BeOne Medicines (Nasdaq: ONC) reported positive topline results from the Phase III MANGROVE trial showing that zanubrutinib (Brukinsa) plus rituximab reduced the risk of progression or death by 43% compared with bendamustine plus rituximab (BR) in previously untreated mantle cell lymphoma (MCL), fulfilling a post-marketing requirement tied to zanubrutinib's 2019 accelerated FDA approval in the disease. The result matters because it is the first Phase III trial to demonstrate that a chemotherapy-free BTK inhibitor-based regimen can outperform standard chemoimmunotherapy in the frontline MCL setting — a question that has remained unanswered despite years of BTK inhibitor use in the disease.
The MANGROVE trial enrolled 510 patients across 176 global sites and compared zanubrutinib at 160 mg twice daily plus rituximab followed by zanubrutinib monotherapy against six cycles of BR. At a prespecified interim analysis, the study met its primary endpoint of progression-free survival (PFS) as assessed by an independent review committee, with a hazard ratio of 0.57 (95% CI, 0.43–0.76; p<0.0001). Overall survival, a key secondary endpoint, was immature at the time of analysis but showed a trend favoring the zanubrutinib arm; it will be formally tested at the final analysis. The safety profile was consistent with the established profiles of both agents, with no new signals identified.
Competitive context
The most relevant approved comparator in this setting is AstraZeneca's Calquence (acalabrutinib) in combination with BR, which received FDA approval in January 2025 for transplant-ineligible patients with previously untreated MCL, based on the Phase III ECHO trial. That regimen adds a BTK inhibitor to chemotherapy rather than replacing it — a fundamentally different strategic position from MANGROVE. Cross-trial comparisons are limited by differences in patient populations, trial design, and follow-up duration, but MANGROVE's chemotherapy-free design represents a meaningful clinical distinction: patients in the experimental arm were spared approximately two years of infusions, with no rituximab maintenance required after the initial treatment period.
In the relapsed or refractory setting, BeOne's own sonrotoclax (Beqalzi) received FDA accelerated approval in May 2026 as a BCL-2 inhibitor for MCL after at least two prior lines including a BTK inhibitor, positioning BeOne with potential assets across multiple lines of MCL therapy. Eli Lilly's Jaypirca (pirtobrutinib), a non-covalent BTK inhibitor approved for relapsed or refractory MCL post-BTK inhibitor, operates in a distinct later-line setting and does not directly compete in the frontline space.