POLAR BEAR

POLARIX established polatuzumab vedotin in place of vincristine in first-line diffuse large B-cell lymphoma, but it enrolled patients up to 80 and the very old and frail were scarcely represented. The standard for that group is R-miniCHOP, a dose-reduced regimen built for tolerability rather than cure. POLAR BEAR asks the same substitution question in exactly the population POLARIX did not answer for.

Eligibility is deliberately narrow and unusual: 80 years or older, or 75 or older and frail by a simplified comprehensive geriatric assessment. Participants are randomised 1 to 1 between R-miniCHOP and R-pola-miniCHP. Both arms run 18 weeks, with follow-up to 36 months after treatment ends. The primary endpoint is progression-free survival, and primary completion is estimated for 28 December 2025, so the first report is close.

Sites are open in Sweden, Norway, Finland, Denmark, Italy, Australia and New Zealand. Using a geriatric assessment as an eligibility criterion, rather than age alone, is the methodological contribution: it is the kind of trial design that the gap between trial populations and real lymphoma patients has been waiting for.