Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement

Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.


Immunogenicity and Short Term Safety of Pandemic Influenza Vaccine (Anti-H1n1) in Patients with Juvenile Idiopathic Arthritis.

Aikawa3,  Nadia E., Campos5,  Lucia M. A., Silva5,  Clovis A., Guissa5,  Vanessa R., Sallum5,  Adriana M., Jesus5,  Adriana A., Moraes4,  Julio B.

Adolpho Lutz Institute, University of Sao Paulo
Butantan Institute
Division of Rheumatology, Pediatric Reumatology Unit, Universidade de Sao Paulo
Division of Rheumatology, Universidade de Sao Paulo
Pediatric Reumatology Unit, Universidade de Sao Paulo

Purpose:

To assess immunogenicity and safety of pandemic influenza vaccine (anti-H1N1) in patients with juvenile idiopathic arthritis (JIA).

Methods:

60 JIA patients and 55 age-matched healthy controls were vaccinated with cepa A/California/7/2009 (NYMC X-179A) anti-H1N1 vaccine. All participants received 1 dose of immunization, and those <9yrs of age received a second dose 3 weeks apart. All subjects were evaluated before and 3 weeks after complete vaccination. Serology against H1N1 virus was performed by hemagglutination inhibition (HI) antibody (Ab) assay. Appropriate endpoints included the percentage of subjects achieving HI Ab titer >=1:40 (seroprotection) and rates of seroconversion, defined as the percentage of subjects with either a pre-vaccination HI titer <1:10 and a post vaccination HI titer >1:40 or a pre-vaccination HI titer >1:10 and a minimum 4-fold rise in post-vaccination HI Ab titer. Demographic data, JIA onset subtype, disease duration, activity status, patient VAS and CHAQ score were analyzed. Post-vaccination adverse events (AEs) were searched. Fisher's exact and Mann Whitney tests were used for statistical analysis considering p<0.05 significant.

Results:

Mean age of JIA patients and controls was 13.5±5.3yrs and 12.3±2.6yrs, (p=0.08); median JIA disease duration was 6.7±5.3yrs.

JIA subtypes were 48% polyarticular, 27% oligoarticular, 13% systemic and 12% others. Thirty seven patients (62%) were taking at least one DMARD and 17 (28%) were under biologic therapy (22% anti-TNF; 7% abatacept). Patient VAS, CHAQ score, ESR and CRP levels remained unchanged after immunization (p>0.05). Seroprotection rates against H1N1 influenza virus increased from 23 to 83% in JIA and from 22 to 95% in controls (p=0.08). Seroconversion rates were achieved in 78% JIA and 89% controls (p=0.14). Following vaccination, mean HI Ab titers ranged from 39±103 to 495±634 for patients and from 24±44 to 457±497 for controls (p=0.44). Seroprotection, seroconversion and mean HI Ab titers were not associated to use of DMARDs and/or biologic agents by JIA patients, although, mean HI Ab titer was significantly lower in patients <9yrs of age compared to those between 9–18yrs (217±354 vs. 628±723, p=0.016); notably, frequencies of MTX and DMARDs use were higher in the former group (71% vs. 35%, p=0.03 and 86% vs. 46%, p=0.01, respectively). AEs were reported by 40% patients and 42% controls with rates of 2.4 AE/JIA patient and 1.6 AE/control. Most frequent AEs in patients and controls were local pain (23% vs. 29%, p=0.53), headache (18% vs. 18%, p=1.0), malaise (15% vs. 7%, p=0.24), myalgia (13% vs. 7%, p=0.37), arthralgia (13% vs. 2%, p=0.07) and fever (5% vs 3.6%, p=1.0).

Conclusion:

Vaccination of JIA patients against pandemic influenza A (H1N1) generated successful protective antibody production with short term safety profile.

To cite this abstract, please use the following information:
Aikawa, Nadia E., Campos, Lucia M. A., Silva, Clovis A., Guissa, Vanessa R., Sallum, Adriana M., Jesus, Adriana A., et al; Immunogenicity and Short Term Safety of Pandemic Influenza Vaccine (Anti-H1n1) in Patients with Juvenile Idiopathic Arthritis. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :224
DOI: 10.1002/art.27993

Abstract Supplement

Meeting Menu

2010 ACR/ARHP