title: High rate of complete viral suppression with combination therapy in patients with chronic hepatitis B and prior treatment failure.
abstract: BACKGROUND
  Combination therapy for chronic hepatitis B virus (HBV) infection is recommended for patients with antiviral resistance (AVR) or partial response (PR) to earlier antiviral therapy; however, data on outcomes are limited.
  
  
  OBJECTIVE
  To determine the rate of complete viral suppression (CVS) with combination therapy and to compare CVS among different indications and treatment regimens.
  
  
  METHODS
  A cohort of 109 consecutive patients with chronic hepatitis B from 3 liver clinics in Northern California was retrospectively studied. All patients started combination therapy between April 2004 and August 2009 for the following indications: AVR (n = 29), PR (n = 60), or others (n = 20). Combination treatments included lamivudine (LAM), adefovir (ADV), telbivudine (LdT), entecavir (ETV), tenofovir (TDF), and emtricitabine (FTC). CVS was defined as undetectable serum HBV DNA <100 IU/mL.
  
  
  RESULTS
  Among the patients, who were nearly all Asian (99%), 73% had ≥ 2 prior treatments and 82% had treatment failure (AVR or PR). Median treatment duration of combination therapy was 21 months (range, 6 to 50 mo). The majority (77%) achieved CVS after 6 months of various combination regimens: 80% for ETV+TDF, 76% for TDF+LAM or FTC or LdT, 75% for ETV+ADV, and 69% for ADV+LAM or LdT (P = 0.86). After 6 months of therapy, CVS was observed in a similar proportion of patients treated for PR and AVR (72% and 74%, respectively).
  
  
  CONCLUSIONS
  Although the majority of 109 treatment-experienced patients had prior treatment failure, high rates of CVS were rapidly achieved and did not significantly differ between indications of AVR and PR or between ETV-based and TDF-based regimens.
authors.affiliation: Pacific Health Foundation, Department of Medicine, Stanford University Medical Center, Stanford, CA, USA.
authors.forename: Carrie R
authors.initials: CR
authors.lastname: Wong
authors.forename: Huy N
authors.initials: HN
authors.lastname: Trinh
authors.forename: Benjamin
authors.initials: B
authors.lastname: Yip
authors.forename: Huy A
authors.initials: HA
authors.lastname: Nguyen
authors.forename: Ruel T
authors.initials: RT
authors.lastname: Garcia
authors.forename: Aijaz
authors.initials: A
authors.lastname: Ahmed
authors.forename: Emmet B
authors.initials: EB
authors.lastname: Keeffe
authors.forename: Mindie H
authors.initials: MH
authors.lastname: Nguyen
mesh_terms: D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D044466:Asian People; D002140:California; D015331:Cohort Studies; D004279:DNA, Viral / Q000097:blood; D024882:Drug Resistance, Viral; D004359:Drug Therapy, Combination; D005260:Female; D006515:Hepatitis B virus / Q000187:drug effects*; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors; D017211:Treatment Failure
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral