additionally, no signature mutations were observed after 2 years on treatment.
ATC is desperately needed for patients who are resistant to other NRTI’s.