Development of a New Non-radioactive Test for Measuring Glomerular Filtration Rate Using the Tetrapeptide N-acetyl-Ser-Asp-Lys-Pro-amide (AcSDKP-NH2) (AcSDKP-NH2)

Development of a New Non-radioactive Test for Measuring Glomerular Filtration Rate Using the Tetrapeptide N-acetyl-Ser-Asp-Lys-Pro-amide (AcSDKP-NH2)

Development of a New Non-radioactive Test for Measuring Glomerular Filtration Rate Using the Tetrapeptide N-acetyl-Ser-Asp-Lys-Pro-amide (AcSDKP-NH2)

The purpose of the study is to validate a new reference marker for evaluation of renal function (glomerular filtration rate).

Chronic kidney disease (CKD) is a worldwide public health problem with an increasing incidence and prevalence, poor outcomes (kidney failure, complications of decreased kidney function and cardiovascular disease), and high cost. Some of the adverse outcomes can be prevented or delayed by early detection and treatment. However, CKD is frequently underdiagnosed and undertreated. The glomerular filtration rate (GFR) is considered as the best index of renal function. The clinical action plan promoted by International Guidelines groups refers to GFR values. Despite recent improvements, prediction equations developed in order to estimate GFR elicit a huge lack of accuracy when considering the individual patient, especially in case of early CKD. Rigorous assessment of GFR requires the measurement of urinary or plasma clearance of an ideal exogenous filtration marker which is either non-radioactive (inulin, iothalamate, or iohexol) or radioactive ( 51Cr-EDTA or 99mTc DTPA. Measuring clearance with the use of exogenous markers is difficult to perform in clinical practice because it is expensive and cumbersome and needs specialised laboratories and thus, is underused. There is an unmet need for the development of a new non-radioactive GFR tracer that could combine both the analytical accuracy of radioactive tracers and the simplicity of its measurement. Such a tracer should improve clinical care and follow-up of patients.

Chronic kidney disease, GFR, Inulin, 51Cr-EDTA, ASDKP-NH2, Healthy male 18-35 yrs old, non smokers, non allergic, Or Male/female 18-80 yrs old with chronic Kidney disease

NAcSDKP clearance for GFR measurement is compared to inuline and 51Cr-EDTA clearance in two phase I studies in 50 healthy subjects. GFR is first assessed at equilibrium by measuring urinary clearances of inuline and NAcSDKP continuously co-infused after a loading dose; and second by plasma clearances of 51Cr-EDTA and NAcSDKP after a single IV bolus. Optimal conditions for using NAcSDKP as a marker for GFR and the tolerability of the peptide are assessed during these studies. Then, a phase IIa study will be performed to compare the 2 methods in 45 patients with various degrees of renal failure.

Inclusion Criteria: Phase I: 18-35 years male Phase I: healthy volunteers Phase II: 18-80 years patients (both sex) Phase II: with Chronic Kidney Disease Exclusion Criteria: Phase I: Smokers Phase I: Allergic

Université Paris-Descartes, Faculté de Médecine; Assistance Publique Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Centre d'Investigations Cliniques; INSERM, CIC 9201, F-75015 Paris, France

Mesmin C, Cholet S, Blanchard A, Chambon Y, Azizi M, Ezan E. Mass spectrometric quantification of AcSDKP-NH2 in human plasma and urine and comparison with an immunoassay. Rapid Commun Mass Spectrom. 2012 Jan 30;26(2):163-72. doi: 10.1002/rcm.5326.