In an article in the December 2006 issue of the European Journal of Gastroenterology and Hepatology, the authors describe the effect of switching to tenofovir with emtricitabine in seven patients failing to respond to an adefovir-containing regimen.

The authors conclude that:

"In patients failing to respond to adefovir monotherapy or an adefovir-containing regimen for chronic hepatitis B virus, a combination of tenofovir and emtricitabine resulted in undetectable hepatitis B viral DNA levels without any renal toxicity. Tenofovir, in combination with emtricitabine, may be an alternative treatment for those with detectable hepatitis B viral DNA on adefovir".