MEN1703

The goal of the study is to assess the safety and anti-lymphoma activity of MEN1703 (Dapolsertib hydrochloride) when given as a single-agent or combined with glofitamab to patients with relapsed/refractory (R/R) aggressive B-cell non-Hodgkin lymphoma. The study will be open to groups at the same time: * Group 1 - patients who have not had anti-CD3xCD20 bispecific antibody therapy but who have had at least 2 prior lines of systemic treatment for aggressive B-cell non-Hodgkin lymphoma * Group 2 - patients who have exhausted all standard treatment options including at least 2 prior lines of systemic treatment for aggressive B-cell non-Hodgkin lymphoma Group 1 patients will be treated for a maximum of 12 cycles. One cycle is 21 days. Group 2 with be treated until the disease progresses, therefore treatment duration is dependent on the number of treatment cycles a participant receives prior to progression.