New antimalarial combination therapies with novel modes of action are required to counter the emergence and spread of drug resistance against existing therapeutics. Here, we present a study to evaluate the preventive activity of a combination of clinical antimalarial drug candidates, cabamiquine and ganaplacide, that have multistage activity against the liver and blood stages of infection. Cabamiquine (DDD107498, M5717) inhibits parasite protein synthesis, and ganaplacide (KAF156) inhibits protein trafficking, blocks the establishment of new permeation pathways, and causes endoplasmic reticulum expansion.
View Article and Find Full Text PDFA series of 5-aryl-2-amino-midazohiaiazole (ITD) derivatives were identified by a phenotype-based high-throughput screening using a blood stage () growth inhibition assay. A lead optimization program focused on improving antiplasmodium potency, selectivity against human kinases, and absorption, distribution, metabolism, excretion, and toxicity properties and extended pharmacological profiles culminated in the identification of (), which demonstrates potent cellular activity against 3D7 (EC = 0.006 μM) and achieves "artemisinin-like" kill kinetics with a parasite clearance time of <24 h.
View Article and Find Full Text PDFBackground: The novel anti-malarial cipargamin (KAE609) has potent, rapid activity against Plasmodium falciparum. Transient asymptomatic liver function test elevations were previously observed in cipargamin-treated subjects in two trials: one in malaria patients in Asia and one in volunteers with experimentally induced malaria. In this study, the hepatic safety of cipargamin given as single doses of 10 to 150 mg and 10 to 50 mg once daily for 3 days was assessed.
View Article and Find Full Text PDFBackground: KAF156 is a novel antimalarial drug that is active against both liver- and blood-stage Plasmodium parasites, including drug-resistant strains. Here, we investigated the causal prophylactic efficacy of KAF156 in a controlled human malaria infection (CHMI) model.
Methods: In part 1, healthy, malaria-naive participants received 800 mg KAF156 or placebo 3 hours before CHMI with P.
Background: KAF156 is a novel imidazolopiperazine anti-malarial with activity against pre-erythrocytic liver stages, asexual and sexual blood stages. Based on in vitro data, a two-way pharmacokinetic interaction was hypothesized for KAF156 use in combination with piperaquine (PPQ) as both drugs are CYP3A4 substrates and inhibitors. Potential combination effects on the QT interval were also assessed.
View Article and Find Full Text PDFThe artemether-lumefantrine combination requires food intake for the optimal absorption of lumefantrine. In an attempt to enhance the bioavailability of lumefantrine, new solid dispersion formulations (SDF) were developed, and the pharmacokinetics of two SDF variants were assessed in a randomized, open-label, sequential two-part study in healthy volunteers. In part 1, the relative bioavailability of the two SDF variants was compared with that of the conventional formulation after administration of a single dose of 480 mg under fasted conditions in three parallel cohorts.
View Article and Find Full Text PDFAntimicrob Agents Chemother
February 2017
The MIC of an antimalarial drug for a particular infection is the drug level associated with a net parasite multiplication rate of one per asexual cycle. To ensure the cure of malaria, the MIC must be exceeded until all parasites have been eliminated. The development of highly sensitive and accurate PCR quantitation of low-density malaria parasitemia enables the prospective pharmacokinetic-pharmacodynamic (PK-PD) characterization of antimalarial drug effects and now allows identification of the in vivo MIC.
View Article and Find Full Text PDFArtemether is co-administered with lumefantrine as part of a fixed-dose combination therapy for malaria in both adult and pediatric patients. However, artemether exposure is higher in younger infants (1-3 months) with a lower body weight (<5 kg) as compared to older infants (3-6 months) with a higher body weight (≥5 to <10 kg), children, and adults. In contrast, lumefantrine exposure is similar in all age groups.
View Article and Find Full Text PDFKAE609 [(1'R,3'S)-5,7'-dichloro-6'-fluoro-3'-methyl-2',3',4',9'-tetrahydrospiro[indoline-3,1'-pyridol[3,4-b]indol]-2-one] is a potent, fast-acting, schizonticidal agent in clinical development for the treatment of malaria. This study investigated the absorption, distribution, metabolism, and excretion of KAE609 after oral administration of [(14)C]KAE609 in healthy subjects. After oral administration to human subjects, KAE609 was the major radioactive component (approximately 76% of the total radioactivity in plasma); M23 was the major circulating oxidative metabolite (approximately 12% of the total radioactivity in plasma).
View Article and Find Full Text PDFKAE609 represents a new class of potent, fast-acting, schizonticidal antimalarials. This study investigated the safety and pharmacokinetics of KAE609 in combination with the long-acting antimalarial piperaquine (PPQ) in healthy volunteers. A two-way pharmacokinetic interaction was hypothesized for KAE609 and PPQ, as both drugs are CYP3A4 substrates and inhibitors.
View Article and Find Full Text PDFThis first-in-human randomized, double-blind, placebo-controlled, ascending-single and -multiple oral dose study was designed to evaluate the safety, tolerability, and pharmacokinetics in healthy volunteers of KAE609 (cipargamin; formerly NITD609), a spiroindolone now in trials for malaria treatment. It was studied in single-dose cohorts (1 to 300 mg, including one 30-mg food effect cohort) with 4 to 10 subjects in each cohort and in multiple-dose cohorts (10 to 150 mg once daily for 3 days) with 8 subjects in each cohort. The follow-up period was 6 to 8 days post-last dose.
View Article and Find Full Text PDFBackground: KAE609 (cipargamin; formerly NITD609, Novartis Institute for Tropical Diseases) is a new synthetic antimalarial spiroindolone analogue with potent, dose-dependent antimalarial activity against asexual and sexual stages of Plasmodium falciparum.
Methods: We conducted a phase 2, open-label study at three centers in Thailand to assess the antimalarial efficacy, safety, and adverse-event profile of KAE609, at a dose of 30 mg per day for 3 days, in two sequential cohorts of adults with uncomplicated P. vivax malaria (10 patients) or P.
Background: Artemether-lumefantrine (Coartem; AL) is a standard of care for malaria treatment as an oral six-dose regimen, given twice daily over three days with one to four tablets (20/120 mg) per dose, depending on patient body weight. In order to reduce the pill burden at each dose and potentially enhance compliance, two novel fixed-dose tablet formulations (80/480 mg and 60/360 mg) have been developed and tested in this study for bioequivalence with their respective number of standard tablets.
Methods: A randomized, open-label, two-period, single-dose, within formulation crossover bioequivalence study comparing artemether and lumefantrine exposure between the novel 80/480 mg tablet and four standard tablets, and the novel 60/360 mg tablet and three standard tablets, was conducted in 120 healthy subjects under fed conditions.
Polymersomes are one of the most interesting and versatile architectures among various self assembled systems for drug delivery. The stability and ability to load both hydrophilic and hydrophobic molecules make them excellent candidates to use as drug delivery systems. They demand for certain physicochemical parameters; especially hydrophilic to hydrophobic block ratio of copolymer to form vesicular morphologies.
View Article and Find Full Text PDFThis paper deals with in vivo evaluation of a new amphotericin-B-loaded polymersomes (PAMBO) formulation in terms of pharmacokinetics, toxicity, tissue distribution profile, and its efficacy in a murine model of disseminated candidiasis. Pharmacokinetic and tissue distribution studies of the PAMBO showed sustained levels of the drug in plasma as well as in target organs which harbor fungal and leishmanial infection. PAMBO was found to be much less toxic than Fungizone.
View Article and Find Full Text PDFAmphotericin B (AmB) is a broad spectrum antifungal and antileishmenial agent and its clinical use is limited due to substantial dose limiting toxicities such as nephrotoxicity. In this work, amphotericin B is formulated in polymersomes of branched (PEG)(3)-PLA co-polymer. Polymersomes were prepared by solvent injection method and the effects of various formulation and process parameters on size and size distribution were studied.
View Article and Find Full Text PDF(PEG)(3)-PLA copolymer has been explored for the formation of polymersomes. For this, three chains of methoxy-PEG(1100) were directly attached to citric acid by esterification. (Methoxy-PEG(1100))(3)-citrate was then reacted at its hydroxyl terminal with different moles of d,l-lactide by ring-opening polymerization to obtain polymers with five different PEG-to-PLA ratios ranging from 10:90 to 90:10.
View Article and Find Full Text PDFBackground: There is a continuing thrust to increase the efficacy and reduce the toxicity of existing and new drug molecules for their better usage to treat disease. Localized drug delivery has been explored in the same way, which can provide a platform to target local diseased tissues and can reduce the burden on the body by reducing the dose size and hence the dose-related toxicity of the molecules. Various polymers have evolved for the purpose of localized drug delivery, however, polyanhydrides are considered the best, supported by products in the clinical phases.
View Article and Find Full Text PDFHydrazinocurcumin (HZC) is a patented multiactivity compound and is a potent derivative of curcumin which is not yet explored for further development as formulation and requires the determination of biopharmaceutical suitability of the molecule. Intestinal permeability and logP of a compound are two vital biopharmaceutical properties by which, any "hit" molecule proceeds towards NCE (new chemical entity) and govern formulation design of bioactive molecules. In this report, a simple, precise and accurate isocratic reverse phase (RP) liquid chromatography method for simultaneous analysis of HZC and phenol red, for the application in rat in situ single-pass intestinal perfusion (SPIP) was developed and validated using FDA bioanalytical guidelines.
View Article and Find Full Text PDFLow molecular weight hydroxy fatty acid based polyanhydrides were synthesized by one pot method, a variable of typical melt-condensation and characterized by FTIR, NMR, DSC, and GPC. Polymer degrades by both surface and bulk erosion as trailed by weight loss, anhydride loss and surface morphology. Control over drug release was accessed with drugs featuring different aqueous solubility, that is, methotrexate (hydrophobic) and 5-fluorouracil (hydrophilic).
View Article and Find Full Text PDFPharmaceutical grade D,L-lactic acid, which is rather an economic source in comparison to lactide monomer, was utilized for synthesis of a series of copolymers with sebacic acid. Polymers were characterized by GPC, FTIR, NMR and DSC techniques, and formulated into blank and methotrexate (MTX) loaded microspheres by emulsion-solvent evaporation method. In vitro degradation of blank microspheres was studied by FTIR, GPC and SEM analysis.
View Article and Find Full Text PDFMany drugs that are administered in an unmodified form by conventional systemic routes fail to reach target organs in an effective concentration, or are not effective over a length of time due to a facile metabolism. Various types of targeting delivery systems and devices have been tried over a long period of time to overcome these problems. Targeted delivery or localized drug delivery offers an advantage of reduced body burden and systemic toxicity of the drugs, especially useful for highly toxic drugs like anticancer agents.
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