Filgrastim (r-metHuG-CSF) and its potential use in the reduction of radiation-induced oropharyngeal mucositis: An interim look at a randomized, double-blind, placebo-controlled trial

We wished to determine if filgrastim administration to chemotherapy/radiati on therapy-naive patients receiving external-beam irradiation for head-and- neck malignancies would reduce the incidence and severity of oral/oropharyn geal mucositis. Patients were randomized to receive subcutaneous injections of either filgrastim or placebo beginning on day 1 of radiation and contin uing daily throughout treatment. Study medication was titrated to keep the neutrophil count between 10 x 10(9) and 30 x 10(9)/l. The left and right bu ccal mucosa, hard palate, and posterior pharyngeal wall were scored weekly, by a blinded evaluator using two different scales, and the most severe sco re per week was used in data analysis. Fourteen of a planned 54 patients we re randomized (8 filgrastim, 6 placebo), and were evaluable for a planned i nterim analysis. No statistically significant between-group differences wer e seen in mean worst scores across time using repeated measures analysis of variance (Hickey, p = 0.231; WHO, p = 0.288). At almost all timepoints, ho wever, the worst mean scores were lower in patients treated with filgrastim compared with those in patients treated with placebo, and the number of se vere (i.e., grade 3) mucositis scores was significantly lower in the filgra stim-treated group. Filgrastim may decrease the severity of radiation-induc ed oral/oropharyngeal mucositis.