The eligible patients will be treated with Orelabrutinib combined with Rituximab, high-dose Methotrexate and Dexamethasone during induction treatment (6-8 cycles; 21 days/cycle): Rituximab 375 mg/m2, intravenous infusion, d1; HD-MTX 3.5 g/m2 intravenous infusion (3h), d2; Dexamethasone 10-15 mg, iv, d1-4. Orelabrutinib will be given 72h after MTX infusion or until MTX clearance. The study will investigate optimal dose combination of Orelabrutinib and MTX implementing BOIN waterfall design. The starting dose of Orelabrutinib is 150 mg/d and the dose will be escalated to 200 mg/d, throughout the whole cycle. Meanwhile, the starting dose of MTX is 3g/m2 and will be escalated to 5g/m2, throughout induction phase. Dose escalation and movement in dose matrix will be determined by BOIN algorithm. For CR/CRu patients after completion of induction treatment, daily Orelabrutinib will be administered as maintenance treatment for up to 1 year or until disease progression, intolerable toxicity, death, informed consent withdrawal or lost of follow up (whichever occurs first). Patients will be evaluated every 2 cycles during induction therapy and every 12 weeks during maintenance therapy.
This is a single arm, single center, open label pilot study of Orelabrutinib combined with Rituximab, high-dose (HD) Methotrexate and Dexamethasone in newly-diagnosed primary central nervous system lymphpoma (PCNSL). The purpose is to evaluate the safety and to find the optimal dose of Orelabrutinib and Methotrexate in this combination treatment for newly-diagnosed PCNSL patients.