Conclusions
Both double and triple combinations showed enhanced survival versus ibrutinib alone. Ibrutinib insensitivity can be disrupted by alisertib plus ibrutinib in MCL.
Results
Alisertib, an AK-A inhibitor, has anti-tumor activity in relapsed/refractory (r/r) MCL patients. We evaluated alisertib plus ibrutinib in MCL to abrogate ibrutinib resistance. Alisertib plus ibrutinib was therapeutically synergistic on both Granta-519 insensitive to ibrutinib and JeKo-1 cells sensitive to ibrutinib. Alisertib decreased PI-3K, BTK, p38, HCK, and RSK kinases, indicative of its multipotent effect on cellular proliferation and growth. A mouse xenograft model of Granta-519 demonstrated that alisertib plus ibrutinib had a comparable anti-tumor response to ibrutinib plus rituximab. However, alisertib plus ibrutinib plus rituximab demonstrated significantly stronger tumor growth inhibition than the doublets. Conclusions: Both double and triple combinations showed enhanced survival versus ibrutinib alone. Ibrutinib insensitivity can be disrupted by alisertib plus ibrutinib in MCL.