What is the recommended dosing regimen for Engerix-B (hepatitis B vaccine)?

Engerix-B Dosing Recommendations

Standard Adult Dosing (≥20 years)

For adults aged 20 years and older, administer Engerix-B 20 μg (1.0 mL) intramuscularly at 0,1, and 6 months. 1, 2

• This 3-dose schedule achieves >90% seroprotection rates in adults under 40 years of age 1
• The vaccine should be administered in the deltoid muscle 2
• Shake the vial well before administration; the vaccine should appear as a slightly turbid white suspension 2

Adolescent Dosing (11-19 years)

Adolescents aged 11-19 years should receive Engerix-B 10 μg (0.5 mL) at 0,1, and 6 months. 1, 2

• An alternative 2-dose regimen using the adult formulation (20 μg) at 0 and 6 months is also acceptable for adolescents aged 11-15 years 1, 3
• The 2-dose regimen achieves 96.7% seroprotection, which is non-inferior to the standard 3-dose schedule 3

Pediatric Dosing (Birth through 10 years)

Children from birth through age 10 should receive Engerix-B 10 μg (0.5 mL) at 0,1, and 6 months. 1, 2

• For infants born to HBsAg-positive mothers, the first dose must be given within 12 hours of birth along with HBIG 4, 2
• The final dose must not be administered before 24 weeks of age 4

Hemodialysis and Immunocompromised Patients (≥20 years)

Adults on hemodialysis or who are immunocompromised require Engerix-B 40 μg (2.0 mL) administered as either a single 2-mL injection or two 1-mL injections at 0,1,2, and 6 months (4-dose series). 1, 2

• Annual anti-HBs testing is mandatory for hemodialysis patients 2
• Administer a 40 μg booster dose when antibody levels fall below 10 mIU/mL 2
• Do not use Heplisav-B or PreHevbrio in hemodialysis patients, as safety and efficacy have not been established 1

Alternative Accelerated Schedules

For rapid protection in high-risk situations (recent exposure, travelers), use the accelerated 4-dose schedule: 0,1,2, and 12 months. 1, 2

• This schedule is designed for neonates born to HBV-infected mothers, recently exposed individuals, and certain travelers to high-risk areas 2
• The additional dose at 12 months is recommended for prolonged maintenance of protective titers 2

Critical Minimum Intervals

If the vaccination series is interrupted, do not restart—simply continue where you left off. 1, 4

• Minimum interval between doses 1 and 2: 4 weeks 1
• Minimum interval between doses 2 and 3: 8 weeks 1
• Minimum interval between doses 1 and 3: 16 weeks 1
• Doses administered ≤4 days before the minimum interval are considered valid 1, 4

Special Population Considerations

Pregnant Women

Pregnant women requiring hepatitis B vaccination should receive Engerix-B, Recombivax HB, or Twinrix only. 1

• Do not use Heplisav-B or PreHevbrio in pregnancy due to insufficient safety data 1

Older Adults

Vaccine response declines with age; adults over 40 years have lower seroconversion rates than younger adults. 1

• Consider post-vaccination serologic testing 1-2 months after series completion in older adults to document response 5
• For documented non-responders, consider revaccination with Heplisav-B (90% seroprotection) or a high-dose Engerix-B series (40 μg at 0,1,2, and 6 months) 5

Common Pitfalls to Avoid

• Never restart the series if interrupted—this wastes doses and delays protection 1, 4
• Never administer the third dose before 16 weeks from the first dose, even if 8 weeks have passed since the second dose 1
• Never use standard adult doses (20 μg) in hemodialysis patients—they require 40 μg doses 1, 2
• Never administer subcutaneously unless the patient has a bleeding disorder—this results in lower antibody titers and increased local reactions 2
• Never use Heplisav-B or PreHevbrio in pregnant women, children, or hemodialysis patients 1