According to published results of the IESLG-19 trial, adding rituximab to chlorambucil in patients with mucosa-associated lymphoid tissue (MALT) lymphoma did not improve overall survival, despite demonstrating reasonable response rates.
This is a disappointment since the IESLG-19 trial (Randomized Trial of Chlorambucil Versus Chlorambucil Plus Rituximab Versus Rituximab in MALT Lymphoma) was initially launched in an effort to lead to a consensus regarding front-line therapy in MALT lymphoma patients by comparing chlorambucil alone versus chlorambucil plus rituximab in patients not previously given any systemic therapy.
The trial positioned 113 patients in the chlorambucil arm and 114 patients in the combination arm. A third arm was eventually conceived that consisted solely of rituximab, but these findings relate only to the first two arms.
With a median follow-up duration of 62 months, event-free survival (EFS) was 50 percent in the monotherapy arm and 68 percent in the combination arm. Overall response rates were 87 percent for the monotherapy arm and 90 percent for the combination arm. Patients in the combination arm had a higher complete remission rate (78 percent vs 65 percent). A five-year overall survival rate of 89 percent was reported in both arms.
Researchers concluded, "Both treatments were active; the better response rate and EFS obtained with the addition of rituximab did not translate into improved OS."
Source: JCO