Flu vaccine protective in IBD, less so with TNF-blockers

Last Updated: 2015-09-24

By Reuters Staff

NEW YORK (Reuters Health) - The flu vaccine yields high seroprotection rates in patients with inflammatory bowel disease (IBD), but protection is less persistent in those taking anti-tumor necrosis factor (anti-TNF) drugs.

Data on the efficacy and safety of seasonal influenza vaccines in patients IBD "remain scarce," the authors note.

Dr. Odile Launay, of the Paris Descartes University in France, and colleagues evaluated the impact of immunosuppressive (IS) therapeutics on serological responses to two years of flu vaccines in adults with ulcerative colitis or Crohn's disease.

Participants were divided into three groups: no IS therapy, IS without treatment with anti-TNF, and treatment with anti-TNF with or without IS therapy.

In the first vaccination season - September to December 2009 - there were 31 patients in the no IS treatment group, 77 in the IS without anti-TNF group, and 117 in the anti-TNF with or without IS treatment. The following year, there were 33, 49, and 81 patients in the three groups, respectively.

Participants received the trivalent inactivated influenza vaccine for the three strains recommended by the World Health Organization (WHO) for the 2009-2010 and 2010-2011 flu seasons. Fifty-two patients also opted to receive the 2009 pandemic A/H1N1 vaccine at least four weeks after the trivalent vaccine.

Hemagglutination inhibition (HI) titers were assessed before vaccination, and three weeks and six months after vaccination.

As reported online September 8 in the Journal of Crohn's and Colitis, baseline seroprotection rates were not significantly different between groups.

Seroprotection rates three weeks after vaccination were 77% (no IS treatment), 75% (IS without anti-TNF), and 66% (anti-TNF with or without IS) for A/H1N12007.

For A/H3N2, rates of seroprotection were 77%, 68%, and 52%, respectively, and for the B-strain, they were 97%, 96%, and 95%, respectively, at three weeks.

Over time, however, seroprotection rates for both A/H1N12007 and A/H3N2 became significantly lower in patients on TNF-blockers. At six months, for example, seroprotection rates for A/H3N2 were 52%, 45%, and 17%, respectively (p<0.0001) and at 12 months they were 46%, 40%, and 13% (p<0.0001).

The results for the second year were comparable to the first year.

At least one vaccine-related event was reported in 10%, 19%, and 12% of patients.

"In conclusion," the authors wrote, "in adult patients with IBD, the trivalent influenza vaccines yielded high seroprotection rates with however lower seroprotection against H3N2 and H1N1 strains than against B strain and more rapid decline in patients receiving anti-TNF with or without IS."

They added, "These results support the recommendations for vaccination of patients with IBD, but more immunogenic vaccines for patients receiving anti-TNF are needed."

Dr. Launay did not respond to a request for comment.

SOURCE: http://bit.ly/1QU6GsB

J Crohn's Colitis 2015.