Recombinant human interleukin 11 and bacterial infection in patients with haemological malignant disease undergoing chemotherapy: A double-blind placebo-controlled randomised trial

Background: Bacteraemia in patients with haemological malignant disease causes substantial morbidity. Recombinant human interleukin 11 (rhIL-11) prevents gastrointestinal epithelial disintegrity and has immunomodulatory actions. Our aim was to ascertain whether or not treatment with rhIL-11 can prevent gut-associated infections. Methods: We did a double-blind placebo-controlled randomised trial, to which we enrolled 40 patients with haemological malignant disease who were undergoing chemotherapy. Patients received either rhIL-11 50 μg/kg (n=20) or placebo (n=20) daily by subcutaneous injection from the day before the start of chemotherapy until resolution of neutropenia or for 21 days, whichever was longer. Our primary outcome measure was a reduction in bacteraemia. Analysis was by intention to treat. Findings: Significantly fewer patients who received rhIL-11 rather than placebo developed bacteraemia, particularly of gastrointestinal origin: the proportion of patients with at least one positive blood culture was 0.65 and 0.25, respectively (p=0.02). The numbers of patients (placebo vs rhIL-11) for each number of distinct isolates were: no organism isolated seven versus 15, one organism nine versus four, two organisms two versus one, three organisms one versus none, and four organisms one versus none (p=0.01), suggesting a lower bacterial load in the rhIL-11 than in the placebo group. Time to first bacteraemic event was longer in patients who received rhIL-11 (p=0.03) than in those who received placebo. Interpretation: rhIL-11 reduces the frequency and load of bacteraemia in patients with haemological malignant disease undergoing chemotherapy, possibly by gastrointestinal cytoprotective or immunological mechanisms.