Brukinsa vs Imbruvica

Brukinsa and Imbruvica are both BTK inhibitors reviewed for B-cell malignancies. Brukinsa is indicated for chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) and Waldenström’s macroglobulinemia (WM), with its monotherapy for adult patients with CLL being a key focus. Imbruvica is indicated for the treatment of patients with Waldenström’s macroglobulinemia (WM), adult patients with chronic graft versus host disease (cGVHD) after failure of one or more lines of systemic therapy, and chronic lymphocytic leukemia (CLL) in various settings, including those who have received at least one prior therapy or have a 17p deletion.

Regulators reviewed Brukinsa, noting a Complete Response (CR) of 59 in one assessment and a VGPR/CR rate of 32.4. The Duration of Overall response event-free rate at 24 months for Brukinsa was reported as 82.2. For Imbruvica, the Overall response rate (CR+VGPR+PR) per IRRC assessment was 61.9%, with a 95% CI of 49% to 74%. The median duration of Imbruvica exposure in CLL Study 2 was 8.6 months, compared to 5.3 months for ofatumumab exposure in the same study.

These drugs were studied in separate trials with different designs, patient populations, and timepoints. The endpoints, comparators, and specific cohorts varied between the studies. For example, Brukinsa's review included data from a WM cohort comparing it to Ibrutinib for adverse events, while Imbruvica's review detailed response rates and exposure durations in CLL studies. The figures presented are from each drug's own regulatory review documents and are not head-to-head comparisons; therefore, no implication of superiority for either drug should be drawn from these distinct findings.