However, the simulated results suggest that PI is possibly the best single drug and
fusion inhibitor is the worst drug in terms of viral load and infected cells reduction.
Also, BMS-378806 (21), (23) and Nelfinavir were used as control inhibitors and NB-64 (7) as a Gp41
fusion inhibitor. DMSO plus MT-2 (human, lymphocyte) cells and virus were used to normalize the solvent effect.
All patients were on classical HAART regimens with PIs, NRTIs, NNRTIs; none of the patients received integrase inhibitor, CCR5-receptor antagonist or
fusion inhibitor.
Anti-HIV-1 agents known as
fusion inhibitors target the N-HR or C-HR and disrupt their association, which prevents the virus from entering into the host cell.
Two identical studies, MOTIVATE 1 and MOTIVATE 2, signed up over 1000 HIV-infected people who had tried antiretrovirals from three of four different antiretroviral groups--nucleosides, nonnucleosides, protease inhibitors, and/or the
fusion inhibitor Fuzeon (enfuvirtide).
Primary drug resistance has been reported for all three main classes of antiretroviral drugs: NRTIs, NNRTIs and PIs, and also for the
fusion inhibitor, enfuvirtide (T20).
Fusion inhibitor drugs were introduced for the treatment of AIDS in 2003, and the first saliva-based HIV test was approved by the FDA in 2004.
The
fusion inhibitor already on the market--enfuvirtide, developed in 2003 by Roche and Trimeris under the brand name Fuzeon--has proven effective, but many HIV-positive patients are turned off by its high cost and the fact that it must be injected with a syringe.
Under a range of assumptions about drug costs, the efficacy of therapy and the availability of a
fusion inhibitor (a drug that prevents HIV from entering healthy cells), the current estimated life expectancy varied from 21 to 25 years, and discounted lifetime cost varied from about $330,000 to $400,000.
For these individuals, other new drugs have offered hope, particularly with regimens that include the
fusion inhibitor enfuvirtide, which is the first available agent in a novel class since the development of protease inhibitors.
"The approval of the protease inhibitor darunavir and the
fusion inhibitor enfuviritide ...
reports that ample supplies of the product, also known as enfuvirtide, enable expanded distribution of the drug, the first
fusion inhibitor for the treatment of HIV.