Crohn's disease patients who smoke or use narcotics appear to be less likely to respond to treatment with biologic agents, researchers suggested here.
In a retrospective study among 44 patients who were not responding to infliximab (Remicade), about 66% of those patients did not respond to subsequent treatment with adalimumab (Humira), said Ira Shafran, MD, medical director of the Shafran Gastroenterology Center Winter Park, Fla
When Shafran analyzed possible reasons for nonresponse, he noted that 45% of the nonresponding patients were smokers, while only 7% of responders were current smokers.
In addition, 55% of nonresponders were also taking narcotics, compared with 13% of the responders, Shafran told MedPage Today at his poster presentation during the annual meeting of the American College of Gastroenterology.
"I think we should advise our patients with Crohn's disease to stop smoking and to stop using narcotics if they are going to use biologic agents for this disease," Shafran said.
He said that nonresponders to infliximab therapy were more likely not to respond to subsequent treatment with adalimumab. Of the 44 patients in the study who did not respond to infliximab, 29 also did not respond to adalimumab.
"Infliximab is an effective therapy for Crohn's disease," Shafran explained, "but its chimeric nature may induce human antichimeric antibody responses, resulting in infusion reactions, elevated immune responses, and loss of efficacy in some patients." He said that as many as 40% of patients on infliximab may either become intolerant of the treatment or may stop responding to therapy.
His study group of 18 men and 26 women with a mean age of about 39 years had been treated for Crohn's disease for about 18 years.
In addition to smoking and narcotic use, Shafran said that presence of fibrostenotic disease and steroid use also indicated that patients were unlikely to respond to adalimumab.
He said that in his practice he recommends that:
Among other patients who were not responding to infliximab, however, Shafran said that treatment with adalimumab was able to induce and maintain remission of Crohn's disease symptoms.
American Journal of Gastroenterology
By Ed Susman
October 18, 2010