For a study, the phase I/II AU-003 research showed that zanubrutinib therapy produces clinically significant and sustained responses in patients with treatment-naive (TN) or relapsed/refractory (R/R) chronic lymphocytic leukemia/small lymphocytic lymphoma, with acceptable safety and tolerability. With a median follow-up of 472 months, researchers presented updated safety and effectiveness data for 123 patients. Patients were given zanubrutinib in doses of 160 mg twice a day (81 patients), 320 mg once daily (40), or 160 mg once daily (2). Discontinuations were infrequent owing to adverse effects or disease progression. 

The overall response rate (ORR) was 95.9% (TN, 100%; R/R, 95%), with 18.7% of respondents completing the survey (CR). In 85.7% of cases, the reaction was still happening after three years. In patients with a del(17p)/tumour protein p53 mutation, the ORR was 87.5% (CR 16.7%). The progression-free survival estimates were 90% (TN, 90%; R/R, 91%) and 83% (TN, 81%; R/R, 83%) after 2 and 3 years, respectively. Neutropenia (15.4%), pneumonia (9.8%), hypertension (8.9%), and anemia (6.5%) were the most often reported Grade 3 adverse events. 

Atrial fibrillation, severe hemorrhage, Grade 3 neutropenia, and Grade 3 infection all reduced in yearly occurrence over time. With a median follow-up of 4 years, responses to zanubrutinib treatment were still clinically relevant and persistent, and long-term tolerability was still present.