Zanubrutinib, Lenalidomide Plus R-CHOP (ZR 2-CHOP) As the First-Line Treatment for Diffused Large B-Cell Lymphoma (DLBCL)
Authors: Zhu Huayuan , Sha Yeqin , Wu Wei , Qiu Jingyan , Yang Yilian , Peng Chen , Ding Chongyang , Wang Zhen , Fan Lei , Xu Wei , Li Jianyong 
Published: November 2021

Abstract
Introduction
To evaluate the safety and efficacy of zanubrutinib, lenalidomide plus R-CHOP (ZR 2-CHOP) as the first-line treatment for DLBCL patients, we conducted this single-arm retrospective observational study.
Methods
Treatment-naïve patients with DLBCL(including but not limited to double-hit, double expression) aged 18 to 75 years were enrolled.ZR 2-CHOP was given as follows, Oral zanubrutinib was given continuously (160 mg twice daily) from Day 0, lenalidomide 25 mg daily Day 1-7. Patients were administered intravenously rituximab (375 mg/m 2 Day 0), cyclophosphamide (750 mg/m 2 Day 1), doxorubicin (50 mg/m 2 Day 1), vincristine (1.4 mg/m 2 Day 1), and oral prednisone (100 mg Day 1-5). All patients were recommended to receive 6 cycles of ZR 2-CHOP (R-CHOP or R 2-CHOP were allowed in cycle 1-2 due to poor physical condition at treatment) and patients older than 70 years old were administered ZR 2-miniCHOP (Figure 1). CT or PET-CT scans were applied to mid-term efficacy and PET-CT scan was conducted after 6 cycles. ctDNA was dynamically detected before treatment, after 3 and 6 cycles to evaluate tumor mutational burden. The primary endpoint was complete response ratio (CRR) at mid-term and after 6 cycles. The secondary endpoint was overall response rate (ORR), ctDNA dynamics and adverse events (AE). AEs were graded based on CTCAE (version 5.0).
Results
12 treatment-naïve DLBCL patients diagnosed in Pukou CLL Center were enrolled in this cohort between July 2020 and June 2021. The median age was 56 years old and all patients had ECOG-PS ≤2. 1 patient (1/12) was diagnosed as double-hit DLBCL and 9 patients (9/12) as double-expression. 10 patients were non-GCB and 2 were GCB. 7 patients were classified as high-intermediate and high-risk group according to NCCN-IPI (Table 1). At data cutoff (1st July, 2021), the median follow-up was 8 months (3-12 months) with all patients have completed at least 3 cycles and mid-term assessment has been conducted. The ORR was 100.0%, with 10 patients achieved CR and 2 patients achieved PR (both two patients received R-CHOP regimen in cycle 1/cycle 1-2 due to poor physical condition at initial treatment, Figure 1). 10 patients have received 6 cycles, all of them achieved CR (Figure 2). ctDNA was dynamically detected in six patients. The median number of detectable ctDNA mutation among six patients was 8 (0-12) with two patients classified as MCD subtype and one patients as EZB subtype. All six patients showed undetectable ctDNA after 3 cycles. During end of treatment follow-up, one patient (triple-hit, EZB) who scheduled to receive auto-SCT underwent disease progression 4 months later and reemergence of ctDNA showed previous homologous clones. The most common hematological toxicity events were lymphocytes count decreased, neutrophil count decreased, thrombocytopenia and anemia, with 3-4 level occurrence rate was 66.7%, 25.0%, 25.0% and 16.7%. The most common non-hematological toxicity events were nausea, fatigue and anorexia. One patients discontinued oral zanubrutinib and lenalidomide in last two cycles due to drug rash.
Conclusion
ZR 2-CHOP could attain high CR rate and ctDNA clearance in TN DLBCL, including patients with DEL and/or high-risk. The overall tolerability was manageable. ZR 2-CHOP could be one of the promising choice for TN DLBCL.
Figure 1 Figure 1.

Disclosures
No relevant conflicts of interest to declare.

OffLabel Disclosure:
Zanubrutinib was used in the initial treatment of high-risk DLBCL.