Obatoclax Mesylate and Topotecan Hydrochloride in Treating Patients With Relapsed or Refractory Small Cell Lung Cancer or Advanced Solid Tumors

PRIMARY OBJECTIVES: I. Determine the maximum tolerated dose, recommended phase II dose, and toxicity profile of obatoclax mesylate when administered with topotecan hydrochloride in patients with advanced solid tumors. (Phase I) II. Determine the response rate in patients with relapsed or refractory small cell lung cancer treated with obatoclax mesylate and topotecan hydrochloride. (Phase II) SECONDARY OBJECTIVES: I. Evaluate the expression of pro- and anti-apoptotic proteins which may correlate with obatoclax mesylate sensitivity or resistance. OUTLINE: This is a phase I dose-escalation study of obatoclax mesylate followed by a phase II study. PHASE I (solid tumor): Patients receive obatoclax mesylate IV over 3 hours on day 1 OR days 1 and 3 and topotecan hydrochloride IV over 30 minutes on days 1-5. Courses repeat every 3 weeks in the absence of disease progression or unacceptable toxicity. PHASE II (small cell lung cancer): Patients receive obatoclax mesylate and topotecan hydrochloride at the recommended phase II dose (RPTD) determined in phase I. Courses repeat every 3 weeks in the absence of disease progression or unacceptable toxicity. Tumor tissue samples from patients with small cell lung cancer may be collected at baseline for correlative studies. Tissue samples are analyzed for biomarkers and protein expression of Bcl-2, Bcl-Xl, MCL-1, Bax, Bad, c-Myc, L-Myc, and N-Myc by immunohistochemistry. After completion of study treatment, patients are followed for 30 days.