A Study of MGD013 in Patients With Unresectable or Metastatic Neoplasms

This is a Phase 1, open-label, dose escalation and cohort expansion study designed to
characterize the safety, tolerability, PK, PD, immunogenicity, and preliminary antitumor
activity of MGD013 administered by IV infusion on every 2 weeks. The study consists of a Dose
Escalation Phase to determine the MTD or maximum administered dose (MAD) of MGD013 if no MTD
is defined, followed by a Cohort Expansion Phase to further define the safety and initial
antitumor activity of MGD013 with the dose established in the Dose Escalation Phase.

In the Dose Escalation Phase, MGD013 will be evaluated in sequential escalating flat doses in
successive cohorts of 1 to 6 patients each. Upon completion of the Dose Escalation Phase, a
Cohort Expansion Phase will be initiated at the MTD/MAD.

Patients with unresectable, locally advanced or metastatic solid tumors of any histology will
be enrolled in the Dose Escalation Phase. The Cohort Expansion Phase will be limited to
selected cohorts of patients with unresectable, locally advanced or metastatic solid tumors
or hematologic malignancies for whom there is no available therapy likely to confer clinical
benefit.

Inclusion Criteria:

- Histologically proven, locally advanced unresectable or metastatic solid tumors (or
hematologic malignancies, Cohort Expansion only) for whom no approved therapy with
demonstrated clinical benefit is available or standard treatment was declined.

- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

- Life expectancy ≥ 12 weeks

- Measurable disease

- Tissue specimen available for retrospective analysis of PD-1, PD-L1, LAG-3, and MHC-II
expression

- Acceptable laboratory parameters

Exclusion Criteria:

- Symptomatic central nervous system (CNS) metastases or primary CNS lymphoma

- History of allogeneic bone marrow, stem-cell, or solid organ transplant

- History of known or suspected autoimmune disease with the specific exceptions of
vitiligo, resolved childhood atopic dermatitis, psoriasis not requiring systemic
treatment (within the past 2 years), and patients with a history of Grave's disease
that are now euthyroid clinically and by laboratory testing.

- Treatment with any systemic chemotherapy within 3 weeks prior to the initiation of
study drug; treatment with biologics or investigational therapy within the 4 weeks
prior to the initiation of study drug.

- Major surgery within 4 weeks prior to the initiation of study drug.

- Prior treatment with combination of monoclonal antibodies against PD-1 and LAG-3
(Cohort Expansion only).

- Treatment with radiation therapy within 2 weeks prior to the initiation of study drug.

- Clinically significant cardiovascular disease.

- QTcF prolongation > 480 milliseconds

- Clinically significant pulmonary compromise, including a requirement for supplemental
oxygen use to maintain adequate oxygenation.

- Active pneumonitis or history of non-infectious pneumonitis.

- Clinically significant gastrointestinal disorders.

- Evidence of active viral, bacterial, or systemic fungal infection requiring parenteral
treatment within 7 days prior to the initiation of study drug.

- Known history of positive testing for human immunodeficiency virus or history of
acquired immune deficiency syndrome.

- Known history of hepatitis B (except in hepatocellular carcinoma) or hepatitis C
infection or known positive test for hepatitis B surface antigen, hepatitis B core
antigen, or hepatitis C polymerase chain reaction (PCR)

- Vaccination with any live virus vaccine within 4 weeks prior to the initiation of
study drug administration. Inactivated annual influenza vaccination is allowed

- Dementia or altered mental status that would preclude understanding and rendering of
informed consent