RFS Pharma LLC

This study is an open-label extension of RFSP-AMDX-2010 study for those subjects who received treatment with amdoxovir (300 mg or 500 mg twice daily) for 12 weeks and benefited from it. This study will examine the safety and efficacy of the investigational HIV drug, amdoxovir (300 mg and 500 mg bid doses; N = up to 30) in combination with zidovudine and lopinavir/ritonavir for 36 weeks.
Subjects will continue to receive either amdoxovir 300 mg twice daily or amdoxovir 500 mg twice daily, each in combination with zidovudine 300 mg twice daily and lopinavir/ritonavir (400 mg/100 mg twice daily) for additional 36 weeks.

This is a double-blind Phase 2a study to test the safety and efficacy of an investigational HIV drug, amdoxovir (300 mg or 500 mg twice daily) compared with tenofovir DF 300 mg once daily in HIV-1 infected antiretroviral therapy-experienced subjects who are currently failing antiretroviral therapy. There are three treatment groups (N=45). Subjects will be randomized to receive either amdoxovir 300 mg twice daily (n=15) or amdoxovir 500 mg twice daily (n=15) or tenofovir DF 300 mg once daily (n=15); each in combination with zidovudine 300 mg twice daily.
The study will assess initially amdoxovir (300 mg or 500 mg twice daily) or tenofovir DF 300 mg once daily, both in combination zidovudine 300 mg twice daily plus failing third drug, but then with lopinavir/ritonavir (400 mg/100 mg twice daily) after Week 2. Subjects who received amdoxovir (300 mg or 500 mg twice daily) and benefited from the drug may choose to enroll in the 36-week open-label study.

The purpose of this study is to determine the short term safety, tolerance, and antiviral effect of zidovudine (AZT) and amdoxovir (AMDX, DAPD) in combination, and whether the dosage for AZT can be reduced, potentially decreasing side effects, while maintaining antiviral effects.
Study hypothesis: DADP in combination with AZT is safe and effective, and AZT dosing may be reduced, resulting in lower levels of AZT-monophosphate associated with toxicity and maintaining levels of AZT-triphosphate associated with efficacy.