P372. Prospective, randomized clinical trial comparing the efficacy of two vaccines against hepatitis B virus (HBV) in inflammatory bowel disease (IBD) patients
M. Chaparro1, J. Gordillo2, E. Domènech3, M. Esteve4, M. Barreiro-de Acosta5, A. Villoria6, E. Iglesias-Flores7, P. Huelín8, J. Naves3, O. Benítez4, L. Nieto5, X. Calvet6, V. García-Sánchez7, J. Villagrasa9, A.C. Marín10, M. Ramas1, I. Moreno11, J. Maté1, J.P. Gisbert1, 1Hospital Universitario de La Princesa, IP and CIBERehd, Gastroenterology Unit, Madrid, Spain, 2Hospital Santa Creu i Sant Pau, Gastroenterology Unit, Barcelona, Spain, 3Hospital Universitari Germans Trias i Pujol and CIBERehd, Gastroenterology Unit, Barcelona, Spain, 4Hospital Universitario Mutua de Terrassa and CIBERehd, Gastroenterology Unit, Terrasa, Spain, 5Complejo Hospitalario Universitario de Santiago, Gastroenterology Unit, Santiago de Compostela, Spain, 6Hospital de Sabadell and CIBERehd, Gastroenterology Unit, Sabadell, Spain, 7Hospital Universitario Reina Sofía, Gastroenterology Unit, Córdoba, Spain, 8Hospital de la Santa Creu i Sant Pau, Gastroenterology Unit, Barcelona, Spain, 9Hospital Universitario de La Princesa and IP, Preventive Medicine Unit., Madrid, Spain, 10Hospital Universitari Germans Trias i Pujol and CIBERehd, Gastroenterology Unit, Madrid, Spain, 11Hospital Universitario de La Princesa and IP, Fundación de Investigación Biomédica, Madrid, Spain
Around 50% of IBD patients do not respond to the HBV vaccine (vs. 5% of healthy controls). To increase the success rate, different vaccination protocols have been proposed although no study has been able to establish the optimal strategy for IBD patients.
Aims: To compare the success rate between two HBV vaccines in IBD patients: traditional (Engerix ®) and a new vaccine with adjuvant (Fendrix ®). Secondary aim was to identify predictor factors of response to the vaccine.
IBD patients with negative HBV serology and without previous vaccination against HBV were included and randomized 1:1 to receive Fendrix® or double doses of Engerix® at months 0, 1, 2 and 6. Anti-HBs concentration was measured 2 months after the 3rd and 4th doses (at months 4 and 8). (EUDRA CT number: 2010-023947–14).
170 patients had been included: 55% male, 52% with Crohn's disease, 30% under immunosuppressants and 37% under anti-TNF treatment. 54% of patients received Engerix ® and 46% Fendrix®; the main characteristics of patients (age, gender, type of IBD and treatment) were similar between the 2 groups. Overall, 44% of patients had response (anti-HBs ≥100 IU/l) after the first 3 doses (161 patients have already received 3 doses), and 71% after the completion of the vaccination (134 have completed the vaccination). The response rate after the 4 doses was 67% with Engerix® vs. 76% with Fendrix® (p = 0.2); considering anti-HBs ≥10 IU/l (the standard threshold to consider response), the response rate was higher with Fendrix® than with Engerix® (87 vs. 73.6%, p = 0.04). In patients under immunosuppressants or anti-TNF drugs, the response (anti-HBs ≥100 IU/l) after the 4 doses was 55% with Engerix® vs. 69% with Fendrix® (p = 0.12). In the multivariate analysis, older age (odds ratio [OR] = 0.9, p < 0.0001) and immunosuppressants or anti-TNF concomitant treatment (OR = 0.04, p < 0.0001), but not the type of vaccine (OR = 1.9, p = 0.1), were associated with the response rate to the vaccination. 7.7% of patients flared up during the study period, and 13% suffered adverse events (only 41% related with the vaccine, and all of them mild). The frequencies of flaring up and adverse events were similar between the 2 groups.
A statistically significant different response rate to Fendrix® (single dose) or Engerix® (double dose) has not been demonstrated in IBD patients yet (although the trial is still ongoing). A 4-dose schedule increases the response rate around 30% compared with a 3-dose regimen. The older age and the immunosuppressive and anti-TNF treatment decrease the success rate of the vaccine. Both vaccines seem to be safe in IBD patients.