Ocrelizumab-related neutropenia: Effects of age, sex and bodyweight using the FDA Adverse Event Reporting System (FAERS).

Objective: Neutropenia is a rare complication of anti-CD20 treatment, such as Ocrelizumab (OCR) in Multiple Sclerosis (MS). Using FDA´s Adverse Event Reporting System (FAERS), a post-marketing, open access pharmacovigilance database, we aimed to identify risk factors of neutropenia in OCR-treated patients.

Methods: Data were retrieved from FAERS identifying OCR-treated patients with and without neutropenia. Only data with OCR as the single suspected product were considered. Multivariable logistic regression (MLR) analysis was run to study if MS disease course, age, sex and bodyweight were associated with the risk of neutropenia.

Results: Of 15,313 initial hits, 3177 complete datasets were included in the analysis. MLR demonstrated that MS disease course was not associated, whereas sex (female sex (reference male sex) 0.356, 95%CI 0.145-0.875, p = 0.0124), age (years, 0.909, 95%CI 0.875-0.944, p = 7.4105 × 10) and bodyweight (kilogram, 0.961, 95%CI 0.935-0.988, p = 0.005) were factors associated with OCR-related neutropenia (Nagelkerkes R=0.17, n = 3177). No deaths were reported for identified neutropenia cases.

Conclusion: Using FAERS, we identified male sex, younger age and lower bodyweight as factors associated with OCR-related neutropenia. With the limitations inherent to this open data source, our data need prospective validation, but elucidate potential factors for a personalized side effect profiling.