(C-217) Incidence of Cataract Among Patients Exposed to FGFR Inhibitors in the Real-World

Background: FGFR1-4 isoforms are differentially expressed throughout various structures in the eye which could help explain the susceptibility of off-target ocular adverse events (AEs) seen with FGFR inhibitor (FGFRi) therapy. Although ocular toxicities have been reported in clinical trials of FGFR inhibitors, limited data are available from the real-world setting.

Objectives: To estimate the incidence of cataract among patients exposed to an FGFRi using real-world data.

Methods: The incidence of cataract among patients who initiated an FGFRi (i.e. erdafitinib, pemigatinib, futibatinib, or infigratinib) was estimated in US real-world databases: Merative™ MarketScan® Commercial Claims and Encounters Database (CCAE), Merative™ MarketScan® Medicare Supplemental and Coordination of Benefits Database (MDCR), Merative™ MarketScan® Multi-State Medicaid Database (MDCD), Optum’s de-identified Clinformatics® Data Mart Database (Clinformatics®), IQVIA™ PharMetrics® Plus (PharMetrics®), and Optum® de-identified Electronic Health Record data set (Optum® EHR) from 2019 to the latest data available. The outcome was defined as the earliest event of cataract, excluding diagnosis codes implying non-drug causes of cataract such as hereditary/congenital, diabetes mellitus and other systemic diseases, trauma, and complications of extraction. Incidence proportions (IP) and incidence rates (IR) were calculated as the number of people with newly diagnosed cataract events observed during the time at risk divided by the total number of people at risk (for IP) or the total person-years (PY) at risk (for IR). The time at risk was defined as 1 day after index date (FGFRi initiation) up to 2 years. Incidence was stratified by age groups (0-17, 18-34, 35-44, 45-54, 55-64, 65-74, and ≥75 years).

Results: Across the databases, the number of patients initiating a FGFRi ranged from 25 (MDCD) to 329 (Optum® EHR). The FGFRi population characteristics showed a mean age >55 years and a higher proportion of females (56.6-63.9%). In the 3 US claims databases with sufficient number of cases to estimate incidence, the 2-year IR and IP ranged from 35.7 to 58.6 per 100 PY and 19.4 to 30.1 per 100 persons, respectively. In the analysis stratified by age, there were small numbers of patients at risk and of outcomes for some age groups; however, there appeared to be higher rates of cataract in patients aged ≥55 years compared to all ages in the claims databases (e.g. 59.2 vs 35.7 per 100 PY in PharMetrics®).

Conclusions: These findings from real-world data show that patients exposed to a FGFRi have a 2-year incidence rate of cataract ranging between 35.7 and 58.6 per 100 PY. Further studies are warranted to better understand cataract formation in patients receiving FGFRi therapy.