Major Complications and Adverse Events Related to Use of SpaceOAR Hydrogel for Prostate Cancer Radiotherapy

To determine the prevalence and severity of SpaceOAR-related adverse events using the Manufacturer and User Facility Device Experience (MAUDE) database.

We analyzed SpaceOAR-related adverse event reports in the Manufacturer and User Facility Device Experience (MAUDE) database from January 2015 to May 2023. For each report, the event type, associated device and patient problems, event description, event timing, and event severity stratified by the Common Terminology Criteria for Adverse Events version 5.0 (CTCAE) grading system were recorded.

From 2015 to 2022, 206,619 SpaceOAR devices were sold. From January 2015 to May 2023, we identified 981 reports describing 990 SpaceOAR-related adverse events. Malfunctions were the most common event type (N = 626), followed by patient injuries (N = 350) with few reported deaths (N = 5). Device positioning problems were the most frequent device issue (N = 686). Pain was the most reported patient problem (N = 216). Abscesses and fistulas related to the device were each reported in 91 events. A noteworthy portion of relevant adverse events occurred before the initiation of radiation (N = 35, 22.4%), suggesting the device, rather than the radiation, was responsible. In total, 470 (50.2%) and 344 (36.7%) of the adverse events were CTCAE grade 1 and 2, respectively. There were 123 (13.1%) events that were CTCAE grade ≥3.

We identified multiple reports of SpaceOAR-related adverse events, many of which are more serious than have been reported in clinical trials. While SpaceOAR use is common, suggesting these events are rare, these data highlight the need for continued postmarket surveillance.