PRIMARY OBJECTIVES:~I. To evaluate the clinical response and toxicity of recombinant EphB4-HSA fusion protein (sEphB4-HSA) (at initial dosing of 15 mg/kg every 2 weeks) in participants with Kaposi sarcoma.~SECONDARY OBJECTIVES:~I. To assess the safety of sEphB4-HSA in participants with Kaposi sarcoma (KS). II. To determine trough level exposure of sEphB4-HSA and correlate with tumor response.~III. To characterize the pharmacodynamics of sEphB4-HSA and correlate these effects with clinical response.~IV. Effects on viral replication and gene expression of human herpes virus-8 (HHV-8).~V. Changes in vascular endothelial growth factor (VEGF)-Notch-EphrinB2 angiogenic pathway.~VI. Effects on immune response and modulation. VII. Effects on tumor cell apoptosis and proliferation. VIII. Effects on sEphB4-HSA on human immunodeficiency virus (HIV) plasma viral loads in participants with HIV.~IX. To archive peripheral blood mononuclear cells (PBMCs) and tissue samples to be used in conjunction with samples collected in subsequent trials of sEphB4-HSA for future studies including identification of biomarkers predictive of response.~X. To evaluate the clinical response and toxicity of sEphB4-HSA (at increased dosing of 10 mg/kg every week) in participants with KS.~TERTIARY OBJECTIVES:~I. Describe baseline quality of life (QOL) scores, using the functional assessment of HIV Infection (FAHI) + Kaposi sarcoma (KS) questionnaire, in participants with KS, and explore changes in QOL of participants on treatment with sEphB4-HSA.~OUTLINE:~Patients receive recombinant EphB4-HSA fusion protein intravenously (IV) over 1 hour on days 1 and 15. Patients with disease progression after 2 or more courses who have not experienced toxicity may receive recombinant EphB4-HSA fusion protein IV over 1 hour on days 1, 8, 15, and 22. Treatment repeats every 28 days for up to 12 courses in the absence of further disease progression or unacceptable toxicity.~After completion of study treatment, patients are followed up for 1 month; patients with partial response or better are followed up every 3 months for up to 1 year.
This phase II trial studies recombinant EphB4-HSA fusion protein (EphB4-HSA) in treating patients with Kaposi sarcoma. Recombinant EphB4-HSA fusion protein may block the growth of blood vessels that provide blood to the cancer, and may also prevent cancer cells from growing.