This is a phase 1, single-center, open-label, single-arm trial in patients with indolent B-cell non-Hodgkin lymphoma otherwise appropriate for bendamustine-rituximab as initial or subsequent line of therapy. Patients will receive the of rituximab and bendamustine in combination with escalating doses of vincristine sulfate liposome injection (Marqibo®). The objective of this study is to assess safety of this combination by establishing the maximum tolerated dose of vincristine sulfate liposome injection (Marqibo®) in the combination.