Severe Kidney Dysfunction Is Uncommon in HIV Patients Treated with Tenofovir (Viread) plus Boosted Atazanavir (Reyataz)

Kidney (renal) toxicity (nephrotoxicity) is a potential adverse side effect of antiretroviral therapy. Some studies have shown an association between kidney toxicity and use of tenofovir disoproxil fumarate (Viread), but data have been inconsistent.

The authors of the present study, reported in the current issue of Antiviral Therapy, had 2 objectives:

The investigators conducted a prospective 48-week open-label trial that evaluated the safety of tenofovir used with ritonavir-boosted atazanavir (Reyataz) and optimized nucleoside reverse transcriptase inhibitors (NRTIs) in patients with documented prior treatment failure.

The study included 53 participants with a median CD4 cell count of 206 cells/mm3 and a median HIV RNA level of 5 log10 copies/mL. At baseline, all patients had normal serum creatinine levels and creatinine clearance (markers of renal dysfunction), which were stable within the 2 months preceding study inclusion.

Two patients discontinued tenofovir due to severe renal impairment and 2 never started tenofovir, leaving 49 subjects without clinical nephrotoxicity to be analyzed. Statistical analysis was performed on an intent-to-treat basis.

Results

Conclusion

According to the study authors, "This study confirms that tenofovir-related severe nephrotoxicity is an uncommon event."

"In patients without clinical nephrotoxicity, the use of tenofovir during a 1-year period was associated with a slight but significant alteration of renal function, which was not associated with increased trough concentration," they added.

INSERM SC10, Villejuif, France.


12/07/07

Reference
L Gérard L, C Chazallon, AM Taburet, and others. Renal function in antiretroviral-experienced patients treated with tenofovir disoproxil fumarate associated with atazanavir/ritonavir. Antiviral Therapy 12(1): 31-39. 2007.