A Phase 1/2 Open-Label, Multicenter Study Evaluating the Safety and Pharmacokinetics of Escalating Doses of IGM-2323 in Subjects with Relapsed/Refractory Non-Hodgkin Lymphomas

This is a Phase 1/2 study of imvotamab in adult subjects with relapsed or refractory B-cell
Non-Hodgkin Lymphoma. This study will consist of a dose-escalation stage, a combination
stage, and a randomized dose-expansion stage where subjects will be enrolled into
indication-specific expansion cohorts. imvotamab will be administered intravenously (IV).

Additional CD20-positive NHL histologies (e.g. MZL and MCL), may be allowed with Medical
Monitor approval during the Dose-Escalation Phase of the study.

Key Inclusion Criteria:

- > 18 years of age: ECOG PS 0 or 1

- Relapsed or Refractory Follicular Lymphoma (FL), and Diffuse Large B-cell Lymphoma
(DLBCL), Mantle cell Lymphoma (MCL), Marginal Zone Lymphoma (MZL) in dose escalation

- Relapsed or refractory to at least two prior systemic treatment regimens (must include
anti-CD20 chemo-immunotherapy regimen). FL/MZL may be enrolled with a least 2 prior
systemic regimens which must include an anti-CD20, without the need for a prior
chemotherapy regimen)

- At least one bi-dimensionally measurable lesion (>1.5cm in it's longest dimension by
computerized tomography (CT scan)

- Good organ function

- Not eligible for autologous stem cell transplant (DLBCL subjects), due to
chemoresistant disease, medically unfit (organ function), or unwilling.

Key Exclusion Criteria:

- Prior allogeneic transplant

- ASCT within 100 days prior to the first imvotamab administration.

- Lack of response to prior treatment with CAR-T therapy, subjects with less than 3
months from prior CAR-T therapy to first dose of imvotamab, and prior CAR-T therapy
only allowed with Medical Monitor approval.

- Concurrent serious co-morbidities that could limit patients full participation and
compliance.

- Prior CD-targeting bispecific antibodies.

- Prior loncastuximab tesirine.