Tenofovir, tenvir antiviral treatment of hepatitis B most effective drug
The current nucleoside analogues for the treatment of chronic hepatitis B include lamivudine (LAM), adefovir (ADV), telbivudine (LdT), entecavir (ETV) and tenofovir (TDF). The first four drugs have been listed in the domestic market and have been widely used clinically, while TDF is only listed in foreign countries, the country has not been used to treat hepatitis B. Therefore, this article will be the characteristics of the drug, clinical efficacy, drug resistance and other brief introduction.
First, TDF PK / PD basic features
TDF is administered as its prodrug tenofovir disoproxil fumarate [9- (R) -2- (phosphooxy) -propyl] adenine, or PMPA) and is phosphorylated to PMPApp Of nucleotides. PMPApp, when incorporated into DNA strands, terminates the DNA strand and is a competitive inhibitor of native deoxyadenosine 5'-triphosphate. After oral administration, Tenofovir disoproxil fumarate is converted to Tenofovir by plasma esterase. Tenofovir is cleared by glomerular filtration and active secretion by the renal tubules. A dose-range study in patients with HIV-1 infection showed that a TDF dose of 300 m was optimal and no dose-range studies were performed in HBV-infected patients. In patients with HBV, the recommended dose of TDF is 300 mg / day, regardless of whether the nucleoside analogue was given.
The company is located in:
Second, tenofovir clinical efficacy
Phase III clinical studies 102 and 103 compared the efficacy of TDF and ADV in HBeAg-negative and HBeAg-positive patients, respectively [1-2]. At 48 weeks, patients in the ADV group were treated with TDF for further treatment. The results of the study (see Table 1 for details) showed that at 48 weeks, the negative rate of HBV DNA in TDF group was significantly higher than that in ADV group (93% and 63%, respectively; P <0.001 for HBeAg-negative patients; 76 % And 13%, P <0.001). HBeAg seroconversion rates were similar between the two groups (21% and 18%, respectively, P = 0.36), and HBsAg negative rates were higher in the two groups than in the ADV group (3.2% and 0, respectively; P = 0.02). At week 144, HBV DNA was <400 copies / mL in 87% of HBeAg-negative patients and 72% of HBeAg-positive patients in the TDF group and 88% and 71% in the ADV-converted TDF group, respectively Respectively, 81% and 74%, sustained normal ALT levels, HBeAg negative rate of 34%. Visible ADV treatment group converted to TDF, more patients received HBV DNA negative, negative rate and TDF naive patients similar.
The company is located in:
TDF is a novel nucleoside (acid) analog, and clinical studies have shown that it has a good antiviral effect against HBV, HIV infection and lamivudine-resistant patients . The latest research also shows that, TDF alone treatment of CHB single infection also has a good effect and virus inhibition. Because TDF is superior to adefovir dipivoxil against HBV, the incidence of drug resistance is low and is effective in most HBV resistant strains. Therefore, TDF has broad application prospects in the treatment of HBV infection . Many clinical studies on the efficacy and safety of TDF in the treatment of single CHB are in full swing. However, TDF has been widely used in the treatment of hepatic insufficiency, renal insufficiency, The efficacy and safety of transplantation and other patients still need further large-scale clinical studies confirmed that the efficacy and safety of CHB in pregnant women and children also need further study. I believe that through the continuous collaborative efforts of scholars from various countries, the old drugs will be continuously improved and popularized. New and better CHB drugs will also emerge in an endless stream, bringing good news to relieve the suffering of the vast majority of patients.