001). Treatment response was not affected by prior HBV treatment. Furthermore, no resistance Crizotinib to tenofovir DF developed through

week 72. Among patients with an alanine aminotransferase (ALT) greater than the upper limit of normal at baseline, normalization of ALT occurred in 74% of patients receiving tenofovir DF and 31% of patients receiving placebo (P < 0.001). The rate of grade 3/4 adverse events was higher among patients treated with placebo (24%) than patients treated with tenofovir DF (10%). No patients met the safety endpoint of a 6% decrease in spine bone mineral density at week 72. The authors concluded that tenofovir DF therapy in HBV-infected adolescents was well tolerated and highly effective at suppressing HBV DNA and normalizing ALT values in both treatment-naïve adolescents and those with prior exposure to HBV therapy. There are several potential limitations of this study. Most of the subjects enrolled in this study were Caucasian patients from Poland and had HBV genotypes A and D. In the

United States, genotypes A and C are most common, so whether these results translate into similar findings in adolescents with genotype click here C is currently unknown.2 Tenofovir DF has been associated with decreased bone density and osteoporotic fracture risk in human immunodeficiency virus–positive patients.3 Over 72 weeks of therapy, no significant decrease in spine bone mineral density was observed, but whether this observation will persist in adolescents with chronic HBV after a longer period of use of tenofovir DF is not known. ALT, alanine aminotransferase; DF, disoproxil fumarate;

HBV, hepatitis B virus. It is quite gratifying to witness the continued pipeline of pharmaceuticals to combat HBV infection being studied and ultimately receiving approval for use in children and adolescents. It was not that long ago that there were no approved medications medchemexpress or very few limited drugs to treat HBV. Although universal use of HBV vaccine will ultimately prove to be the single greatest public health measure to combat chronic HBV infection, for those unfortunate children and adolescents afflicted with the disease, medications such as tenofovir DF hold the promise of allowing long and healthy lives. Although this study was limited to adolescents, future study of tenofovir DF in younger children is being initiated.