• Capability of understanding the purpose of the study and have given written informed consent.

• Age greater than or equal to 18 years

• Histologically or cytologically confirmed relapsed or refractory MCL

• r/r MCL patients following standard first line chemotherapy who have received at least one prior regimen including ibrutinib

• If the participant has received prior bendamustine, response duration must have been \> 1 year

• Presence of at least one lymph node or mass measurable for response

• Life expectancy of at least 24 weeks

• ECOG 0-2

• Adequate hematological, renal and hepatic function unless inadequate function is due to underlying disease