Janssen-Cilag International (Janssen) has reported positive data from a four-year follow-up period of its Phase III RESONATE trial of Imbruvica (ibrutinib) to treat relapsed / refractory (R/R) chronic lymphocytic leukaemia (CLL) patients.
Ibrutinib is an inhibitor of Bruton's tyrosine kinase (BTK) and also jointly developed and commercialised by Janssen Biotech and AbbVie’s Pharmacyclics.
It forms a covalent bond with BTK and blocks the transmission of cell survival signals in malignant B-cells, resulting in cancer cells destruction and delay in disease progression.
The results from a median follow-up of 44 months showed a 59% three-year progression-free survival (PFS) rate with ibrutinib compared to 3% in the case of atumumab.
Funded by Pharmacyclics, the Phase III randomised, multi-centre, open-label, international trial evaluated 420mg of once-daily oral ibrutinib over 24 weeks in 391 patients who had previously received a minimum of one type of therapy and were not considered eligible for treatment with a purine analog.
In 2014, the trial’s primary results indicated that the primary and key secondary endpoints had been met.
Janssen Europe, Middle East and Africa haematology therapeutic area lead Dr Catherine Taylor said: “With up to four-year follow-up data, we are continuing to grow the evidence base for ibrutinib and we continue to be impressed by its durability and control for patients with relapsed or refractory chronic lymphocytic leukaemia.”
During the follow-up period, the PFS was found to be consistent across the entire baseline disease and patient characteristics, specifically in patients with genetic mutation deletion 11q (del11q).
The overall response rate (ORR) was observed to be 91% and the complete response or complete response with incomplete bone marrow recovery (CR/CRi) rate was 9%.
The analysis of the adverse event (AE) profile of ibrutinib showed a decrease in the majority of Grade ≥3 AE’s incidence from year one to years two and three.