A Cochrane review [Abstract] 2 included 13 studies with a total of 567 476 subjects randomised to pre- or post-exposure prophylaxis. Immunoglobulins, when used for pre-exposure prophylaxis, reduced the number of adult patients with hepatitis A at 6 to 12 months (RR 0.53, 95% CI 0.40 to 0.70; 6 studies) in comparison with no intervention or inactive control. Similar effect was seen in children aged 3 to 17 at 6 to 12 months follow-up (RR 0.45, 95% CI 0.34 to 0.59; 4 studies). No significant systemic adverse events were reported. One study showed that immunoglobulin was more effective than placebo for post-exposure prophylaxis. There was no significant difference between immunoglobulins and inactivated hepatitis A vaccine in seroconversion to hepatitis A vaccine antibodies at 4 weeks (RR 1.16, 95% CI 0.98 to 1.38), but immunoglobulins were significantly less effective than vaccine in maintaining hepatitis A antibody seropositivity at 8, 12, or 24 weeks.
A systematic review 1 including 6 studies classified as RCTs with a total of 279,944 subjects was abstracted in DARE. IGs were more effective than placebo or no treatment in the primary prevention of infectious hepatitis and hepatitis A across all ages; 4 RCTs suggested an effectiveness of 83% (Random-effects RR 0.17, 95% CI: 0.06, 0.51, P=0.001). There was significant statistical heterogeneity among the studies (P<0.00001), although the studies showed the same direction of effect. The effectiveness of IG was lower in adults (52%) than in children (90%). IGs were more effective than placebo or no treatment in the prevention of infectious hepatitis and hepatitis A after exposure across all ages; 2 RCTs suggested an effectiveness of 69% (RR 0.31, 95% CI: 0.20 to 0.47).
Comment: The quality of evidence is downgraded by serious limitations in study quality (inadequate or unclear allocation concealment) and by inconsistency (heterogeneity in interventions and outcomes and variability in results across studies).
Primary/Secondary Keywords