CMX157 is a lipid (1-0-hexadecyloxypropyl) conjugate of the acyclic nucleotide analog tenofovir (TFV) with activity against both wild-type and antiretroviral drug-resistant HIV strains, including multidrug nucleoside/nucleotide analog-resistant viruses. CMX157 was designed to mimic lysophosphatidylcholine to take advantage of natural lipid uptake pathways and to achieve high intracellular concentrations of the active antiviral, with the aim of increasing the effectiveness of TFV against wild-type and mutant HIV. CMX157 demonstrated potential to effectively suppress replication of multiNRTI-resistant (MNR) HIV that cannot be treated with any currently available NRTIs, including TDF. It is in phase II clinical trial for HIV infections in USA and phase Ib portion of the phase I/II trial for Hepatitis B in Thailand (PO).

Efavirenz (brand names Sustiva® and Stocrin®) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) and is used as part of highly active antiretroviral therapy (HAART) for the treatment of a human immunodeficiency virus (HIV) type 1. For HIV infection that has not previously been treated, efavirenz and lamivudine in combination with zidovudine or tenofovir is the preferred NNRTI-based regimen. Efavirenz is also used in combination with other antiretroviral agents as part of an expanded postexposure prophylaxis regimen to prevent HIV transmission for those exposed to materials associated with a high risk for HIV transmission.

CMX157 is a lipid (1-0-hexadecyloxypropyl) conjugate of the acyclic nucleotide analog tenofovir (TFV) with activity against both wild-type and antiretroviral drug-resistant HIV strains, including multidrug nucleoside/nucleotide analog-resistant viruses. CMX157 was designed to mimic lysophosphatidylcholine to take advantage of natural lipid uptake pathways and to achieve high intracellular concentrations of the active antiviral, with the aim of increasing the effectiveness of TFV against wild-type and mutant HIV. CMX157 demonstrated potential to effectively suppress replication of multiNRTI-resistant (MNR) HIV that cannot be treated with any currently available NRTIs, including TDF. It is in phase II clinical trial for HIV infections in USA and phase Ib portion of the phase I/II trial for Hepatitis B in Thailand (PO).