Development and optimization of levodopa and benzylhydrazine orally disintegrating tablets by direct compression and response surface methodology.

The number of Parkinson's disease (PD) patients with the advanced phase and motor fluctuations is increasing. The objective of this study is developing levodopa/benzylhydrazine orally disintegrating tablets (L/B ODTs), which would provide greater convenience and ease of use than conventional tablets for these patients. In the present study, the L/B ODTs were developed successfully with an optimized formulation using response surface methodology (RSM). The direct compression technology was employed for the preparation of L/B ODTs. Considerably shorter disintegration time and faster dissolution profile were obtained under the optimum formulation with microcrystalline cellulose 25.7%, cross-polyvinylpyrrolidone 6.22% and Sodium carboxymethyl starch 5.36%. The content uniformity (%) of levodopa and benzylhydrazine was 50 ± 1.4% and 14.25 ± 0.6%, respectively. Thickness, friability, hardness and wetting time were 2.8 ± 0.05 mm, 0.46 ± 0.21%, 5.42 ± 1.1 kp and 31.2 ± 2.1 s, respectively, and all of data well comply with the General Principles of the Chinese Pharmacopeia. Mannitol of 22% in formulation could bring a pleasant taste: sweet, cool and refreshing. Almost all the volunteers felt that the ODTs had good taste, no roughness, and no gritty feeling, indicating that the ODTs prepared had good palatability, so patients will have good compliance when taking medicine.

Eltrombopag and high-dose dexamethasone as frontline treatment of newly diagnosed immune thrombocytopenia in adults.

Immune thrombocytopenia (ITP) results from platelet destruction and production suppression. Eltrombopag belongs to a new class of thrombopoietin-mimetic drugs that raise platelet counts in ITP patients. We performed a single-arm study to assess the response to a single course of dexamethasone (40 mg by mouth, days 1-4) in combination with eltrombopag (50 mg, days 5-32) in 12 adults with newly diagnosed ITP in an outpatient setting. Median follow-up was 12.5 months. After therapy (day 33), 100% of patients achieved at least ≥30 × 10(9)/L platelets. Four patients relapsed. Complete response at 6 months (platelets ≥100 × 10(9)/L) was achieved in 50% of patients and response at 6 months (platelets ≥30 <100 × 10(9)/L) was achieved in another 25%; relapse-free survival was 66.7% at 12 months (median response duration of 8.3 months). In conclusion, eltrombopag/dexamethasone is a feasible frontline therapy for ITP. This trial is registered at www.clinicaltrials.gov as NCT01652599.

Modeling and simulation support eltrombopag dosing in thrombocytopenic patients with chronic HCV infection.

PURPOSE: The pharmacokinetics of eltrombopag and its stimulation of platelet production were characterized in patients with chronic hepatitis C virus (HCV) infection to optimize an eltrombopag dosing regimen for treatment of HCV-related thrombocytopenia before and throughout peginterferon (pegIFN)-based antiviral therapy. METHODS: Population pharmacokinetic analysis for eltrombopag included 663 individuals (healthy subjects, n = 28; patients with HCV, n = 635). Population pharmacokinetic/pharmacodynamic analysis for platelet response involved patients with HCV only. Simulations were conducted using various dosing scenarios in the same patient population. RESULTS: Eltrombopag pharmacokinetics were described by a two-compartment model with dual sequential first-order absorption and elimination. Age, race, sex, and severity of hepatic impairment were predictors of eltrombopag clearance. The effect of eltrombopag on platelet counts was adequately described by a model with four transit compartments in which eltrombopag concentrations stimulated the production rate of platelet precursors in an Emax manner. CONCLUSIONS: Modeling and simulation results support once-daily eltrombopag 25 mg as an appropriate starting dosing regimen followed by biweekly dose escalation (in 25-mg increments) up to once-daily eltrombopag 100 mg to raise platelet counts sufficiently for initiation of pegIFN-based antiviral therapy in patients with HCV. Biweekly dose adjustment allows patients to stay on the lowest possible eltrombopag dose during antiviral therapy.

Dental procedures in 24 patients with chronic immune thrombocytopenia in prospective clinical studies of eltrombopag.

Primary immune thrombocytopenia (ITP) is an autoimmune disease characterized by chronically low peripheral blood platelet counts. Eltrombopag is an oral, non-peptide, thrombopoietin-receptor agonist that increases platelet production. This report examines peri-procedural platelet counts and bleeding complications among chronic ITP patients requiring dental procedures while participating in clinical studies with eltrombopag. A total of 494 patients participated in five clinical studies of eltrombopag in chronic ITP. Information about dental procedures was collected prospectively in four studies and retrospectively in one study. Twenty-four patients (22 eltrombopag, 2 placebo) underwent 32 dental procedures (dental cleaning, tooth repair, artificial crown, dental prosthesis, tooth extraction, dental or wisdom teeth extraction, dental root extraction, and endodontic procedures, among others) during study treatment or up to 10 days later. Supplemental ITP therapy (e.g., corticosteroids, platelet transfusions) was given before the dental procedure to increase platelet counts in three eltrombopag-treated patients and both placebo-treated patients. The mean pre-procedure platelet count ± standard deviation for all procedures in the overall population of patients, eltrombopag group, and placebo group prior to undergoing dental procedures was 96 000 ± 81 069/µl,103 517 ± 81 522/µl, and 23 333 ± 9291/µl, respectively. Two patients in each group had platelet counts below 30 000/µl before the procedure. No patient who had a dental procedure experienced a bleeding adverse event. Among patients with chronic ITP who required a dental procedure during clinical studies of eltrombopag, supplemental ITP treatment was required for both patients who received placebo but was not required for most patients who received eltrombopag. No bleeding complications were reported. These data imply that patients with chronic ITP who receive eltrombopag and experience increases in platelet counts fulfill current pre-procedural platelet count recommendations to undergo invasive dental procedures, and may have a lower risk of bleeding complications and a reduced need for supplemental ITP treatment.

Role of growth factors and thrombopoietic agents in the treatment of chronic hepatitis C.

Advanced liver disease and interferon-based treatment are both associated with varying degrees of cytopenia in patients with chronic hepatitis C. Growth factors to increase hemoglobin and neutrophils are commonly used in clinical practice, despite the absence of data to indicate benefits in terms of sustained viral response. Thrombocytopenia is observed frequently, is multi-factorial in etiology, and may result in significant limitations on interventional and therapeutic options. A small-molecule thrombopoietin mimetic, eltrombo-pag, has demonstrated a dose-response associated increase in platelet count in a phase 2 study, allowing initiation and completion of a 12-week course of peginterferon plus ribavirin in 36%, 53%, and 65% of patients receiving 30 mg, 50 mg, or 75 mg of eltrombopag daily, respectively, compared with 6% in the placebo arm. Phase 3 studies are currently evaluating whether initiating and maintaining antiviral therapy with eltrombopag will lead to an increase in sustained virologic response in chronic hepatitis C infection.

Pro-inflammatory macrophage polarization enhances the anti-cancer efficacy of self-assembled galactomannan nanoparticles entrapped with hydrazinocurcumin.

Galactomannan (GM), a natural polymer, is recognized to specifically target macrophage mannose receptors (CD206). Interestingly, some reports indicate that GM has an ability to induce pro-inflammatory (M1-like, tumericidal) polarization in macrophages, suggesting its potential use as an anti-cancer agent. Hydrazinocurcumin (HC), a pyrazole derivative of curcumin, is reported to possess increased anti-cancer efficacy over curcumin. Moreover, HC-encapsulated nanoparticles (NPs) have been reported to re-polarize tumor-associated macrophages (TAMs) from anti-inflammatory (M2-like, tumor-promoting) to pro-inflammatory phenotype. To club the therapeutic properties of both GM and HC, we synthesized self-assembled amphiphilic PEGylated GM NPs loaded with HC (PSGM-HCNPs) and evaluated their potential to re-polarize TAMs towards M1-like phenotype. PSGM-HCNPs re-polarized IL-4 polarized RAW 264.7 cells via a phenotypic switch from M2- to M1-like by elevating ROS level, decreasing CD206 and arginase-1 expressions and increasing pro-inflammatory cytokines' secretion. Conditioned medium (CM) taken from re-polarized RAW 264.7 cells containing residual PSGM-HCNPs elevated ROS, arrested cell cycle, and induced apoptosis in 4T1, breast cancer cells, and Ehrlich's ascites carcinoma (EAC) cells. Decreased levels of MMP-2, MMP-9, and Bcl-2 with increased levels of Bax in both 4T1 and EAC cells indicated anti-metastatic and apoptosis-inducing potential of the CM. Treatment of PSGM-HCNPs in EAC-bearing mice reduced tumor burden, increased their survival time, decreased CD206+F4/80+ cells, and increased TNF-α+F4/80+ cells signifying decrease in M2- and increase in M1-like skewness among ascitic TAMs.

Pharmaceutical development and manufacturing of a parenteral formulation of a novel antitumor agent, VNP40101M.

The objective of this study was to develop and manufacture a stable parenteral formulation for Phase I clinical trials of VNP40101M (1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)-2-[(2-methylamino)carbonyl] hydrazine), a novel antitumor agent. The solubility and stability of the drug was determined. Solubility studies suggested that VNP40101M exhibited poor aqueous solubility but showed appreciable solubility in nonaqueous solvents. The aqueous solubility of the drug could not be increased by adjusting the pH. At a pH above 7, base-catalyzed decomposition of VNP40101M occurred. The low octanol-water partition coefficient of 0.75 suggested poor solubility in lipophilic solvents. Based on these preformulation observations, a parenteral formulation containing 10 mg/mL of VNP40101M was prepared in a solvent system consisting of 30% ethyl alcohol and 70% polyethylene glycol-300 (PEG-300). To minimize base-catalyzed hydrolytic degradation, citric acid at 0.6% concentration was included to acidify the formulation. Rubber closures, filter membranes, and liquid transfer tubing were selected on the basis of compatibility studies and absence of loss of drug due to adsorption of these components. The formulation was subjected to accelerated stability studies and dilution studies with large volume parenteral (LVP) solutions, normal saline, and 5% dextrose injection (D5W). The results of the dilution study indicated that the formulation could be diluted in these solutions up to 2 mg/mL for 8 hours without drug precipitation and degradation. Accelerated stability studies suggested that the product should be kept at 2 degrees C to 8 degrees C for long-term storage. The developed formulation was successfully scaled up and manufactured for use in clinical trials.

In vitro and in vivo analysis of the antithrombotic and toxicological profile of new antiplatelets N-acylhydrazone derivatives and development of nanosystems: determination of novel NAH derivatives antiplatelet and nanotechnological approach.

BACKGROUND: Cardiovascular diseases are the most frequent cause of morbidity and mortality worldwide. Among the most important cardiovascular diseases are atherothrombosis and venous thromboembolism that present platelet aggregation as a key event. Currently, the commercial antiplatelet agents display several undesirable effects, which prompt the search for new compounds with better therapeutic index, more efficient body distribution and mechanism. METHODS: In this work we characterized in vivo and in vitro the antithrombotic and toxicological profiles of novel antiplatelet N-substituted-phenylamino-5-methyl-1H-1,2,3-triazole-4-carbohydrazides derivatives also comparing them with aspirin. In addition we also analyzed the stability of the more active compound after encapsulation in PLGA or PCL nanoparticles and the release profile of these new nanosystems. RESULTS: The biological results revealed not only the selective effect against arachidonic acid-induced platelet aggregation mainly for compounds 2c, 2e and 2h but also their in vivo active profile on thromboembolism pulmonary animal model with better survival rates (e.g. 82%) than aspirin (33%). The overall toxicological profile was determined by in vitro (MTT reduction tests, neutral red uptake in kidney VERO cells and hemolysis assays) and in vivo (pulmonary embolism) assays that pointed 2c as the most promising derivative with potential as a lead compound. By using the nanoprecipitation technique 2c was loaded into PLGA and PCL nanoparticles showing controlled release profile over 21days according to our drug release tests. CONCLUSION: According to our results compound 2c is the most interesting derivative for further studies as it showed the best activity and toxicological profile also allowing the nanoencapsulation process. Thus 2c may assist in determining a new potential therapy with favorable pharmacokinetics for treatment of thrombotic disorders.

Ultrasound imaging of oxidative stress in vivo with chemically-generated gas microbubbles.

Ultrasound contrast agents (UCAs) have tremendous potential for in vivo molecular imaging because of their high sensitivity. However, the diagnostic potential of UCAs has been difficult to exploit because current UCAs are based on pre-formed microbubbles, which can only detect cell surface receptors. Here, we demonstrate that chemical reactions that generate gas forming molecules can be used to perform molecular imaging by ultrasound in vivo. This new approach was demonstrated by imaging reactive oxygen species in vivo with allylhydrazine, a liquid compound that is converted into nitrogen and propylene gas after reacting with radical oxidants. We demonstrate that allylhydrazine encapsulated within liposomes can detect a 10 micromolar concentration of radical oxidants by ultrasound, and can image oxidative stress in mice, induced by lipopolysaccharide, using a clinical ultrasound system. We anticipate numerous applications of chemically-generated microbubbles for molecular imaging by ultrasound, given ultrasound's ability to detect small increments above the gas saturation limit, its spatial resolution and widespread clinical use.

Hematopoietic growth factors in myelodysplastic syndromes.

Hematopoietic growth factors (HGFs) continue to be the most widely prescribed class of medications for patients with myelodysplastic syndromes (MDS), despite the advent of disease-modifying therapies for MDS (eg, azacitidine, decitabine, and lenalidomide) and the current absence of an MDS-specific US Food and Drug Administration (FDA)-approved indication for any of the HGFs. Erythropoiesis-stimulating agents (ESAs: epoetin alfa, darbepoetin alfa), myeloid growth factors (MGFs: filgrastim, pegfilgrastim, sargramostim), and the newest group of HGFs, thrombopoiesis-stimulating agents (TSAs: romiplostim, eltrombopag), can increase peripheral blood counts in some patients, and may ameliorate some of the signs and symptoms of MDS-associated bone marrow failure. Although HGFs are generally considered "supportive care" measures, recent data suggest that HGFs may alter the natural history of disease in MDS, either for better or worse. This review examines data on the safety and effectiveness of HGFs for patients with MDS.

What is the potential for thrombopoietic agents in acute leukemia?

In the 16 years since thrombopoietin was identified and cloned, much has been learned about its biochemistry, how it is regulated, and its involvement in a wide range of functions in a variety of cell lineages. The first generation of recombinant human thrombopoietins, rHuTPO and pegylated recombinant human megakaryocyte growth and development factor (PEG-rHuMGDF), were shown to increase platelet counts in patients with immune thrombocytopenia, in platelet apheresis donors, and in patients receiving nonmyeloablative chemotherapy. Their effects in patients with acute myeloid leukemia (AML) showed no benefit at a wide range of doses and schedules. The two second-generation TPO mimetics approved by the US Food and Drug Administration (FDA) for the treatment of ITP, romiplostim and eltrombopag, are now being studied in a number of thrombocytopenic disorders including those due to chemotherapy and hepatitis C. Since romiplostim is comparable to the first-generation recombinant thrombopoietins, it may not be beneficial in AML treatment; however, given its novel mechanism of action, eltrombopag may be a TPO potentiator and if given at the proper time during chemotherapy, may enable AML patients to recover platelet counts sooner.

State of the art clinical efficacy and safety evaluation of N-acetylcarnosine dipeptide ophthalmic prodrug. Principles for the delivery, self-bioactivation, molecular targets and interaction with a highly evolved histidyl-hydrazide structure in the treatment and therapeutic management of a group of sight-threatening eye diseases.

OBJECTIVE: The exact biological functions of the aminoacyl-histidine dipeptides in ophthalmology are still unknown but they are the subject of intensive research activities at Innovative Vision Products, Inc. (IVP). Numerous studies have demonstrated, both at the tissue and organelle levels, that naturally occuring imidazole containing peptidomimetics possess strong and specific antioxidant properties, by preventing and reducing the accumulation of oxidised products derived from the lipid peroxidation (LPO) of biological membranes. Carnosine has been shown to act as a competitive inhibitor of the non-enzymatic glycosylation of proteins.Thus, carnosine may prevent and reverse (de-link) the formation of the advanced glycation end-products (AGEs), whose accumulation in the ocular tissues has been proposed to play a direct role in the etiology and pathogenesis of cataract and diabetic ocular complications (DOC). Besides, histidine-containing dipeptides are believed to act as cytosolic buffering agents. AIMS: To compare the efficacy of L-carnosine and derivatives in inhibiting/reversing oxidative stress-induced reactions relevant for cataract pathogenesis. To assess the transglycation activity of carnosine versus representatives of a new group of synthetic carnosine histidyl-hydrazide analogs. To test the clinical efficacy of N-acetylcarnosine prodrug eye drops, developed by IVP's scientists, in decreasing the symptoms of age-related cataract. MAIN METHODS: Antioxidant activity of L-carnosine and N-acetylcarnosine was studied in liposomes, a model of lipid membranes. Iron/ascorbate was used for induction of LPO and peroxidation products were measured. Second-generation carnosine analogs were synthesized and tested vs. L-carnosine for their ability to reverse the glycation process, ultimately resulting in the formation of the AGEs. Visual acuity and glare sensitivity was measured before and after 9-month of topical administration of N-acetylcarnosine eye drops in a randomized placebo-controlled cohort of patients presenting age-related uncomplicated cataract and non-cataract subjects of the same age range. KEY FINDINGS: L-carnosine operates as aldehyde and reactive oxygen species (ROS) scavenger in aqueous and lipid environments, preventing ROS-induced damage to biomolecules. L-carnosine and histidyl-hydrazide analogs present transglycation properties which could be used to decrease the occurrence of long term complications of AGE formation in DOC and age-related cataracts. In the patented ophthalmic formulations, the designed leucyl-histidylhydrazide (not hydrolizable by carnosinase substrate) is endowed with a highly evolved structure optimized for the bioactivation of a N-acetylcarnosine dipeptide prodrug, targeting therapeutics of the main DOC: cataract, diabetic retinopathy, central retinal vein occlusion, central retinal artery occlusion and neovascular glaucoma. Besides, the data support the clinical application of N-acetylcarnosine lubricant eye drops to compensate corneal acidosis. Nine-month treatment with N-acetylcarnosine resulted in improved visual acuity in subjects with cataract. Glare sensitivity was improved in subjects with cataract and in non-cataract older subjects. The results from the matched studies indicate that the N-acetylcarnosine-laden therapeutic contact lenses increasing the intraocular and systemic absorption of the active dipeptide carnosine ingredient, are an effective and well-tolerated bandage lens for anterior segment disease and for post-operative management of LASEK patients.This allows practitioners to prescribe extended wear of therapeutic contact lenses loaded with N-acetylcarnosine during medical treatment of cataracts, ocular complications of diabetes, primary open-angle glaucoma and potentially creates a healthier eye and body environment during healing. A number of clinically developed with alliance groups famous International brands of patented by IVP N-acetylcarnosine lubricant eye drops (Can-C, IVP C and D-Smile) are described with a quick reference guide for completing a vendor official registration in EC countries, U.A.E., Indonesia, Japan for human and veterinary use. In a separate development series of data Carcinine (beta-alanylhistamine) significantly protected photoreceptors against light-induced apoptosis, suggesting that this compound is sufficiently resistant to degradation with enzymatic hydrolysis and can be used in vivo representing new strategies in the anti-apoptotic ophthalmic therapy. SIGNIFICANCE: Cataract is a major disease both in terms of number of people involved and economic impact. The research into causative factors and mechanisms to prevent the development of cataract is essential, particularly in developing countries where cataract surgery is often inaccessible. The results of this study provide a substantial basis for further evaluation of N-acetylcarnosine eye drops patented by IVP in the treatment and prevention of visual impairment in the temporal cross-sections of an older population several years apart. In the number of promotion studies this ophthalmic drug showed experimental and clinical potential for the non-surgical treatment of age-related cataracts. Comprehensive studies that investigate clinical, economic, and humanistic outcomes for the patient and society are conducted and will be described with different types of identified pharmacoeconomic evaluations to adequately assess the comparative value of current N-acetylcarnosine eye drops therapeutics for medical care and its place in future ophthalmic practices. Patients and the public expect that safe and cost-effective cataract medical care with N-acetylcarnosine therapeutic platform should be commissioned for them.

L-dopa therapy combined with peripheral decarboxylase inhibitor (MK-486) in Parkinsonism.

Eighteen patients with parkinsonism were treated with a combination of L-dopa and peripheral decarboxylase inhibitor, L-alphahydrazinomethyldopa (MK-486). Modification of L-dopa effect by MK-486 was also studied in parkinsonian patients as well as in cats. (1) Concentrations of dopa and dopamine in plasma and brain were measured in cats following intraperitoneal injection of L-dopa alone (100 mg/kg) or combined with MK-486 (10 mg/kg). Dopa levels in plasma and brain in the combination with MK-486 were three times as high as in L-dopa alone. Dopamine levels in caudate nucleus and putamen were increased nearly fourfold with the combination. (2) Plasma dopa and dopamine levels were measured in parkinsonian patients. Clinical pharmacological studies disclosed that a 1 : 10 ratio of MK-486 to L-dopa in dosage was preferable. (3) Maximum plasma dopa levels with the combination were four times those following L-dopa alone. Plasma dopa sustained a high level over a period of five hours. MK-486 markedly reduced plasma levels of dopamine. (4) There was no significant difference in dopa and dopamine levels in cerebrospinal fluid between L-dopa alone and a combination of MK-486, but dopamine levels in the CSF were still high at four hours after the combination of MK-486. (5) In clinical studies of eighteen patients with parkinsonism, the effectiveness of the combination therapy (mean dosage of L-dopa: 750 mg/day) was observed in all cases. Marked improvement was noted in 10 cases out of 15 (67%) with akinesia, in 12 cases out of 17 (71%) with rigidity and in six cases out of 14 (43%) with tremor. Maximum plasma dopa levels were higher in those cases with marked improvement, and were highest in patients with diskinesias as a side effect. (6) An addition of vitamin B6 did not show adverse effects. (7) Transient nausea and vomiting as a side effect, less severe than those experienced with L-dopa alone, were noted in five cases (28%). Dyskinesias in extremities, face, mouth and tongue were observed in six cases (33%). These dyskinesias were seen in a high percentage of cases with marked improvement and were never observed in the extremities contralateral to the side of thalamotomy.