OBJECTIVES: The pegfilgrastim on-body injector (OBI) facilitates the time-released administration of pegfilgrastim the day after chemotherapy, as clinically recommended for the prevention of febrile neutropenia. As patients undergo multiple chemotherapy cycles and receive a new OBI device each cycle, estimation of device failure rates should be normalized to the number of devices used. Past studies reported OBI failure rates up to 6.9%. Error rates are overestimated when they are based on per patient rather than per device or chemotherapy cycle. This overestimation can negatively influence physicians’ perception of the OBI. As over 1 million patients have received the OBI, we evaluated OBI device failures in the postmarketing setting and in a large prospective observational study.

METHODS: We report OBI failures in patients receiving chemotherapy assessed in two different data sources. Medication errors with the OBI, defined as missed or incomplete dose, dose delay or dose interruption of pegfilgrastim due to user error or device malfunction, were assessed utilizing post market surveillance data from the European Union (EU) (reporting period: 15 May 2018‒15 May 2021). Device failures of the OBI were assessed in a prospective observational study conducted in the United States (enrollment: 07 November 2018–09 April 2020); device failure was physician-reported and defined as not functioning as intended.

RESULTS: The post market surveillance data revealed that the reporting rate of medication errors with the OBI within the EU was 0.58% (161 events in 27,666 distributed devices) over 3 years. In the prospective observational study (n=1,624), 6 failures were reported in 6,087 cycles (0.1%).

CONCLUSIONS: Experience with >30,000 OBIs in the EU and US suggest medication errors (0.58%) and reported failures (0.1%) are lower than previously reported. The benefit-risk profile of the OBI remains favorable.