The study performed by Present and coworkers is by far the largest randomised controlled trial (RCT) assessing the use of medical treatment for fistulas in Crohn’s disease. Bearing in mind that no other drug has been proved to be efficacious in healing this debilitating condition, a complete response rate (i.e., longstanding closure of all fistulas) of 46% among the infliximab treated patients compared with 13% for placebo is impressive. Furthermore, the overall response rate was more than 60% and lasted for around three months. As in the previously published RCT of infliximab for chronic active Crohn’s disease using a single intravenous infusion,1 the best response was attained with the lowest dose tested (5 mg/kg body weight). In Present et al’s study repeated doses of infliximab were given at two and six weeks, but any response occurred before the second infusion had been given in at least half of the patients. In retrospect, one may speculate that a single infusion using the lowest dose would have been enough for a satisfactory response in many patients, but this option was not evaluated. Moreover, the repeated use of the higher (10 mg/kg) dose was less effective but gave rise to a higher frequency of severe adverse events (pneumonia, abscesses).

Although …