Recombinant EphB4-HSA Fusion Protein and Pembrolizumab, MK-3475

Inclusion Criteria: * One of the following: * Locally advanced or metastatic non-small cell lung cancer that has progressed after at least 1 line of platinum based chemotherapy * Patients may have received up to 2 prior lines of chemotherapy * Patients with actionable alterations in EGFR/ALK/ROS1/BRAF must also have progressed after treatment with a tyrosine kinase inhibitor appropriate for their genetic alteration * Untreated patients who refuse 1st line platinum based chemotherapy are also eligible * Squamous cell carcinoma of the head and neck whose disease has progressed after at least 1 line of platinum based chemotherapy * Patients may have received up to 2 prior lines of chemotherapy * Untreated patients who refuse 1st line platinum based chemotherapy are also eligible * Patients who relapse within 6 months of adjuvant cisplatin based concurrent chemoradiation, or neoadjuvant cisplatin based therapy can be considered eligible without an additional course of platinum chemotherapy for relapsed disease * Patients may have either locally recurrent or distant metastatic disease * Be willing and able to provide written informed consent/assent for the trial * Have measurable disease based on Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 * Be willing to provide tissue from a newly obtained core or excisional biopsy of a tumor lesion after 2 cycles of therapy * Have a performance status of 0 or 1 on the Eastern Cooperative Oncolog…