OBJECTIVES: AREVEDECY was a real-world study of relapsed/refractory chronic lymphocytic leukemia (R/R CLL) patients treated with venetoclax and venetoclax+rituximab in Belgium. After reporting on positive effectiveness results, here we look at the reported usage (dosing, interruptions, discontinuation) of Venetoclax in the study.

METHODS: The AREVEDECY study was a retrospective chart review in the period September 2019-July 2023. In the study, 117 patients from 9 hospital centers were included.

RESULTS: The overall response rate (ORR) in the total sample was 90%. After 24 months, OS and PFS rates in the total group were 81% and 80% respectively. At the end of the ramp-up, 93/117 (79.5%) patients reached 400 mg, 13/117 (11.1%) reached 200 mg, 10/117 (8.5%) reached 100 mg and 1/117 (0.9%) reached 50 mg. Further dose reductions were reported in 34 patients (29.1%) while 20 patients (17.1%) reported treatment interruption (median duration: 16 days). Dose reduction and treatment interruption were mostly due to non-TLS-related adverse events (e.g. neutropenia, pneumonia, etc.). Average on-treatment dosing intensity was 328.5 mg. Treatment discontinuation was reported in 46 (39%) patients, mostly due to non-TLS-related adverse events. Twelve months after treatment start, 79% did not report yet discontinuation according to the KM estimate. After 18 months, this number dropped to 65%. The median time-to-treatment discontinuation was 24.6 months, suggesting around 50% of patients completed the normal venetoclax treatment duration (see Figure 1). Among a subgroup of patients having initiated Venetoclax > 765 days ago, 47% completed the normal on-treatment period without progression, in line with the above result.

CONCLUSIONS: In a Belgian real-world setting, Venetoclax (alone or in combination with ritixumab) dosing intensity was 328.5mg and almost 50% of patients completed the normal venetoclax treatment duration. Non-TLS-related adverse events were the most cited as trigger for dosing reductions, treatment interruptions or discontinuations.