Genotoxicity evaluation of a valsartan-related complex N-nitroso-impurity.

Recently, the formation of genotoxic and carcinogenic N-nitrosamines impurities during drug manufacturing of tetrazole-containing angiotensin-II blockers has been described. However, drug-related (complex) nitrosamines may also be generated under certain conditions, i.e., through nitrosation of vulnerable amines in drug substances in the presence of nitrite. An investigation of valsartan drug substance showed that a complex API-related N-nitrosamine chemically designated as (S)-2-(((2'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-4-yl)methyl)(nitroso)amino)-3-methylbutanoic acid (named 181-14) may be generated. 181-14 was shown to be devoid of a mutagenic potential in the Non-GLP Ames test. According to ICH M7 (R1) (2018), impurities that are not mutagenic in the Ames test would be considered Class 5 impurities and limited according to ICH Q3A (R2) and B (R2) (2006) guidelines. However, certain regulatory authorities raised the concern that the Ames test may not be sufficiently sensitive to detect a mutagenic potential of nitrosamines and requested a confirmatory in vivo study using a transgenic animal genotoxicity model. Our data show that 181-14 was not mutagenic in the transgenic gene mutation assay in MutaTMMice. The data support the conclusion that the Ames test is an adequate and sensitive test system to assess a mutagenic potential of nitrosamines.

Physiologically Based Biopharmaceutics Model of Vildagliptin Modified Release (MR) Tablets to Predict In Vivo Performance and Establish Clinically Relevant Dissolution Specifications.

The objective of the study was to predict pharmacokinetic (PK) and pharmacodynamic (PD) parameters of matrix-based modified release (MR) drug product of vildagliptin. Physiologically based biopharmaceutics modeling (PBBM) was developed using GastroPlus™ based on the available data including immediate-release (IR) drug product of vildagliptin. In vitro-in vivo correlation (IVIVC) was developed using mechanistic deconvolution to predict plasma concentration-time profile and PK parameters for a MR drug product planned for clinical use. Both methods, i.e., PBBM and IVIVC, were compared for the predicted PK parameters. Integration of DDDPlus™ and GastroPlus™ modeling was performed to explore clinically relevant dissolution specifications for vildagliptin MR tablets. The bioequivalence (BE) between batches with different dissolution specifications was evaluated using virtual clinical trials. The PD effect of dipeptidyl peptidase-IV (DPP-IV) inhibition was simulated utilizing PDPlus™ model in GastroPlus™. The results indicated that IVIVC best correlated the simulated PK parameters with those observed with the clinical study. The outcomes highlight the importance of integration of in vitro and in silico tools towards predictability of PK and PD parameters for a MR drug product. However, the post absorptive phase was found to be more dependent on the demographics of the healthy subjects.

Evaluation of Clinical Drug Interaction Potential of Clofazimine Using Static and Dynamic Modeling Approaches.

The 2016 World Health Organization treatment recommendations for drug-resistant tuberculosis (DR-TB) positioned clofazimine as a core second-line drug. Being identified as a cytochrome P450 (P450) inhibitor in vitro, a P450-mediated drug interaction may be likely when clofazimine is coadministered with substrates of these enzymes. The P450-mediated drug interaction potential of clofazimine was evaluated using both static [estimation of the R1 and area under the plasma concentration-time curve ratio (AUCR) values] and dynamic [physiologically based pharmacokinetics (PBPK)] modeling approaches. For static and dynamic predictions, midazolam, repaglinide, and desipramine were used as probe substrates for CYP3A4/5, CYP2C8, and CYP2D6, respectively. The AUCR static model estimations for clofazimine with the substrates midazolam, repaglinide, and desipramine were 5.59, 1.34, and 1.69, respectively. The fold increases in the area under the curve (AUC) predicted for midazolam, repaglinide, and desipramine with clofazimine (based on PBPK modeling) were 2.69, 1.60, and 1.47, respectively. Clofazimine was predicted to be a moderate-to-strong CYP3A4/5 inhibitor and weak CYP2C8 and CYP2D6 inhibitor based on the calculated AUCR by static and PBPK modeling. Additionally, for selected antiretroviral, antitubercular, antihypertensive, antidiabetic, antileprotics, and antihyperlipidemic CYP3A4/5 substrate drugs, approximately 2- to 6-fold increases in the AUC were predicted with static modeling when coadministered with 100 mg of clofazimine. Therefore, the possibility of an increase in the AUC of CYP3A4/5 substrates when coadministered with clofazimine cannot be ignored.

P7170, a novel inhibitor of mTORC1/mTORC2 and Activin receptor-like Kinase 1 (ALK1) inhibits the growth of non small cell lung cancer.

BACKGROUND: Lung cancer is the major cause of cancer-related deaths and many cases of Non Small Cell Lung Cancer (NSCLC), a common type of lung cancer, have frequent genetic/oncogenic activation of EGFR, KRAS, PIK3CA, BRAF, and others that drive tumor growth. Some patients though initially respond, but later develop resistance to erlotinib/gefitinib with no option except for cytotoxic therapy. Therefore, development of novel targeted therapeutics is imperative to provide improved survival benefit for NSCLC patients. The mTOR cell survival pathway is activated in naïve, or in response to targeted therapies in NSCLC. METHODS: We have discovered P7170, a small molecule inhibitor of mTORC1/mTORC2/ALK1 and investigated its antitumor efficacy using various in vitro and in vivo models of human NSCLC. RESULTS: P7170 inhibited the phosphorylation of AKT, S6 and 4EBP1 (substrates for mTORC2 and mTORC1) levels by 80-100% and growth of NSCLC cells. P7170 inhibited anchorage-independent colony formation of NSCLC patient tumor-derived cells subsistent of disease sub-types. The compound also induced apoptosis in NSCLC cell lines. P7170 at a well-tolerated daily dose of 20 mg/kg significantly inhibited the growth of NSCLC xenografts independent of different mutations (EGFR, KRAS, or PIK3CA) or sensitivity to erlotinib. Pharmacokinetic-pharmacodynamic (PK-PD) analysis showed sub-micro molar tumor concentrations along with mTORC1/C2 inhibition. CONCLUSIONS: Our results provide evidence of antitumor activity of P7170 in the erlotinib -sensitive and -insensitive models of NSCLC.

Bioequivalence Between a New Omalizumab Prefilled Syringe With an Autoinjector or with a Needle Safety Device Compared with the Current Prefilled Syringe: A Randomized Controlled Trial in Healthy Volunteers.

Omalizumab is an anti-IgE monoclonal antibody currently approved for the treatment of asthma, nasal polyps/chronic rhinosinusitis with nasal polyps, and chronic spontaneous urticaria. Omalizumab is available as an injection in a prefilled syringe (PFS) with a needle safety device (NSD). New product configurations were developed to reduce the number of injections per dose administration, improve patient convenience and treatment compliance. The objective of this randomized open-label 12-week study was to demonstrate pharmacokinetic bioequivalence between (1) new PFS with autoinjector (PFS-AI), (2) new PFS-NSD configuration, and (3) current PFS-NSD configuration. Each new configuration was considered bioequivalent to the current configuration if the confidence intervals (CIs) for the geometric mean ratios (GMR) were contained in the 0.80-1.25 range for maximum concentration (Cmax), area under the concentration-time curve until the last quantifiable measurement (AUClast), and AUC extrapolated to infinity (AUCinf). Safety was assessed throughout the study. In total, 193 healthy volunteers were randomized at 1:1:1 ratio to omalizumab 1×300 mg/2 mL via new PFS-AI (n = 66), omalizumab 1×300 mg/2 mL via new PFS-NSD (n = 64), or omalizumab 2×150 mg/1 mL via current PFS-NSD (n = 63). Comparing new PFS-AI versus current PFS-NSD, the GMRs were: Cmax, 1.085; AUClast, 1.093; AUCinf, 1.100. Comparing new PFS-NSD versus current PFS-NSD, the GMRs were: Cmax, 1.006; AUClast, 1.016; AUCinf, 1.027. The 95% CIs for all GMR parameters were contained within the 0.80-1.25 range. Safety findings were consistent with the known safety profile of omalizumab. Single-dose omalizumab administered as the new PFS-AI or new PFS-NSD was bioequivalent to the current PFS-NSD.

Pharmacokinetics of Ganaplacide and Lumefantrine in Adults, Adolescents, and Children with Plasmodium falciparum Malaria Treated with Ganaplacide Plus Lumefantrine Solid Dispersion Formulation: Analysis of Data from a Multinational Phase 2 Study.

The novel antimalarial ganaplacide combined with lumefantrine solid dispersion formulation (LUM-SDF) was effective and well tolerated in the treatment of uncomplicated falciparum malaria in adults, adolescents, and children in a multinational, prospective, randomized, active-controlled Phase II study conducted between August 2017 and June 2021 (EudraCT 2020-003284-25, Clinicaltrials.gov NCT03167242). Pharmacokinetic data from that study are reported here. The trial comprised three parts: a run-in part in 12 adult/adolescent patients treated with a single dose of ganaplacide 200 mg plus LUM-SDF 960 mg assessed potential pharmacokinetic (PK) interactions between ganaplacide and lumefantrine; in Part A, adult/adolescent patients received one of the six ganaplacide-LUM-SDF regimens or artemether-lumefantrine; and in Part B, three dose regimens identified in Part A, and artemether-lumefantrine, were assessed in children aged 2 to <12 years, with body weight ≥10 kg. A rich blood sampling schedule was used for all 12 patients in the PK run-in part and a subset of patients (N = 32) in Part A, with sparse sampling for remaining patients in Parts A (N = 275) and B (N = 159). Drug concentrations were determined by a validated protein precipitation and reverse phase liquid chromatography with tandem mass spectrometry detection method. Parameters including AUCinf, AUClast, AUC0-t, Cmax, and tmax were reported where possible, using non-compartmental analysis. In the PK run-in part, there was no notable increase in ganaplacide or lumefantrine exposure when co-administered. In Parts A and B, ganaplacide exposures increased with dose, but lumefantrine exposure was numerically under dose-proportional. Lumefantrine exposure was higher with ganaplacide-LUM-SDF than with artemether-lumefantrine, although high variability was observed. Ganaplacide and lumefantrine exposures (Cmax and AUC0-24 h) were comparable across age and body weight groups. Drug exposures needed for efficacy were achieved using the dose regimen 400 mg ganaplacide plus lumefantrine 960 mg once daily for 3 days under fasted conditions.

Discovery of benzo[d]imidazo[5,1-b]thiazole as a new class of phosphodiesterase 10A inhibitors.

The design, synthesis and structure activity relationship studies of a series of compounds from benzo[d]imidazo[5,1-b]thiazole scaffold as phosphodiesterase 10A (PDE10A) inhibitors are discussed. Several potent analogs with heteroaromatic substitutions (9a-d) were identified. The anticipated binding mode of these analogs was confirmed by performing the in silico docking experiments. Later, the heteroaromatics were substituted with saturated heteroalkyl groups which provided a tool compound 9e with excellent PDE10A activity, PDE selectivity, CNS penetrability and with favorable pharmacokinetic profile in rats. Furthermore, the compound 9e was shown to be efficacious in the MK-801 induced psychosis model and in the CAR model of psychosis.

Isothiazole and isoxazole fused pyrimidones as PDE7 inhibitors: SAR and pharmacokinetic evaluation.

The synthesis and structure-activity relationship studies of isothiazole and isoxazole fused pyrimidones as PDE7 inhibitors are discussed. The pharmacokinetic profile of 10 and 21 with adequate CNS penetration, required for in vivo Parkinson's disease models, are disclosed.

Imidazopyridazinones as novel PDE7 inhibitors: SAR and in vivo studies in Parkinson's disease model.

The synthesis and structure-activity relationship studies of a series of compounds from imidazopyridazinone scaffold as PDE7 inhibitors are disclosed. Potent analogs such as compounds 7 (31nM), 8 (27nM), and 9 (12nM) were identified. The PDE selectivity and pharmacokinetic profile of compounds 7, 8 and 9 are also disclosed. The adequate CNS penetration of compound 7 in mice allowed it to be tested in the MPTP induced PD model and haloperidol induced catalepsy model to probe the differential pharmacology of PDE7 in the striatal pathway.

Development, validation and application of a liquid chromatography-tandem mass spectrometry method for the activity and inhibition of DPP-4.

Background: Inhibition of the enzyme dipeptidyl peptidase 4 (DPP-4) is a pharmaceutical treatment for type 2 diabetes. To demonstrate bioequivalence of enzyme inhibition of a new dosage form of the inhibitor vildagliptin, a method for enzyme activity was developed, validated and applied using liquid chromatography and tandem mass spectrometry (LC-MS/MS). Results: The method was validated fit for purpose, including accuracy, precision as well as the stability of the activity and the inhibition of DPP-4 in human plasma. Conclusion: A method for the determination of the activity and inhibition of DPP-4 was developed using LC-MS/MS readout; the characteristics and performance of the method met predefined acceptance criteria and were fit for the purpose of a bioequivalence clinical trial.

The Bioequivalence Between Valsartan Oral Solution and Suspension Formulations Developed for Pediatric Use.

The bioequivalence of valsartan 160 mg oral solution compared to suspension was assessed in a single-dose, open-label, randomized, 2-period, 2-way crossover study in 82 healthy adults. The participants were randomly assigned (1:1) to receive a single dose of the solution or suspension formulation in each of the two treatment periods. Serial blood samples for pharmacokinetic evaluation were collected up to 48 hours post-dose. The pharmacokinetic parameters were estimated by noncompartmental methods and analyzed as per bioequivalence criteria of statistical analysis. The peak plasma concentration of valsartan was reached with median time of 1 and 3 hours with solution and suspension formulation, respectively. Compared to suspension formulation, the mean peak plasma concentration with solution formulation was higher by 32% (90%CI, 1.27-1.38) while the geometric mean ratios (1.09) and the associated 90%CIs (1.05-1.13) of both the areas under the concentration time-curves (from time zero to the last quantifiable concentration and from time zero to infinity) were contained in the required range of 0.80 to 1.25. No new safety signals were observed with either of the formulations.

Therapeutic equivalence of vildagliptin 100 mg once daily modified release to 50 mg twice daily immediate release formulation: An open-label, randomized, two-period, single- and multiple-dose, 6-day crossover study.

BACKGROUND AND AIMS: Vildagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor to treat type 2 diabetes mellitus, is available as immediate release (IR) tablets administered at 50 mg twice daily (BID). A 100 mg modified release (MR) formulation was developed for once daily (QD) dosing. This study aimed to compare the therapeutic equivalence of vildagliptin 100 mg MR QD (test) and 50 mg IR BID (reference) formulations at steady state under fasting conditions. METHODS: This was an open-label, randomized, two-period, single- and multiple-dose, two-way crossover, steady state study conducted in healthy adult subjects. Both vildagliptin formulations were administered for six days. Endpoints included pharmacodynamic equivalence, pharmacokinetic parameters, and tolerability of both formulations. RESULTS: Thirty subjects were enrolled and 26 completed both treatments. Maximum plasma concentration and exposure achieved with test was lower than reference formulation on day 1 and 6. The DPP-4 enzyme inhibition over time (DPP-4-AUEC0-24) was comparable between the formulations. Both formulations were well tolerated. CONCLUSION: This study confirms the therapeutic equivalence of vildagliptin IR and MR formulations for DPP-4 enzyme inhibition over time. The study supports vildagliptin 100 mg MR QD as a useful therapeutic alternative to 50 mg IR BID formulation to possibly improve treatment adherence and patient compliance. Long-term safety of the vildagliptin 100 mg MR QD formulation is not evaluated in this study.