Sensitive and cost-effective LC-MS/MS method for quantitation of CVT-6883 in human urine using sodium dodecylbenzenesulfonate additive to eliminate adsorptive losses

CVT-6883, a novel selective A(2B) adenosine receptor antagonist currently under clinical development, is highly lipophilic and exhibits high affinity for non-specific binding to container surfaces, resulting in very low recovery in urine assays. Our study showed the use of sodium dodecylbenzenesulfonate (SDBS). a low-cost additive, eliminated non-specific binding problems in the analysis of CVT-6883 in human urine without compromising sensitivity. A new sensitive and selective LC-MS/MS method for quantitation of CVT-6883 in the range of 0.200-80.0 ng/mL using SDBS additive was therefore developed and validated for the analysis of human urine samples. The recoveries during sample collection, handling and extraction for the analyte and internal standard (d(5)-CVT-6883) were higher than 87%. CVT-6883 was found stable under the following conditions: in extract - at ambient temperature for 3 days, under refrigeration (5 degrees C) for 6 days: in human urine (containing 4 mM SDBS) - after three freeze/thaw cycles, at ambient temperature for 26 h, under refrigeration (5 degrees C) for 94 h, and in a freezer set to -20 degrees C for at least 2 months. The results demonstrated that the validated method is sufficiently sensitive, specific, and cost-effective for the analysis of CVT-6883 in human urine and will provide a powerful tool to support the clinical programs for CVT-6883. (C) 2009 Elsevier B.V. All rights reserved.