Ranjit C. Desai

Discovery of a Potent and Orally Efficacious TGR5 Receptor Agonist

TGR5 is a G protein-coupled receptor (GPCR), activation of which promotes secretion of glucagon-like peptide-1 (GLP-1) and modulates insulin secretion. The 2-thio-imidazole derivative 6g was identified as a novel, potent, and selective TGR5 agonist (hTGR5 EC50 = 57 pM, mTGR5 = 62 pM) with a favorable pharmacokinetic profile. The compound 6g was found to have potent glucose lowering effects in vivo during an oral glucose tolerance test in DIO C57 mice with ED50 of 7.9 mg/kg and ED90 of 29.2 mg/kg.

Pharmacological Characterization of ZYAN1, a Novel Prolyl Hydroxylase Inhibitor for the Treatment of Anemia

Prolyl hydroxylase (PHD) inhibitors stabilize hypoxia inducible factor (HIF), and exert antianemic effect by potentiating erythropoietin (EPO) expression and down-regulation of hepcidin. ZYAN1 is a novel PHD inhibitor under clinical development for the treatment of anemia. The pharmacodynamic effects of acute and chronic dosing of ZYAN1 were assessed in normal and 5/6 nephrectomized Wistar rats. The effect of ZYAN1 was also investigated in cisplatin-induced anemia using C57 mice. Acute treatment with ZYAN1 increased circulating EPO levels (10.3 ± 3.7 and 40.0 ± 8.5 fold rise at 15 and 30 mg/kg, respectively), reticulocyte count (4.2 ± 0.5 and 6.0 ± 0.2 fold rise at 15 and 30 mg/kg, respectively) and stabilized HIF (28% increase at 45 mg/kg) in normal rats. Nephrectomized rats showed similar dose-related pharmacodynamic effects. In a 28-day study in nephrectomized rats, ZYAN1 administered every alternate day, caused increase in hemoglobin (1.9 ± 0.3 and 2.5 ± 0.4 g/dL) and RBC count (10.7 ± 4.0 and 14.0 ± 4.1%) at 15 and 30 mg/kg respectively. In cisplatin-treated mice also an increase in hemoglobin (3.4 ± 0.2 and 5.9 ± 0.2 g/dL) and RBC count (22.5 ± 2.2 and 37.3 ± 1.7%) at 15 and 30 mg/kg respectively was observed. ZYAN1s effects on hemoglobin and RBC count were distinct from darbepoietin. ZYAN1 demonstrated hematinic potential by combined effects on EPO release and efficient iron utilization. The efficacy of ZYAN1 in disease models of different etiologies suggests that it will be useful in treating wide spectrum of anemia patients.

Influence of acute and chronic kidney failure in rats on the disposition and pharmacokinetics of ZYAN1, a novel prolyl hydroxylase inhibitor, for the treatment of chronic kidney disease-induced anemia

Abstract 1. ZYAN1 is a prolyl hydroxylase inhibitor in clinical development for treatment of anemia associated with chronic kidney disease (CKD). We evaluated the effect of acute and chronic kidney impairment on the pharmacokinetics of ZYAN1 in rat models. 2. Cisplatin (2.5, 5 and 7.5 mg/kg) was used to induce acute kidney injury (AKI), and five-sixth and total nephrectomy was used to induce chronic kidney injury (CKI) in male Wistar rats. All groups received a single 15 mg/kg oral dose of ZYAN1. Blood/urine samples were analyzed for ZYAN1 to assess peak concentration (Cmax), area under the concentration–time curve (AUCinf), total body clearance (CL/F) and elimination half-life (T1/2). 3. Cmax and AUCinf were not significantly different in the various AKI groups or in five-sixth nephrectomized rats, as compared to control rats. Recovery of ZYAN1 in urine was reduced; the impact on the CL/F was minimal. There was a 2-fold increase in AUCinf with reduction in CL/F in total nephrectomized rats. T1/2 was longer for ZYAN1 in the severe AKI/five-sixth nephrectomy rats and total nephrectomy rats as compared to control rats. 4. Based on the rodent data it may be inferred that PK of ZYAN1 in CKD patients may be minimally affected.

Pharmacological characterization of ZYDPLA1, a novel long-acting dipeptidyl peptidase-4 inhibitor.

Dipeptidyl peptidase‐4 (DPP‐4) is responsible for degradation of glucagon‐like peptide 1 (GLP‐1) and gastric inhibitory polypeptide (GIP), the endogenous incretins that stimulate glucose‐dependent insulin secretion. The objective was to evaluate preclinical profile of a novel DPP‐4 inhibitor ZYDPLA1.

ZY15557, a novel, long acting inhibitor of dipeptidyl peptidase‐4, for the treatment of Type 2 diabetes mellitus

Dipeptidyl peptidase (DPP)‐4 inhibitors increase levels of glucagon‐like peptide‐1 (GLP‐1) and provide clinical benefit in the treatment of type 2 diabetes mellitus. As longer acting inhibitors have therapeutic advantages, we developed a novel DPP‐4 inhibitor, ZY15557, that has a sustained action and long half‐life.

ZY15557, a novel, long acting DPP‐4 inhibitor for the treatment of type 2 diabetes mellitus

Dipeptidyl peptidase (DPP)‐4 inhibitors increase levels of glucagon‐like peptide‐1 (GLP‐1) and provide clinical benefit in the treatment of type 2 diabetes mellitus. As longer acting inhibitors have therapeutic advantages, we developed a novel DPP‐4 inhibitor, ZY15557, that has a sustained action and long half‐life.

Is the Inhibition of Dipeptidyl Peptidase-4 (DDP-4) Enzyme Route Dependent and/or Driven by High Peak Concentration?– Seeking Answers with ZYDPLA1, a Novel Long Acting DPP-4 Inhibitor, in a Rodent Model

ZYDPLA1 is a long acting enzyme dipeptidyl peptidase-4 (DPP-4) inhibitor. The comparative effect of DPP-4 inhibition after intravenous (IV) and oral administration of ZYDPLA1 in a rat model was evaluated to answer the question of route dependency and/or the need of high plasma levels of ZYDPLA1. The study was conducted using parallel design in male Wistar rats for IV/oral route (n=9 and 6, for IV and oral respectively). A single 30 mg/kg dose of ZYDPLA1 was administered. Plasma samples were analysed for ZYDPLA1 concentration and DPP-4 inhibition. Pharmacokinetic analysis was carried out to assess peak concentration, area under the concentration-time curve, total body clearance, elimination half-life, and mean residence time. The PK/PD correlation was performed using standard sigmoidal Emax modelling to derive; maximum effect (Emax) and concentration to exert 50% Emax effect (EC50). ZYDPLA1 showed rapid absorption, high volume of distribution, low clearance, and complete oral bioavailability. The Emax derived after both routes and corresponding PK/PD profile showed comparable DDP-4 inhibition. The EC50 for IV (0.021 µg/mL) was comparable to the oral route (0.019 µg/mL). ZYDPLA1 showed full DPP-4 inhibition without regard to the route of administration. Higher systemic peak levels showed no bearing on the DDP-4 inhibition.

Sensitive and specific LC-ESI-MS/MS method for determination of ZYDPLA1, a novel long-acting dipeptidyl peptidase 4 inhibitor in rat plasma: An application for toxicokinetic study in rats

A rapid and highly specific assay was developed and validated for the estimation of ZYDPLA1 in rat plasma using liquid chromatography coupled to tandem mass spectrometry with positive electrospray ionization. Method validation comprised of parameters such as specificity, matrix effect, precision, accuracy, recovery, stability, etc. The assay procedure involved a simple protein precipitation of ZYDPLA1 and alprazolam (internal standard) from rat plasma using acetonitrile. Chromatographic separation was achieved with a gradient mobile phase comprising: (A) 0.2% ammonia in purified water; (B) 0.1% formic acid in isopropyl alcohol/methanol (1: 1 v/v); and (C) acetonitrile at a flow rate of 1 mL/min on an ACE-5, C18 (4.6 × 50 mm) column with a run time of 5.5 min. The quantitation of ZYDPLA1 was achieved by the summation of four multiple reaction mode transitions (m/z 399.7 → 383.0, 399.7 → 276.10, 399.7 → 153.20 and 399.7 → 127.20), while that of the internal standard was by a single multiple reaction mode transition (m/z 309.10 → 281.00). The lower limit of quantitation achieved was 0.01 μg/mL and the method showed linearity from 0.01 to 25 μg/mL. The intra- and inter-day precision (%CV) of the quality control samples was within 8.81% and accuracy was ±10% of nominal values. This novel method was applied for evaluation of toxicokinetics of ZYDLA1 in rats.

A sensitive assay for ZYAN1 in human whole blood and urine utilizing positive LC–MS/MS electrospray ionization

AIM A sensitive LC-MS/MS method was developed and validated for estimation of ZYAN1 in human blood/urine. METHODS An analog internal standard IOX2 along with ZYAN1 was quantified using selective reaction monitoring in positive mode. The chromatographic separation was performed by gradient elution with C18 analytical column (3 µm, 50 mm × 2.0 mm) with 4-min run time using an acidified mobile phase consisting of ammonium formate and acetonitrile. Protein precipitation enabled extraction of analytes from diluted blood/urine. RESULTS Calibration curve of ZYAN1 was linear (2-5000 ng/ml). The recovery of ZYAN1 and IOX2 was between 87 and 104%. Interday and intraday accuracy and precision was found well within the acceptance criteria. CONCLUSION The validated assay was applied for clinical pharmacokinetics of ZYAN1 in healthy volunteers.