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1.
J Transl Med ; 17(1): 97, 2019 03 22.
Article in English | MEDLINE | ID: mdl-30902103

ABSTRACT

BACKGROUND: OZ439 is a new chemical entity which is active against drug-resistant malaria and shows potential as a single-dose cure. However, development of an oral formulation with desired exposure has proved problematic, as OZ439 is poorly soluble (BCS Class II drug). In order to be feasible for low and middle income countries (LMICs), any process to create or formulate such a therapeutic must be inexpensive at scale, and the resulting formulation must survive without refrigeration even in hot, humid climates. We here demonstrate the scalability and stability of a nanoparticle (NP) formulation of OZ439. Previously, we applied a combination of hydrophobic ion pairing and Flash NanoPrecipitation (FNP) to formulate OZ439 NPs 150 nm in diameter using the inexpensive stabilizer hydroxypropyl methylcellulose acetate succinate (HPMCAS). Lyophilization was used to process the NPs into a dry form, and the powder's in vitro solubilization was over tenfold higher than unprocessed OZ439. METHODS: In this study, we optimize our previous formulation using a large-scale multi-inlet vortex mixer (MIVM). Spray drying is a more scalable and less expensive operation than lyophilization and is, therefore, optimized to produce dry powders. The spray dried powders are then subjected to a series of accelerated aging stability trials at high temperature and humidity conditions. RESULTS: The spray dried OZ439 powder's dissolution kinetics are superior to those of lyophilized NPs. The powder's OZ439 solubilization profile remains constant after 1 month in uncapped vials in an oven at 50 °C and 75% RH, and for 6 months in capped vials at 40 °C and 75% RH. In fasted-state intestinal fluid, spray dried NPs achieved 80-85% OZ439 dissolution, to a concentration of 430 µg/mL, within 3 h. In fed-state intestinal fluid, 95-100% OZ439 dissolution is achieved within 1 h, to a concentration of 535 µg/mL. X-ray powder diffraction and differential scanning calorimetry profiles similarly remain constant over these periods. CONCLUSIONS: The combined nanofabrication and drying process described herein, which utilizes two continuous unit operations that can be operated at scale, is an important step toward an industrially-relevant method of formulating the antimalarial OZ439 into a single-dose oral form with good stability against humidity and temperature.


Subject(s)
Adamantane/analogs & derivatives , Malaria/drug therapy , Oral Sprays , Peroxides/administration & dosage , Powders , Adamantane/administration & dosage , Adamantane/pharmacokinetics , Administration, Oral , Chemistry, Pharmaceutical , Desiccation , Drug Stability , Freeze Drying , Humans , Nanoparticles/chemistry , Nebulizers and Vaporizers , Peroxides/pharmacokinetics , Solubility , Water/chemistry
2.
Cryobiology ; 68(3): 436-45, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24657198

ABSTRACT

Phenylketonuria (PKU) is an inherited metabolic disorder caused by deficient phenylalanine hydroxylase (PAH) activity, the enzyme responsible for the disposal of excess amounts of the essential amino acid phenylalanine (Phe). Phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) has potential to serve as an enzyme substitution therapy for this human genetic disease. Using 7-day-old Japanese Striped corn seedlings (Japonica Striped maize, Zea mays L. cv. japonica) that contain high activities of PAL, we investigated a number of methods to preserve the roots as an intact food and for long-term storage. The cryoprotectant effects of maple syrup and other edible sugars (mono- and oligosaccharides) were evaluated. Following thawing, the preserved roots were then examined to determine whether the rigid plant cell walls could protect the PAL enzyme from proteolysis during simulated (in vitro) digestion comprised of gastric and intestinal phases. While several treatments led to retention of PAL activity during freezing, upon thawing and in vitro digestion, root tissues that had been previously frozen in the presence of maple syrup exhibited the highest residual PAL activities (∼50% of the initial enzyme activity), in marked contrast to all of the treatments using other edible sugars. The structural integrity of the root cells, and the stability of the functional PAL tetramer were also preserved with the maple syrup protocol. These results have significance for the formulation of oral enzyme/protein therapeutics. When plant tissues are adequately preserved, the rigid cell walls constitute a protective barrier even under harsh (e.g. gastrointestinal-like) conditions.


Subject(s)
Cryopreservation/methods , Phenylalanine Ammonia-Lyase/metabolism , Seedlings/enzymology , Zea mays/enzymology , Cryoprotective Agents/metabolism , Enzyme Therapy , Humans , Phenylalanine Ammonia-Lyase/administration & dosage , Phenylalanine Ammonia-Lyase/therapeutic use , Phenylketonurias/drug therapy , Seedlings/physiology , Zea mays/physiology
3.
J Nutr Sci ; 12: e15, 2023.
Article in English | MEDLINE | ID: mdl-36843963

ABSTRACT

Lost from follow-up, after starting moderate acute malnutrition (MAM) is an ongoing challenge of public health until the admitted children reached the standard weight of a reference child. Thus, the present study aimed to assess the rate and estimated time to attrition after under-five children started treatment for MAM in the Gubalafto district. A facility-based retrospective cohort study was employed among 487 participant children who had been managed targeted therapeutic feeding from 1 June 2018 to 1 May 2021. The overall mean (±sd) age of the participants' children was 22⋅1 (±12⋅6) months. At the end of the study period, 55 (11⋅46 %) under-five children developed attrition from the treatment after starting ready use of therapeutic feeding. After checking all assumptions, a multivariable Cox regression model was used to claim independent predictors for time to attritions. The median time of attrition after starting treatment of MAM was 13 (IQR ±9) weeks, with the overall incidence of attrition rate reported at 6⋅75 children Per Week (95 % CI 5⋅56, 9⋅6). In the final model of multivariable Cox regression, the hazard of attrition was significantly higher for children from rural residence (AHR 1⋅61; 95 % CI 1⋅18, 2⋅18; P = 0⋅001), and caregivers with their dyads did not get nutritional counselling at baseline (AHR 2⋅78; 95 % CI 1⋅34, 5⋅78; P = 0⋅001). The findings of the present study showed that nearly one in every eleven under-five children was attrition (lost to follow-up) in a median time of 13 (IQR ±9) weeks. We strongly recommended for caregivers provisions of diversification of daily nutrition supplementation of their dyads.


Subject(s)
Malnutrition , Humans , Child , Infant , Retrospective Studies , Ethiopia/epidemiology , Follow-Up Studies , Malnutrition/epidemiology , Risk Factors
4.
Biomed Pharmacother ; 153: 113466, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36076576

ABSTRACT

Novel oral therapeutic agents based on inhibition or binding activity without adverse events in CKD patients are urgently needed. Here, 5/6 nephrectomy (NX) rats were used to construct a CKD model. Aminated cellulose (AC711), which is metal-free, non-absorbable, and low-volume expansive, was used as a novel oral therapeutic agent for hyperphosphataemia treatment in rats. The efficacy of AC711 on serum and urinary phosphate levels, the expression of type II sodium-dependent phosphate cotransporter (NPT2b), and type III Na-dependent phosphate cotransporter (PiT-1/2) was examined. Serum fibroblast growth factor-23 (FGF-23) levels, parathyroid hormone (PTH) levels, and the phenotypic transformation of vascular smooth muscle cell markers (smooth muscle 22 (SM22) and Runx2) are considered an adaptive response to elevated serum phosphate levels. A similar efficacy of AC711 was observed on serum and urinary phosphate levels when the same dose of AC711 and sevelamer was administered to 5/6 NX rats. The decreasing expression of NPT2b, PiT-1, and PiT-2 was examined in the AC711 groups in a dose-dependent manner. The sevelamer and AC711-MD groups for FGF-23 and PTH indicated no significant difference. The down-regulation of Runx2 expression and up-regulation of SM22 expression were seen in the AC711 groups in a dose-dependent manner. Two suppression mechanisms (binding and inhibiting activities) were observed in the gastrointestinal (GI) tract in the AC711 groups. A novel oral phosphate binder, AC711, showed both binding and inhibition characteristics. The low-volume expansion of AC711 following exposure to simulated intestinal fluid provides the potential therapeutic benefits with the advantage of moderate GI side effects.


Subject(s)
Cellulose , Hyperphosphatemia , Renal Insufficiency, Chronic , Animals , Cellulose/analogs & derivatives , Cellulose/pharmacology , Core Binding Factor Alpha 1 Subunit/metabolism , Disease Models, Animal , Fibroblast Growth Factors/metabolism , Hyperphosphatemia/drug therapy , Parathyroid Hormone , Phosphates/metabolism , Rats , Renal Insufficiency, Chronic/drug therapy , Sevelamer
5.
ACS Infect Dis ; 4(6): 970-979, 2018 06 08.
Article in English | MEDLINE | ID: mdl-29575888

ABSTRACT

Malaria poses a major burden on human health and is becoming increasingly difficult to treat due to the development of antimalarial drug resistance. The resistance issue is further exacerbated by a lack of patient adherence to multi-day dosing regimens. This situation motivates the development of new antimalarial treatments that are less susceptible to the development of resistance. We have applied Flash NanoPrecipitation (FNP), a polymer-directed self-assembly process, to form stable, water-dispersible nanoparticles (NPs) of 50-400 nm in size containing OZ439, a poorly orally bioavailable but promising candidate for single-dose malaria treatment developed by Medicines for Malaria Venture (MMV). During the FNP process, a hydrophobic OZ439 oleate ion paired complex was formed and was encapsulated into NPs. Lyophilization conditions for the NP suspension were optimized to produce a dry powder. The in vitro release rates of OZ439 encapsulated in this powder were determined in biorelevant media and compared with the release rates of the unencapsulated drug. The OZ439 NPs exhibit a sustained release profile and several-fold higher release concentrations compared to that of the unencapsulated drug. In addition, XRD suggests the drug was stabilized into an amorphous form within the NPs, which may explain the improvement in dissolution kinetics. Formulating OZ439 into NPs in this way may be an important step toward developing a single-dose oral malaria therapeutic, and offers the possibility of reducing the amount of drug required per patient, lowering delivery costs, and improving dosing compliance.


Subject(s)
Adamantane/analogs & derivatives , Antimalarials/administration & dosage , Drug Compounding , Nanoparticles/chemistry , Peroxides/administration & dosage , Adamantane/administration & dosage , Adamantane/chemistry , Adamantane/pharmacokinetics , Antimalarials/chemistry , Antimalarials/pharmacokinetics , Drug Delivery Systems , Drug Liberation , Humans , Hydrophobic and Hydrophilic Interactions , Ions/chemistry , Molecular Structure , Peroxides/chemistry , Peroxides/pharmacokinetics
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