Maternal Antiviral Prophylaxis to Prevent Perinatal Transmission of Hepatitis B Virus in Thailand
Condition: Hepatitis B Chronic Infection; Pregnancy
MeSH terms: Hepatitis A; Hepatitis B; Persistent Infection; Hepatitis B, Chronic; Hepatitis
Intervention: tenofovir disoproxil fumarate; placebo
Intervention description: administration: tablet 300 mg, once a day, from enrollment at 28 weeks' gestation until 2 months postpartum; administration: one tablet, once a day, from enrollment at 28 weeks' gestation until 2 months postpartum
Intervention MeSH terms: Tenofovir
Phase: Phase 3
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Enrollment: 654.0
Sex: Female
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Hepatitis B; Hepatitis B sAg; Hepatitis B eAg; pregnancy

Summary:

      Chronic hepatitis B (CHB) infection is complicated by cirrhosis and liver cancer. In
      Thailand, 7% of adults are chronically infected by Hepatitis B virus (HBV). The risk of
      perinatal transmission of HBV is about 12% when a mother has a high HBV load in her plasma,
      even if her infant receive specific immunoglobulin and vaccine.

      The hypothesis of this study is that a potent antiviral, tenofovir, can decrease HBV load in
      HBV infected pregnant women and therefore reduce the risk of perinatal transmission/ Pregnant
      women participating in this study will receive tenofovir or placebo during the last trimester
      of pregnancy and two months postpartum. The risk of perinatal transmission will be compared
      between the two groups.

      The results of the study will help define policy to manage HBV infected pregnant women to
      prevent perinatal transmission.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Pregnancy

          -  At least 18 years of age

          -  Negative Human Immunodeficiency Virus (HIV) serology

          -  Positive HBsAg and hepatitis B e antigen (HBeAg) tests

          -  Gestational age of 28 weeks (+ or - 10 days) as determined by obstetrician

          -  Alanine Aminotransferase (ALT)≤30 U/L, confirmed ≤60 U/L on a subsequent blood draw

          -  Agreeing to bring their infants at the planned study visits at one study site until
             one year after delivery and to inform the site investigators if they plan to move to
             another place and not be able to return to the clinic.

          -  Understanding the need for adequate infant immunization and agreeing to the blood
             draws from their infants and the need for close follow up to manage possible
             exacerbation of hepatitis.

        Exclusion Criteria:

          -  History of tenofovir treatment at any time, or any other anti-HBV treatment during the
             current pregnancy

          -  Creatinine clearance <50 ml/min, calculated using the Cockcroft-Gault formula

          -  Dipstick proteinuria>1+ (>30 mg/dL) or normoglycemic glucosuria confirmed on two
             separate occasions

          -  Positive serology for Hepatitis C infection less than 12 months prior to enrollment

          -  Evidence of pre-existing fetal anomalies incompatible with life

          -  Any concomitant condition or treatment that, in the view of the clinical site
             investigator, would contraindicate participation or satisfactory follow up in the
             study.

          -  Concurrent participation in any other clinical trial without written agreement of the
             two study teams