Performance of the pegfilgrastim on-body injector as studied with placebo buffer in healthy volunteers

Objective: The pegfilgrastim on-body injector (OBI) is a single-use, disposable, battery powered injector that is designed to automatically deliver a single subcutaneous dose of pegfilgrastim beginning approximately 27 hours after activation and continuing over approximately 45 minutes. In this open- label study, we assessed performance of the OBI delivering placebo buffer in healthy volunteers. Research design and methods: Healthy men and women aged 18-55 years, with a body mass index of 18-35 kg/ m(2), were enrolled. OBIs were activated by filling them with placebo buffer, and two injectors were applied concurrently to each subject: one to the abdomen and one to the back of the upper arm. Subjects were monitored for substantial leakage during and after administration. Main outcome measures: The primary endpoint of the study was successful delivery of placebo buffer based on a composite of the following: no substantial leakage during or after administration, green status light indicator on the injector during and after administration, and fill indicator bar at the empty position after administration. The secondary endpoint was the incidence of treatment-emergent adverse events (AEs). Results: Of the 150 subjects enrolled, 149 (99.3%) completed the study. Study subjects were 48.0% men, and 52.0% women; 47.3% were white, 35.3% black or African American, 12.7% Asian, and 4.7% other. Mean (SD) age was 35.9 ( 10.8) years. Of the 297 total deliveries, 292 98.3%) were considered successful: 147/ 149 (98.7%; 95% confidence interval [CI]: 95.2%-99.6%) to the abdomen and 145/148 (98.0%; 95% CI: 94.2%-99.3%) to the back of the upper arm. Five deliveries were considered unsuccessful: two due to hazard alarms, and three due to substantial leakage. The most common treatmentemergent AEs (in > 2% of subjects overall) by preferred term were medical device site reaction (20.7%), catheter-site hemorrhage (8.7%), and headache (3.3%). No serious AEs were reported. Conclusions: The pegfilgrastim OBI was well tolerated, and deliveries of placebo buffer were successful 98.3% of the time. The generalizability of these results may be limited by the conduct of this study in healthy subjects in a controlled environment.