sEphB4-HSA in Treating Patients With Kaposi Sarcoma

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.