Korean J Intern Med.  2023 Sep;38(5):734-746. 10.3904/kjim.2022.401.

Rituximab plus multiagent chemotherapy for newly diagnosed CD20-positive acute lymphoblastic leukemia: a prospective phase II study

• Baek DW
• Park HS
• Sohn SK
• Kim DY
• Kim I
• Ahn JS
• Do YR
• Lee SR
• Eom HS
• Lee WS
• Kim SH
• Lee HS
• Lee YJ
• Moon JH
• Lee JH
• Adult Acute Lymphoblastic Leukemia Working Party, the Korean Society of Hematology

• KMID: 2545698
• DOI: http://doi.org/10.3904/kjim.2022.401

Abstract

Background/Aims
We performed a prospective study to determine the efficacy and safety of rituximab including chemotherapy in CD20-positive acute lymphoblastic leukemia (ALL).
Methods
Patients with newly diagnosed ALL, aged ≥ 15 years, were eligible for the study if their leukemic blast cells in bone marrow expressed CD20 ≥ 20% at the time of diagnosis. Patients received multiagent chemotherapy with rituximab. After achieving complete remission (CR), patients received five cycles of consolidation with concomitant rituximab. Rituximab was administered monthly from day 90 of transplantation for patients who received allogeneic hematopoietic cell transplantation.
Results
In patients with Philadelphia (Ph)-negative ALL, 39 of 41 achieved CR (95.1%), the 2- and 4-year relapse-free survival (RFS) rates were 50.4% and 35.7%, and the 2- and 4-year overall survival (OS) rates were 51.5% and 43.2%, respectively. In the group with Ph-positive ALL, all 32 patients achieved CR, the 2- and 4-year RFS rates were 60.7% and 52.1%, and the 2- and 4-year OS rates were 73.3% and 52.3%, respectively. In the Ph-negative ALL group, patients with higher CD20 positivity experienced more favorable RFS (p < 0.001) and OS (p = 0.06) than those with lower CD20 positivity. Patients who received ≥ 2 cycles of rituximab after transplantation had significantly improved RFS (hazard ratio [HR], 0.31; p = 0.049) and OS (HR, 0.29; p = 0.021) compared with those who received < 2 cycles.
Conclusions
The addition of rituximab to conventional chemotherapy for CD20-positive ALL is effective and tolerable (Clinicaltrials. gov NCT01429610).

Keyword

Survival; Leukemia; acute lymphoblastic; Rituximab