Efficacy and Safety Study of SyB L-0501 in Combination With Rituximab in Patients With Untreated, Low-grade B Cell Non-Hodgkin's Lymphoma and Mantle Cell Lymphoma

A dose of 90 mg/m\^2/day of SyB L-0501 is administered on Day 1 and Day 2 as an IV drip infusion, followed by 26-day observation. This is 1 cycle (28 days), which will be repeated for a maximum of 6 times.

A dose of 375 mg/m\^2 of rituximab is administered on Day 1 (Day 0 in Cycle 1 only) as an IV drip infusion, followed by 26-day observation. This is 1 cycle (28 days), which will be repeated for a maximum of 6 times. From Cycle 2, rituximab will be coadministered with SyB L-0501 on Day 1. However, if the investigator or sub-investigator judges that the coadministration is difficult, rituximab may be administered on Day 0.