Acalabrutinib Plus Rituximab for the Treatment of Elderly or Low- to Intermediate-Risk Younger Untreated Mantle Cell Lymphoma

This study is testing whether a combination of acalabrutinib (a targeted BTK inhibitor pill) and rituximab (an infused immunotherapy) can effectively treat mantle cell lymphoma (a type of blood cancer) without needing intensive chemotherapy, in elderly patients or in younger lower-risk patients. **You may be eligible if...** - You are 18 or older with confirmed mantle cell lymphoma (a specific type of B-cell lymphoma) - You have not previously received any treatment for lymphoma - Your cancer is Stage II–IV - If you are younger than 65, your cancer meets certain lower-risk criteria (specific genetic and tumor characteristics) **You may NOT be eligible if...** - You have received prior treatment for this lymphoma - Your cancer has transformed or has high-risk features (for younger patients) - You have significant organ problems or other blood cancers - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.