scholarly journals Development and pharmacokinetic evaluation of osmotically controlled drug delivery system of Valganciclovir HCl for potential application in treatment of CMV retinitis

Author(s):  
Ramakanth Gundu ◽  
Sanjay Pekamwar ◽  
Santosh Shelke ◽  
Deepak Kulkarni ◽  
Dipak Gadade

Abstract Valganciclovir HCl (VGH) is the widely used drug for the treatment of Cytomegalovirus (CMV) retinitis infection with an induction dose of 900mg twice a day and a maintenance dose of 900mg. This required dose of the drug also leads to multiple side effects due to repeated administration. The research was highlighted to develop, formulate, optimize and evaluate Single-Core Osmotic Pump (SCOP) tablet of VGH with the dose of 450mg to reduce dosing frequency and associated side effects. . The decrease in dose also minimize the hepatic and nephrotic load. The optimized batch of formulation was subjected to comparative in vitro and in vivo evaluation. The tablet core composition is the primary influencer of the drug delivery fraction in a zero-order, whereas the membrane characteristics control the drug release rate. In-vivo pharmacokinetic studies revealed that the newly developed osmotic formulation has controlled zero-order release for 24 hours with a single dose of 450mg while the marketed formulation requires twice administration within 24 hours to maintain the plasma concentration in the therapeutic window. The developed formulation can be the promising option for the treatment of CMV retinitis with the minimum dose and dosing frequency.

Cancers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1760 ◽  
Author(s):  
Michy ◽  
Massias ◽  
Bernard ◽  
Vanwonterghem ◽  
Henry ◽  
...  

Advanced ovarian cancer is the most lethal gynecological cancer, with a high rate of chemoresistance and relapse. Photodynamic therapy offers new prospects for ovarian cancer treatment, but current photosensitizers lack tumor specificity, resulting in low efficacy and significant side-effects. In the present work, the clinically approved photosensitizer verteporfin was encapsulated within nanostructured lipid carriers (NLC) for targeted photodynamic therapy of ovarian cancer. Cellular uptake and phototoxicity of free verteporfin and NLC-verteporfin were studied in vitro in human ovarian cancer cell lines cultured in 2D and 3D-spheroids, and biodistribution and photodynamic therapy were evaluated in vivo in mice. Both molecules were internalized in ovarian cancer cells and strongly inhibited tumor cells viability when exposed to laser light only. In vivo biodistribution and pharmacokinetic studies evidenced a long circulation time of NLC associated with efficient tumor uptake. Administration of 2 mg.kg−1 free verteporfin induced severe phototoxic adverse effects leading to the death of 5 out of 8 mice. In contrast, laser light exposure of tumors after intravenous administration of NLC-verteporfin (8 mg.kg−1) significantly inhibited tumor growth without visible toxicity. NLC-verteporfin thus led to efficient verteporfin vectorization to the tumor site and protection from side-effects, providing promising therapeutic prospects for photodynamic therapy of cancer.


2020 ◽  
Author(s):  
Xingyu He ◽  
Zheng Yuan ◽  
Samantha Gaeke ◽  
Winston W.-Y. Kao ◽  
S. Kevin Li ◽  
...  

AbstractThe current standard of care for posterior segment eye diseases, such as age-related macular degeneration and diabetic macular edema, is frequent intravitreal injections or sustained-release drug implants. Drug implants have side effects due to the burst release of the drugs, and their release cannot be easily controlled after implantation. Present study attempts to develop a dosage-controllable drug delivery implant which consists of a nanoporous biodegradable PLGA capsule and light-activated liposomes. Controllable drug release from the implant was achieved by using pulsed near-infrared (NIR) laser both in vitro and in vivo. The in vitro drug release kinetics from two different initial dose implants, 1000 μg and 500 μg, was analyzed by fitting zero order and first order kinetics, as well as the Korsmeyer-Peppas and Higuchi models. The 1000 μg and 500 μg implants fit the first-order and zero-order kinetics model, respectively, the best. The multiple drug releases in the vitreous was determined by in vivo fluorimeter, which was consistent with the in vitro data. The dose released was also clinically relevant. Histology and optical and ultrasound imaging data showed no abnormality in the eyes received implant treatment suggesting that the drug delivery system was safe to the retina. This on-demand dose-controllable drug delivery system could be potentially used for long-term posterior eye disease treatment.


Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1212
Author(s):  
Sibusiso Alven ◽  
Blessing Atim Aderibigbe

Breast cancer is among the most common types of cancer in women and it is the cause of a high rate of mortality globally. The use of anticancer drugs is the standard treatment approach used for this type of cancer. However, most of these drugs are limited by multi-drug resistance, drug toxicity, poor drug bioavailability, low water solubility, poor pharmacokinetics, etc. To overcome multi-drug resistance, combinations of two or more anticancer drugs are used. However, the combination of two or more anticancer drugs produce toxic side effects. Micelles and dendrimers are promising drug delivery systems that can overcome the limitations associated with the currently used anticancer drugs. They have the capability to overcome drug resistance, reduce drug toxicity, improve the drug solubility and bioavailability. Different classes of anticancer drugs have been loaded into micelles and dendrimers, resulting in targeted drug delivery, sustained drug release mechanism, increased cellular uptake, reduced toxic side effects of the loaded drugs with enhanced anticancer activity in vitro and in vivo. This review article reports the biological outcomes of dendrimers and micelles loaded with different known anticancer agents on breast cancer in vitro and in vivo.


Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 316 ◽  
Author(s):  
N. Raghavendra Naveen ◽  
Chakka Gopinath ◽  
Mallesh Kurakula

The success of mucoadhesive drug delivery systems relies on the type of polymer used, which becomes adhesive naturally upon hydration. Intended polymers should be able to maintain prolonged contact with biological membranes, and to protect or cater the drug to a prolonged period. Most of the hydro polymers form weak non-covalent bonds, that hinder localization of dosage forms at specific sites resulting in therapeutic inefficiency. This can be overcome by the thiol functionalization of natural polymers. In the present study, natural okra gum (OG) was extracted, followed by thiolation (TOG) and evaluated for mucoadhesion property and its role in enhancing the efficacy of repaglinide as a model drug (short-acting Type II antidiabetic drug). The thiol functionalization of OG (TOG) was confirmed by a Fourier-transform infrared spectroscopy (FTIR) study that showed a polyhedral to a spherical shape that had a rougher surface. Differential scanning calorimetry (DSC) and X-Ray Diffraction (XRD) studies of TOG indicated a decline in endothermic transition temperature and high crystallinity, respectively, in comparison to OG. CSFR (Crushing Strength: Friability Ratio), weight and thickness variations of repaglinidetablets formulated using TOG were >80% and <2.5% respectively. The highest swelling index (107.89 ± 1.99%) and strong mucoadhesion due to high disulfide bonds were observed for repaglinide TOG tablets in comparison to RG OG tablets. In-vitro release studies indicated a controlled drug release from thiolated formulations proportional to the concentration of thiomers that have a good correlation with in-vivo studies. Pharmacokinetic studies indicated higher AUC (area under the curve), longer t1/2 with thiomers. and Level A IVIV (in vitro in vivo) correlation was established from the bioavailability and dissolution data. Consequently, all the obtained results suggest that thiomers based formulations can be promising drug delivery systems, even in targeting onerous mucosal surfaces like nasal, ocular or vaginal.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi277-vi277
Author(s):  
Joelle P Straehla ◽  
Natalie Boehnke ◽  
Tamara G Dacoba ◽  
Paula T Hammond

Abstract Platinum-based agents remain a key component of therapy for children with medulloblastoma, despite significant systemic side effects and only modest blood-brain barrier (BBB) penetration. Cisplatin has a cerebrospinal fluid-to-plasma ratio <5% and dose-limiting side effects of nephrotoxicity, ototoxicity, and myelosuppression. Improving delivery of cisplatin across the BBB and selectively accumulating in tumors could improve its therapeutic index. To this end, we are leveraging chemical engineering techniques to rationally design cisplatin nanoparticles (NPs) to cross the BBB and preferentially enter medulloblastoma tumor cells. Using the layer-by-layer (LbL) platform to ‘wrap’ polyelectrolytes around a NP core by iterative electrostatic adsorption, we screened six negatively charged polypeptide and polysaccharide outer layers in medulloblastoma cell lines. Poly-L-aspartic acid (PLD) layered NPs had significant accumulation in tumor cells after 24 hours incubation, with an uptake index of 18±4 over unlayered control NPs. Next, we generated propargyl-functionalized PLD and used click chemistry to covalently conjugate the BBB shuttle ligands glutathione, angiopep-2, and transferrin, which have been shown to mediate transcytosis across brain endothelial cells. PLD layered NPs functionalized with angiopep-2 and transferrin had enhanced uptake in medulloblastoma tumor cells and NPs functionalized with glutathione were non-inferior to PLD layered NPs. After incubation with endothelial cells in vitro, all three BBB shuttle ligands enhanced uptake of PLD layered NPs over unlayered and non-functionalized control NPs. We then incorporated cisplatin into the nanoparticle core of this platform. Cisplatin-loaded NPs with PLD layering and ligand functionalization were more effective than free cisplatin as measured by IC50 over 72 hours in culture, and led to faster apoptosis as assessed by flow cytometry with annexin V and propidium iodide staining. In summary, functionalized nanoparticles are a promising platform to modulate drug delivery to medulloblastoma. In vivo studies using an orthotopic xenograft model are underway to investigate biodistribution, efficacy, and toxicity.


2008 ◽  
Vol 8 (5) ◽  
pp. 2205-2215 ◽  
Author(s):  
Ghaleb A. Husseini ◽  
William G. Pitt

The high toxicity of potent chemotherapeutic drugs like Doxorubicin (Dox) limits the therapeutic window in which they can be applied. This window can be expanded by controlling the drug delivery in both space and time such that non-targeted tissues are not adversely affected. Recent research has shown that ultrasound (US) can be used to control the release of Dox and other hydrophobic drugs from polymeric micelles in both time and space. It has also been shown using an in vivo rat tumor model that Dox activity can be enhanced by ultrasound in one region, while in an adjacent region there is little or no effect of the drug. In this article, we review the in vivo and in vitro research being conducted in the area of using ultrasound to enhance and target micellar drug delivery to cancerous tissues. Additionally, we summarize our previously published mathematical models that attempt to represent the release and re-encapsulation phenomena of Dox from Pluronic® P105 micelles upon the application of ultrasound. The potential benefits of such controlled chemotherapy compels a thorough investigation of the role of ultrasound (US) and the mechanisms by which US accomplishes drug release and/or enhances drug potency. Therefore we will summarize our findings related to the mechanism involved in acoustically activated micellar drug delivery to tumors.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 557
Author(s):  
Alka Prasher ◽  
Roopali Shrivastava ◽  
Denali Dahl ◽  
Preetika Sharma-Huynh ◽  
Panita Maturavongsadit ◽  
...  

Eosinophilic esophagitis (EoE) is a chronic atopic disease that has become increasingly prevalent over the past 20 years. A first-line pharmacologic option is topical/swallowed corticosteroids, but these are adapted from asthma preparations such as fluticasone from an inhaler and yield suboptimal response rates. There are no FDA-approved medications for the treatment of EoE, and esophageal-specific drug formulations are lacking. We report the development of two novel esophageal-specific drug delivery platforms. The first is a fluticasone-eluting string that could be swallowed similar to the string test “entero-test” and used for overnight treatment, allowing for a rapid release along the entire length of esophagus. In vitro drug release studies showed a target release of 1 mg/day of fluticasone. In vivo pharmacokinetic studies were carried out after deploying the string in a porcine model, and our results showed a high local level of fluticasone in esophageal tissue persisting over 1 and 3 days, and a minimal systemic absorption in plasma. The second device is a fluticasone-eluting 3D printed ring for local and sustained release of fluticasone in the esophagus. We designed and fabricated biocompatible fluticasone-loaded rings using a top-down, Digital Light Processing (DLP) Gizmo 3D printer. We explored various strategies of drug loading into 3D printed rings, involving incorporation of drug during the print process (pre-loading) or after printing (post-loading). In vitro drug release studies of fluticasone-loaded rings (pre and post-loaded) showed that fluticasone elutes at a constant rate over a period of one month. Ex vivo pharmacokinetic studies in the porcine model also showed high tissue levels of fluticasone and both rings and strings were successfully deployed into the porcine esophagus in vivo. Given these preliminary proof-of-concept data, these devices now merit study in animal models of disease and ultimately subsequent translation to testing in humans.


Author(s):  
S Srikanth Reddy ◽  
G Suresh

The current research is aimed at developing liquid self-nanoemulsifying drug delivery system (liquid-SNEDDS) of Manidipine for enhanced solubility and oral bioavailability. The Manidipine SNEDDS are formulated with excipients comprising of Capmul MCM (oil phase), Transcutol P (surfactant) Lutrol L 300 as co-surfactant. The prepared fifteen formulations of Manidipine SNEDDS analysed for emulsification time, percentage transmittance, particle size, in vitro drug release, and stability studies. In vivo pharmacokinetic studies of the optimized formulation were carried out in Wistar rats in comparison with control (pure drug). The morphology of Manidipine SNEDDS indicates spherical shape with uniform particle distribution. The percentage drug release from optimized formulation F14 is 98.24 ± 5.14%. The particle size F14 formulation was 22.4 nm and Z-Average 23.3 nm. The PDI and zeta potential of Manidipine SNEDDS optimized formulation (F14) were 0.313 and-5.1mV respectively. From in vivo bioavailability data the optimized formulation exhibited a significantly greater Cmax and Tmax of the SNEDDS was found to be 3.42 ± 0.46ng/ml and 2.00 ± 0.05 h respectively. AUC0-∞ infinity for formulation was significantly higher (11.25 ± 3.45 ng.h/ml) than pure drug (7.45 ± 2.24ng. h/ml). Hence a potential SNEDDS formulation of Manidipine developed with enhanced solubility and bioavailability.


2021 ◽  
Vol 12 ◽  
Author(s):  
Soraia Silva ◽  
Joana Bicker ◽  
Carla Fonseca ◽  
Nuno R. Ferreira ◽  
Carla Vitorino ◽  
...  

Depression is a common mental disorder. Its treatment with selective serotonin reuptake inhibitors (SSRIs) is effective only in a fraction of patients, and pharmacoresistance is increasing steadily. Intranasal (IN) drug delivery to the brain stands out as a promising strategy to improve current therapeutic approaches by operating as a shuttle to overcome the blood–brain barrier. This work aimed to simultaneously administer escitalopram and paroxetine by IN route to mice. For this purpose, three nanostructured lipid carriers (NLC1, NLC2, and BorNLC) and one nanoemulsion (NE) were tested for drug loading. After their characterization, investigation of their impact on nasal cell viability and SSRI permeability assays were performed, using a human nasal RPMI 2650 cell line in air–liquid interface. In vitro assays demonstrated that NLCs, including borneol (BorNLC), significantly increased escitalopram permeability (p &lt; 0.01) and paroxetine recovery values (p &lt; 0.05) in relation to the other formulations and non-encapsulated drugs. IN and intravenous (IV) pharmacokinetic studies performed in vivo with a single dose of 2.38 mg/kg demonstrated similar results for escitalopram brain-to-plasma ratios. IN administrations delayed escitalopram peak concentrations in the brain for 15–60 min and no direct nose-to-brain delivery was detected. However, encapsulation with BorNLC considerably decreased escitalopram exposure in the lungs (124 μg min/g) compared with free escitalopram by IN (168 μg min/g) and IV (321 μg min/g) routes. Surprisingly, BorNLC IN instillation increased concentration levels of paroxetine in the brain by five times and accelerated brain drug delivery. Once again, lung exposure was considerably lower with BorNLC (AUCt = 0.433 μg min/g) than that with IV administration (AUCt = 1.01 μg min/g) and non-encapsulated IN formulation (AUCt = 2.82 μg min/g). Direct nose-to-brain delivery was observed for paroxetine IN administration with a direct transport percentage (DTP) of 56.9%. If encapsulated, it increases to 74.2%. These results clearly emphasize that nose-to-brain delivery and lung exposure depend on the formulation and on the characteristics of the drug under investigation. NLCs seem to be an advantageous strategy for nose-to-brain delivery of lipophilic molecules, since they reduce systemic and lung exposure, thereby decreasing adverse effects. For hydrophilic compounds, NLCs are particularly important to decrease lung exposure after IN administration.


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