Switching From TDF to TAF vs. Maintaining TDF in Chronic Hepatitis B With Resistance to Adefovir or Entecavir.

Summary

Treatment of CHB patients with genotypic resistance to NUCs has been problematic due to the lack of data from randomized trials. Recently, two randomized trials comparing the efficacy of TDF monotherapy versus TDF and ETV combination therapy in CHB patients with documented genotypic resistance to adefovir (ADV) or ETV demonstrated TDF monotherapy was not statistically different in viral suppression at week 48 of treatment.1,2 The extension study based on the above two trials merged study subjects from these trials with changing from TDF and ETV combination group to TDF monotherapy to evaluate long-term efficacy and safety of TDF monotherapy for multidrug-resistant patients. At the time of merging of 192 subjects, by intention-to-treat analysis, 66.3% of TDF group and 68.0% of TDF-ETV group had virological response as determined by serum HBV DNA \<15 IU/mL. (in press) Three year long-term follow up study showed that the proportion of virologic suppression increased to 76.8% and 72.2% in TDF-TDF and TDF/TDF-ETV groups, respectively( P=0.46). (in press) TAF, a novel prodrug of tenofovir was developed to have greater stability in plasma than TDF, thereby enabling more efficient delivery of the active metabolite to target cells at a substantially lower dose. The reduced systemic exposure of tenofovir offers the potential for an improved safety profile compared to TDF a benefit that demonstrated in a recent clinical trial in patients with HIV infection. In a recent double-blind randomized phase 3 noninferiority trial with 873 treatment naive patients who were positive for HBeAg, the proportion of patients receiving TAF who had HBV DNA \<29 IU/mL at week 48 was 64%, which was non-inferior to the rate of 67% in patients receiving TDF (P=0.25).3 In the safety profile, TAF group had significantly smaller decrease in BMD than TDF group in the hip and spine, as well as significantly smaller increases in serum creatinine at week 48.3 For treatment naive HBeAg negative patients, a recent study with 425 subjects applied the same methodology and showed noninferiority in efficacy of TAF compared to TDF at week 48.4 Considering noninferiority in efficacy and superior bone and renal safety from TAF, TAF might be considered preferred choice of NUC instead of TDF. However, it is still unknown whether TAF would show similar efficacy and safety profile in patients with multidrug-resistant CHB.

Timeline

Start

2017-10-26

Primary completion

2021-03-25

Completion

2021-03-25

Publications

• Results Chae HB, Kim JH, Kim JK, Yim HJ. Current status of liver diseases in Korea: hepatitis B. Korean J Hepatol. 2009 Dec;15 Suppl 6:S13-24. doi: 10.3350/kjhep.2009.15.S6.S13.
• Results Kim SR, Kudo M, Hino O, Han KH, Chung YH, Lee HS; Organizing Committee of Japan-Korea Liver Symposium. Epidemiology of hepatocellular carcinoma in Japan and Korea. A review. Oncology. 2008;75 Suppl 1:13-6. doi: 10.1159/000173419. Epub 2008 Dec 17.
• Results Liaw YF, Sung JJ, Chow WC, Farrell G, Lee CZ, Yuen H, Tanwandee T, Tao QM, Shue K, Keene ON, Dixon JS, Gray DF, Sabbat J; Cirrhosis Asian Lamivudine Multicentre Study Group. Lamivudine for patients with chronic hepatitis B and advanced liver disease. N Engl J Med. 2004 Oct 7;351(15):1521-31. doi: 10.1056/NEJMoa033364.
• Results Chen CJ, Yang HI, Su J, Jen CL, You SL, Lu SN, Huang GT, Iloeje UH; REVEAL-HBV Study Group. Risk of hepatocellular carcinoma across a biological gradient of serum hepatitis B virus DNA level. JAMA. 2006 Jan 4;295(1):65-73. doi: 10.1001/jama.295.1.65.
• Results Iloeje UH, Yang HI, Su J, Jen CL, You SL, Chen CJ; Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer-In HBV (the REVEAL-HBV) Study Group. Predicting cirrhosis risk based on the level of circulating hepatitis B viral load. Gastroenterology. 2006 Mar;130(3):678-86. doi: 10.1053/j.gastro.2005.11.016.
• Results Chang TT, Lai CL, Kew Yoon S, Lee SS, Coelho HS, Carrilho FJ, Poordad F, Halota W, Horsmans Y, Tsai N, Zhang H, Tenney DJ, Tamez R, Iloeje U. Entecavir treatment for up to 5 years in patients with hepatitis B e antigen-positive chronic hepatitis B. Hepatology. 2010 Feb;51(2):422-30. doi: 10.1002/hep.23327.
• Results Snow-Lampart A, Chappell B, Curtis M, Zhu Y, Myrick F, Schawalder J, Kitrinos K, Svarovskaia ES, Miller MD, Sorbel J, Heathcote J, Marcellin P, Borroto-Esoda K. No resistance to tenofovir disoproxil fumarate detected after up to 144 weeks of therapy in patients monoinfected with chronic hepatitis B virus. Hepatology. 2011 Mar;53(3):763-73. doi: 10.1002/hep.24078. Epub 2010 Dec 22.
• Results Zoulim F, Durantel D, Deny P. Management and prevention of drug resistance in chronic hepatitis B. Liver Int. 2009 Jan;29 Suppl 1:108-15. doi: 10.1111/j.1478-3231.2008.01939.x.
• Results Bartholomeusz A, Locarnini SA. Antiviral drug resistance: clinical consequences and molecular aspects. Semin Liver Dis. 2006 May;26(2):162-70. doi: 10.1055/s-2006-939758.
• Results Lim YS, Yoo BC, Byun KS, Kwon SY, Kim YJ, An J, Lee HC, Lee YS. Tenofovir monotherapy versus tenofovir and entecavir combination therapy in adefovir-resistant chronic hepatitis B patients with multiple drug failure: results of a randomised trial. Gut. 2016 Jun;65(6):1042-51. doi: 10.1136/gutjnl-2014-308435. Epub 2015 Mar 23.
• Results Lim YS, Byun KS, Yoo BC, Kwon SY, Kim YJ, An J, Lee HC, Lee YS. Tenofovir monotherapy versus tenofovir and entecavir combination therapy in patients with entecavir-resistant chronic hepatitis B with multiple drug failure: results of a randomised trial. Gut. 2016 May;65(5):852-60. doi: 10.1136/gutjnl-2014-308353. Epub 2015 Jan 16.
• Results Chan HL, Fung S, Seto WK, Chuang WL, Chen CY, Kim HJ, Hui AJ, Janssen HL, Chowdhury A, Tsang TY, Mehta R, Gane E, Flaherty JF, Massetto B, Gaggar A, Kitrinos KM, Lin L, Subramanian GM, McHutchison JG, Lim YS, Acharya SK, Agarwal K; GS-US-320-0110 Investigators. Tenofovir alafenamide versus tenofovir disoproxil fumarate for the treatment of HBeAg-positive chronic hepatitis B virus infection: a randomised, double-blind, phase 3, non-inferiority trial. Lancet Gastroenterol Hepatol. 2016 Nov;1(3):185-195. doi: 10.1016/S2468-1253(16)30024-3. Epub 2016 Sep 22.
• Results Buti M, Gane E, Seto WK, Chan HL, Chuang WL, Stepanova T, Hui AJ, Lim YS, Mehta R, Janssen HL, Acharya SK, Flaherty JF, Massetto B, Cathcart AL, Kim K, Gaggar A, Subramanian GM, McHutchison JG, Pan CQ, Brunetto M, Izumi N, Marcellin P; GS-US-320-0108 Investigators. Tenofovir alafenamide versus tenofovir disoproxil fumarate for the treatment of patients with HBeAg-negative chronic hepatitis B virus infection: a randomised, double-blind, phase 3, non-inferiority trial. Lancet Gastroenterol Hepatol. 2016 Nov;1(3):196-206. doi: 10.1016/S2468-1253(16)30107-8. Epub 2016 Sep 22.
• Byun KS, Choi J, Kim JH, Lee YS, Lee HC, Kim YJ, Yoo BC, Kwon SY, Gwak GY, Lim YS. Tenofovir Alafenamide for Drug-Resistant Hepatitis B: A Randomized Trial for Switching From Tenofovir Disoproxil Fumarate. Clin Gastroenterol Hepatol. 2022 Feb;20(2):427-437.e5. doi: 10.1016/j.cgh.2021.04.045. Epub 2021 May 4.

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