Summary

This is a study to determine the maximum tolerated dose (MTD) for CDX-1140 (CD40 antibody),
either alone or in combination with CDX-301 (FLT3L), pembrolizumab, or chemotherapy and to
further evaluate its tolerability and efficacy in expansion cohorts once the MTD is
determined.

Objectives

This study will determine the MTD of CDX-1140 while also evaluating the safety, tolerability
and efficacy of CDX-1140 alone (Part 1) or in combination with CDX-301 (Part 2),
pembrolizumab (Part 3), or chemotherapy (Part 4) in patients with cancer.

Eligible patients that enroll to the dose-escalation portion of the study will be assigned to
one of several dose levels of CDX-1140. The dose-escalation part of the study will test the
safety profile of CDX-1140, alone or in combination with CDX-301, pembrolizumab or
chemotherapy and determine which dose(s) of CDX-1140 will be studied in the expansion
portions of the study.

All patients enrolled in the study will be closely monitored to determine if there is a
response to the treatment as well as for any side effects that may occur.