Human Genome Sciences, Inc. (HGSI) reported that a Phase 2 clinical trial of systemically administered repifermin for the treatment of cancer therapy-induced mucositis did not meet its primary endpoint.

According to the study protocol, efficacy was measured as the percentage of patients experiencing grade two to four mucositis at the highest dose of repifermin administered. The trial was designed to show a forty per cent relative reduction in the incidence of grade two to four mucositis. The percentage of patients treated with the highest dose of repifermin, 75 micrograms (mcg) per kilogram, who experienced grade two to four mucositis was not statistically significantly different from placebo. A total of ninety-two patients with multiple myeloma, who were scheduled to receive two autologous hematopoietic stem cell transplantations, were randomized in the single-center, double-blind, crossover, dose-escalation Phase 2 clinical trial. Fifty-one of the patients received either placebo or the highest dose of repifermin (75 mcg/kg) intravenously daily for three days prior to their chemotherapeutic conditioning regimen, and daily for seven days following their first autologous hematopoietic stem cell transplantation. After a period of approximately three to six months, patients who had been administered repifermin for their first transplantation were administered placebo prior to and following their second transplantation. Patients who had received placebo for their first transplantation were administered repifermin prior to and following their second transplantation. Repifermin was well tolerated across all doses of repifermin administered with a safety profile similar to placebo.

David Stump, executive vice president, Drug Development, said, "Given repifermin's demonstrated safety and signs of efficacy in prior studies in this patient population, we are disappointed with the results from this trial. Based on the new data, we have decided not to proceed with further development of repifermin. We continue to have a rich pipeline of novel protein and antibody drugs in clinical and late-stage preclinical development, and will continue to advance our clinical development pipeline with a primary focus in oncology and immunology/infectious disease."