A structural and metabolic framework for classifying pre-clinical tuberculosis infection phenotypes using 18F-FDG PET-CT: a prospective cohort analysis following M. tuberculosis exposure.

Tuberculosis (TB) control efforts are limited by ineffective characterisation of tuberculosis infection (TBI) -a heterogeneous spectrum of pre-clinical infection states, invisible to tools of routine clinical screening, that are associated with variable risk of progression to TB disease. In this prospective study, we use positron emission tomography-CT (PET-CT) as a high-resolution imaging modality to characterise and classify structural and metabolic features observed in 16 asymptomatic household TB contacts with normal chest radiographs. We identify four feature patterns that associate with distinct clinical and microbiological outcomes, supporting potential utility of PET-CT for objective classification of TBI phenotypes.

Abemaciclib in patients with p16ink4A-deficient mesothelioma (MiST2): a single-arm, open-label, phase 2 trial.

BACKGROUND: Genetically stratified therapy for malignant mesothelioma is unavailable. Mesotheliomas frequently harbour loss of the chromosome 9p21.3 locus (CDKN2A-MTAP), which is associated with shorter overall survival due to loss of the tumour suppressor p16ink4A, an endogenous suppressor of cyclin-dependent kinase (CDK)4 and CDK6. Genetic restoration of p16ink4A suppresses mesothelioma in preclinical models, underpinning the rationale for targeting CDK4 and CDK6 in p16ink4A-negative mesothelioma. We developed a multicentre, stratified, phase 2 trial to test this hypothesis. METHODS: The MiST2 study was a single-arm, open-label, phase 2 clinical trial done two UK centres. Patients older than 18 years with any histologically confirmed subtype of mesothelioma (pleural or peritoneal) with radiological progression after at least one course of platinum-based chemotherapy were molecularly screened by immunohistochemistry for p16ink4A. Patients with p16ink4A-negative mesothelioma were eligible for inclusion in the study. Patients were required to have measurable disease by modified Response Evaluation Criteria in Solid Tumours version 1.1 for malignant mesothelioma, a predicted life expectancy of at least 12 weeks, and an Eastern Cooperative Oncology Group performance status score of 0-1. Patients received oral abemaciclib 200 mg twice daily, administered in 28-day cycles for 24 weeks. The primary endpoint was the disease control rate (patients with complete responses, partial responses, or stable disease) at 12 weeks. The null hypothesis could be rejected if at least 11 patients had disease control. The efficacy and safety populations were defined as all patients who received at least one dose of the study drug. The study is registered with ClinicalTrials.gov, NCT03654833, and is ongoing (but MiST2 is now closed). FINDINGS: Between Sept 31, 2019, and March 2, 2020, 27 eligible patients consented to molecular screening. The median follow-up was 18·4 weeks (IQR 6·7-23·9). One patient was excluded before treatment because of a serious adverse event before study drug allocation. 26 (100%) of 26 treated patients were p16ink4A deficient and received at least one dose of abemaciclib. Disease control at 12 weeks was reported in 14 (54%) of 26 patients (95% CI 36-71). Grade 3 or worse treatment-related adverse events (of any cause) occurred in eight (27%) of 26 patients (diarrhoea, dyspnoea, thrombocytopenia, vomiting, urinary tract infection, increased alanine aminotransferase, ascites, chest infection or suspected chest infection, neutropenic sepsis, alopecia, blood clot left calf, fall [broken neck and collar bone], haemoptysis, lower respiratory tract infection, and pulmonary embolism). Grade 3 or worse treatment-related adverse events occurred in three (12%) of 26 patients (diarrhoea, thrombocytopenia, vomiting, increased alanine aminotransferase, and pulmonary embolism). Serious adverse events occurred in six (23%) of 26 patients, leading to treatment discontinuation in one (4%) patient (diarrhoea, urinary tract infection, chest infection, neutropenic sepsis, fall [broken neck and collar bone], haemoptysis, lower respiratory tract infection, and pulmonary embolism). One patient had a serious adverse event related to abemaciclib (diarrhoea). One (4%) of 26 patients died from an adverse event (neutropenic sepsis). INTERPRETATION: This study met its primary endpoint, showing promising clinical activity of abemaciclib in patients with p16ink4A-negative mesothelioma who were previously treated with chemotherapy, and warrants its further investigation in a randomised study as a targeted stratified therapy. FUNDING: University of Leicester, Asthma UK and British Lung Foundation Partnership, and the Victor Dahdaleh Foundation.

Pharmacokinetics and pharmacodynamics of intranasally administered selegiline nanoparticles with improved brain delivery in Parkinson's disease.

Selegiline, a well-known anti-Parkinson agent, is reported to be associated with poor oral bioavailability and safety. Therefore, we formulated selegiline as chitosan nanoparticles and evaluated its pharmacokinetics and pharmacodynamics after intranasal administration to rats relative to those after oral administration. The optimized formulation exhibited spherical nanoparticles with more than 90% drug loading and steady in vitro and ex vivo drug release. Selegiline concentrations in the brain and plasma were 20- and 12-fold higher, respectively, after intranasal administration than after oral administration. Treatment with intranasal nanoparticles was also associated with better performance in locomotor activity, catalepsy, and stride length tests and significantly increased dopamine, catalase activity, and glutathione content in the brain. Therefore, intranasally administered selegiline nanoparticles holds superior therapeutic value compared to oral administration and can be a promising approach for the treatment of Parkinson's disease.

Evaluation of anti-metastatic potential of Cisplatin polymeric nanocarriers on B16F10 melanoma cells.

Nanoparticles are being increasingly used in the field of cancer treatment due to their unique properties and advantages. The aim of the present research work was to prepare and characterize a polymeric albumin nanosystem for Cisplatin and evaluate its in-vitro efficacy against B16F10 melanoma. The developed nanoparticles were almost spherical in shape with a particle size in the range of 150-300 nm, low polydispersity values and about 80% drug entrapment efficiency. Albumin nanocarriers sustained the release of Cisplatin for more than 48 h, suggesting the reduction in dosing schedule for this drug. The results from in-vitro cell line studies indicated the dose dependent cytotoxic potential of drug loaded albumin nanoparticles, their potential to inhibit cell proliferation and induce morphological changes. In addition, these nanoparticles exhibited superiority to Cisplatin in hampering the cell migration. Developed nanoparticles caused cell cycle arrest along with time and concentration dependent cellular uptake in B16F10 cell line. These results signify that the prepared Cisplatin albumin nanoparticles could serve as a promising approach for B16F10 melanoma treatment.

Unraveling the cytotoxic potential of Temozolomide loaded into PLGA nanoparticles.

BACKGROUND: Nanotechnology has received great attention since a decade for the treatment of different varieties of cancer. However, there is a limited data available on the cytotoxic potential of Temozolomide (TMZ) formulations. In the current research work, an attempt has been made to understand the anti-metastatic effect of the drug after loading into PLGA nanoparticles against C6 glioma cells.Nanoparticles were prepared using solvent diffusion method and were characterized for size and morphology. Diffusion of the drug from the nanoparticles was studied by dialysis method. The designed nanoparticles were also assessed for cellular uptake using confocal microscopy and flow cytometry. RESULTS: PLGA nanoparticles caused a sustained release of the drug and showed a higher cellular uptake. The drug formulations also affected the cellular proliferation and motility. CONCLUSION: PLGA coated nanoparticles prolong the activity of the loaded drug while retaining the anti-metastatic activity.

A gut microbiota rheostat forecasts responsiveness to PD-L1 and VEGF blockade in mesothelioma.

Malignant mesothelioma is a rare tumour caused by asbestos exposure that originates mainly from the pleural lining or the peritoneum. Treatment options are limited, and the prognosis is dismal. Although immune checkpoint blockade (ICB) can improve survival outcomes, the determinants of responsiveness remain elusive. Here, we report the outcomes of a multi-centre phase II clinical trial (MiST4, NCT03654833) evaluating atezolizumab and bevacizumab (AtzBev) in patients with relapsed mesothelioma. We also use tumour tissue and gut microbiome sequencing, as well as tumour spatial immunophenotyping to identify factors associated with treatment response. MIST4 met its primary endpoint with 50% 12-week disease control, and the treatment was tolerable. Aneuploidy, notably uniparental disomy (UPD), homologous recombination deficiency (HRD), epithelial-mesenchymal transition and inflammation with CD68+ monocytes were identified as tumour-intrinsic resistance factors. The log-ratio of gut-resident microbial genera positively correlated with radiological response to AtzBev and CD8+ T cell infiltration, but was inversely correlated with UPD, HRD and tumour infiltration by CD68+ monocytes. In summary, a model is proposed in which both intrinsic and extrinsic determinants in mesothelioma cooperate to modify the tumour microenvironment and confer clinical sensitivity to AtzBev. Gut microbiota represent a potentially modifiable factor with potential to improve immunotherapy outcomes for individuals with this cancer of unmet need.

Self-nanoemulsifying drug delivery system of cefpodoxime proxetil containing tocopherol polyethylene glycol succinate.

CONTEXT: Lipid based drug delivery systems have gained prominence in last decade for drugs with dissolution rate limited oral bioavailability. OBJECTIVE: To improve the solubility, permeability and oral bioavailability of cefpodoxime proxetil, ß-lactam antibiotic. It is BCS Class IV drug having solubility 400 µg/mL and 50% oral bioavailability. MATERIALS AND METHODS: Self-nanoemulsifying drug delivery system (SNEDDS) using various surfactant and cosurfactants such as tween 80, tocopheryl polyethylene glycol succinate (TPGS), propylene glycol and Capmul MCM as oil phase were prepared. Ternary phase diagrams were constructed to identify stable microemulsion region. Percent transmittance studies helped to shortlist the surfactant-cosurfactant combination. RESULTS AND DISCUSSION: Tween 80 and TPGS as surfactants and Capmul MCM as oil phase were found to produce stable nanoemulsions. Five formulations of SNEDDS had globule size of 55-60 nm and zeta potential of -4 to -11 mV. Self-emulsification time was between 221 and 370 s, while viscosity was dependent on composition of SNEDDS. Cloud point was above 70°C which indicated the retention of in vivo self-emulsifying properties. Average flux for cefpodoxime proxetil (CP) and SNEDDS was 0.104 and 0.985 µg/cm(2) min. Permeability was 19.72 and 206 for CP and SNEDDS. Liquid SNEDDS spray coated onto micropellets of microcrystalline cellulose (18-20#) were analysed by scanning electron microscope (SEM), self-emulsification and in vitro dissolution. A 5.36-fold increase in area under curve AUC(0-∞) was observed for CP-SNEDDS than plain drug. Minimum inhibitory concentration (MIC) was lower for SNEDDS. Liquid and SNEDDS micropellets were stable under accelerated conditions. CONCLUSION: SNEDDS formulations led to improved oral bioavailability due to enhanced solubilization of selected drug.

Nanocrystallization by evaporative antisolvent technique for solubility and bioavailability enhancement of telmisartan.

Telmisartan is an orally active nonpeptide angiotensin II receptor antagonist used in the management of hypertension. It is a Biopharmaceutics Classification System class II drug having aqueous solubility of 9.9 µg/ml. Telmisartan (TEL) nanocrystals were prepared by evaporative antisolvent precipitation technique using different stabilizers as PVPK30, TPGS, Poloxamer 188, and PEG 6000 in combination or singly. The nanosuspensions were characterized in terms of particle size distribution, zeta potential, and polydispersity index. The suspension containing PVPK30 and TPGS (1:1) showed least average particle size of 82.63 nm and polydispersity index of 0.472. The zeta potential of nanosuspensions ranged between 6.54 and 10.8 mV. An increase of 116.45% was evident in the specific surface area of the freeze-dried product. Contact angle of nanoparticles was also lowered to 27° as compared to 50.8° for TEL. Saturation solubility studies in various media revealed a significant increase in comparison to plain drug. An increase of 3.74× in saturation solubility in FaSSIF and 5.02× in FeSSIF was seen. In vitro dissolution profile of nanosuspension coated on pellets revealed release of 85% in water, 95% in 0.1 N HCl, and 75% in phosphate buffer in 30 min. Nanosuspensions were found to be stable in the presence of univalent and bivalent electrolytes. A tenfold increase in bioavailability was evident. Nanoparticles of telmisartan prepared by bottom-up technique proved to be effective in improving the oral bioavailability as a result of enhanced solubility and dissolution rate.

True thymic hyperplasia causing pure red cell aplasia: a case report.

Pure red cell aplasia caused by true thymic hyperplasia is extremely rare. We report the case of a 25-year-old female diagnosed with pure red cell aplasia. Following a thymectomy confirming true thymic hyperplasia and corticosteroid therapy, complete response was achieved. Patients diagnosed with pure red cell aplasia should be investigated with a computerized tomographic scan to assess for thymic pathology and if present, this should be resected. Follow-up is essential to monitor for recurrence.

Constructing custom-made radiotranscriptomic signatures of vascular inflammation from routine CT angiograms: a prospective outcomes validation study in COVID-19.

BACKGROUND: Direct evaluation of vascular inflammation in patients with COVID-19 would facilitate more efficient trials of new treatments and identify patients at risk of long-term complications who might respond to treatment. We aimed to develop a novel artificial intelligence (AI)-assisted image analysis platform that quantifies cytokine-driven vascular inflammation from routine CT angiograms, and sought to validate its prognostic value in COVID-19. METHODS: For this prospective outcomes validation study, we developed a radiotranscriptomic platform that uses RNA sequencing data from human internal mammary artery biopsies to develop novel radiomic signatures of vascular inflammation from CT angiography images. We then used this platform to train a radiotranscriptomic signature (C19-RS), derived from the perivascular space around the aorta and the internal mammary artery, to best describe cytokine-driven vascular inflammation. The prognostic value of C19-RS was validated externally in 435 patients (331 from study arm 3 and 104 from study arm 4) admitted to hospital with or without COVID-19, undergoing clinically indicated pulmonary CT angiography, in three UK National Health Service (NHS) trusts (Oxford, Leicester, and Bath). We evaluated the diagnostic and prognostic value of C19-RS for death in hospital due to COVID-19, did sensitivity analyses based on dexamethasone treatment, and investigated the correlation of C19-RS with systemic transcriptomic changes. FINDINGS: Patients with COVID-19 had higher C19-RS than those without (adjusted odds ratio [OR] 2·97 [95% CI 1·43-6·27], p=0·0038), and those infected with the B.1.1.7 (alpha) SARS-CoV-2 variant had higher C19-RS values than those infected with the wild-type SARS-CoV-2 variant (adjusted OR 1·89 [95% CI 1·17-3·20] per SD, p=0·012). C19-RS had prognostic value for in-hospital mortality in COVID-19 in two testing cohorts (high [≥6·99] vs low [<6·99] C19-RS; hazard ratio [HR] 3·31 [95% CI 1·49-7·33], p=0·0033; and 2·58 [1·10-6·05], p=0·028), adjusted for clinical factors, biochemical biomarkers of inflammation and myocardial injury, and technical parameters. The adjusted HR for in-hospital mortality was 8·24 (95% CI 2·16-31·36, p=0·0019) in patients who received no dexamethasone treatment, but 2·27 (0·69-7·55, p=0·18) in those who received dexamethasone after the scan, suggesting that vascular inflammation might have been a therapeutic target of dexamethasone in COVID-19. Finally, C19-RS was strongly associated (r=0·61, p=0·00031) with a whole blood transcriptional module representing dysregulation of coagulation and platelet aggregation pathways. INTERPRETATION: Radiotranscriptomic analysis of CT angiography scans introduces a potentially powerful new platform for the development of non-invasive imaging biomarkers. Application of this platform in routine CT pulmonary angiography scans done in patients with COVID-19 produced the radiotranscriptomic signature C19-RS, a marker of cytokine-driven inflammation driving systemic activation of coagulation and responsible for adverse clinical outcomes, which predicts in-hospital mortality and might allow targeted therapy. FUNDING: Engineering and Physical Sciences Research Council, British Heart Foundation, Oxford BHF Centre of Research Excellence, Innovate UK, NIHR Oxford Biomedical Research Centre, Wellcome Trust, Onassis Foundation.

Diagnostic dilemma of Hodgkin's lymphoma versus tuberculosis: a case report and review of the literature.

BACKGROUND: Hodgkin's Lymphoma (HL) is a rare malignancy characterised histologically by the presence of Reed-Sternberg cells. Diagnosis of lymphomas can be difficult due to broad, non-specific presentations of disease, which can be similar to several other conditions ranging from infective, inflammatory or malignant causes, with one of the most common differentials being tuberculosis (TB). We aim to highlight the diagnostic dilemma of TB versus lymphoma with an atypical presentation of HL and explored areas for further research and improvement with a non-systematic literature review using MEDLINE database and Google Scholar. Written consent was obtained from the patient in compliance with ethical guidelines. CASE PRESENTATION: A 23-year-old Asian female initially presented to rheumatology with over a one-year history of neuropathic pain, alongside abnormal white cell count and inflammatory markers. This was investigated with magnetic resonance imaging resulting in an incidental finding of mediastinal mass and pulmonary infiltrates. An initial diagnosis of TB was made despite testing negative for acid-fast bacilli and anti-tubercular treatment was commenced. Four months later, following clinical deterioration and further investigations, a mediastinal biopsy assisted in diagnosing Stage IV HL. CONCLUSIONS: Lymphoma is often misdiagnosed as TB, prolonging time to treatment and may adversely impact patient prognosis due to disease progression. Existing TB guidelines for smear-negative cases are not clear when to consider alternative diagnoses. In smear-negative TB, lymphoma should be considered as a differential and definitive diagnostic tests such as molecular testing and histological examination of biopsies should be considered earlier in the diagnostic work-up to prevent diagnostic delay.

Clonal architecture in mesothelioma is prognostic and shapes the tumour microenvironment.

Malignant Pleural Mesothelioma (MPM) is typically diagnosed 20-50 years after exposure to asbestos and evolves along an unknown evolutionary trajectory. To elucidate this path, we conducted multi-regional exome sequencing of 90 tumour samples from 22 MPMs acquired at surgery. Here we show that exomic intratumour heterogeneity varies widely across the cohort. Phylogenetic tree topology ranges from linear to highly branched, reflecting a steep gradient of genomic instability. Using transfer learning, we detect repeated evolution, resolving 5 clusters that are prognostic, with temporally ordered clonal drivers. BAP1/-3p21 and FBXW7/-chr4 events are always early clonal. In contrast, NF2/-22q events, leading to Hippo pathway inactivation are predominantly late clonal, positively selected, and when subclonal, exhibit parallel evolution indicating an evolutionary constraint. Very late somatic alteration of NF2/22q occurred in one patient 12 years after surgery. Clonal architecture and evolutionary clusters dictate MPM inflammation and immune evasion. These results reveal potentially drugable evolutionary bottlenecking in MPM, and an impact of clonal architecture on shaping the immune landscape, with potential to dictate the clinical response to immune checkpoint inhibition.

Preparation and in vivo efficacy study of pancreatin microparticles as an enzyme replacement therapy for pancreatitis.

Deficiency manifestations because of pancreatic insufficiency are treated by oral administration of pancreatic enzymes. As pancreatic enzymes get denatured in hostile acidic conditions of stomach, this investigation was aimed at formulating multiparticulates of pancreatic enzymes coated with enteric polymers such as eudragit L100, cellulose acetate phthalate, and hydroxyl propyl methyl cellulose phthalate, which will circumvent gastric inactivation in addition to providing optimal mixing with chyme. Pancreatin microspheres were prepared by emulsification phase separation by nonsolvent addition and solvent evaporation techniques. This process was optimized for core : coat ratio (1:0.5), stirrer speed (350-400 rpm), dispersant concentration, and amount of nonsolvent added to precipitate microspheres. Optimized formulations were assessed for % enzyme content, acid resistance, flow properties, particle size, particle morphology (by standard electron microscopy), compatibility of drug and polymer in formulation (by differential scanning calorimetry), in vitro release kinetics, and in vivo efficacy study in pancreatitis-induced animal model. Capsules containing enteric-coated pancreatin microspheres offered adequate protection to enzymes and prevented their denaturation in acidic environment. Developed multiparticulate dosage forms promoted effective mixing, instant and complete in vitro release compared with marketed tablets.

Development of microsponges for topical delivery of mupirocin.

The goal of the present study was to develop and evaluate microsponge-based topical delivery system of mupirocin for sustained release and enhanced drug deposition in the skin. Microsponges containing mupirocin were prepared by an emulsion solvent diffusion method. The effect of formulation and process variables such as internal phase volume and stirring speed on the physical characteristics of microsponges were examined on optimized drug/polymer ratio by 3(2) factorial design. The optimized microsponges were incorporated into an emulgel base. In vitro drug release, ex vivo drug deposition, and in vivo antibacterial activity of mupirocin-loaded formulations were studied. Developed microsponges were spherical and porous, and there was no interaction between drug and polymer molecules. Emulgels containing microsponges showed desired physical properties. Drug release through cellulose dialysis membrane showed diffusion-controlled release pattern and drug deposition studies using rat abdominal skin exhibited significant retention of active in skin from microsponge-based formulations by 24 h. The optimized formulations were stable and nonirritant to skin as demonstrated by Draize patch test. Microsponges-based emulgel formulations showed prolonged efficacy in mouse surgical wound model infected with S. aureus. Mupirocin was stable in topical emulgel formulations and showed enhanced retention in the skin indicating better potential of the delivery system for treatment of primary and secondary skin infections, such as impetigo, eczema, and atopic dermatitis.

Development of budesonide microparticles using spray-drying technology for pulmonary administration: design, characterization, in vitro evaluation, and in vivo efficacy study.

The purpose of this research was to generate, characterize, and investigate the in vivo efficacy of budesonide (BUD) microparticles prepared by spray-drying technology with a potential application as carriers for pulmonary administration with sustained-release profile and improved respirable fraction. Microspheres and porous particles of chitosan (drug/chitosan, 1:2) were prepared by spray drying using optimized process parameters and were characterized for different physicochemical parameters. Mass median aerodynamic diameter and geometric standard deviation for conventional, microspheres, and porous particles formulations were 2.75, 4.60, and 4.30 microm and 2.56, 1.75, and 2.54, respectively. Pharmacokinetic study was performed in rats by intratracheal administration of either placebo or developed dry powder inhalation (DPI) formulation. Pharmacokinetic parameters were calculated (Ka, Ke, T(max), C(max), AUC, and Vd) and these results indicated that developed formulations extended half life compared to conventional formulation with onefold to fourfold improved local and systemic bioavailability. Estimates of relative bioavailability suggested that developed formulations have excellent lung deposition characteristics with extended T(1/2) from 9.4 to 14 h compared to conventional formulation. Anti-inflammatory activity of BUD and developed formulations was compared and found to be similar. Cytotoxicity was determined in A549 alveolar epithelial cell line and found to be not toxic. In vivo pulmonary deposition of developed conventional formulation was studied using gamma scintigraphy and results indicated potential in vitro-in vivo correlation in performance of conventional BUD DPI formulation. From the DPI formulation prepared with porous particles, the concentration of BUD increased fourfold in the lungs, indicating pulmonary targeting potential of developed formulations.

Haemodynamic effects of pharmacologic stress with adenosine in patients with left ventricular systolic dysfunction.

BACKGROUND: In patients with heart failure, downregulation of adenosine receptor gene expression and impaired adenosine-related signal transduction may result in a diminished response to adenosine. This may have implications for cardiac stress testing. We evaluated the haemodynamic response to intravenous adenosine in patients with left ventricular systolic dysfunction (LVSD) undergoing stress cardiovascular magnetic resonance imaging (CMR). METHODS AND RESULTS: We retrospectively examined 497 consecutive patients referred for clinical stress CMR. Blood pressure and heart rate responses with intravenous adenosine were compared in patients with normal, mild-moderately impaired and severely impaired LV systolic function (ejection fraction [EF] > 55%, 36-55% and < 35%, respectively). Following 2 min of adenosine infusion, there was a significant difference between the groups in the heart rate change from baseline, with a diminished heart rate response in patients with LVSD (p < 0.001). An increase in the dose of adenosine (up to 210 µg/kg/min) was required to achieve a sufficient haemodynamic response in more patients with severe LVSD (41%) than those with mild-moderately impaired and normal LV systolic function (24% and 19%, respectively, p < 0.001). Even with increased doses of adenosine in subjects with severe LVSD, peak haemodynamic response remained blunted. With multivariate analysis age (p < 0.001) and LVEF (p = 0.031) were independent predictors of heart rate response to adenosine. CONCLUSION: Patients with reduced LVEF referred for stress CMR may have a blunted heart rate response to adenosine. Further study is warranted to determine whether this may be associated with reduced diagnostic accuracy and also the potential utility of further dose increases or alternative stressors.

Development and evaluation of push-pull based osmotic delivery system for pramipexole.

An oral push-pull system that can deliver pramipexole for extended period of time has been developed and characterized. A bilayer osmotic drug delivery system was developed using a basic design consisting of an oral controlled porosity osmotic pump. Unlike other osmotic systems, which require a preformed orifice for drug release, controlled porosity membranes contain water-soluble pore-formers in the coating membrane. When such systems come in contact with water, the additives dissolve resulting in an in-situ formation of a microporous membrane. The push layer swells releasing the drug at a controlled rate. In advanced Parkinson's disease the usual dose of pramipexole is 1.5 mg three to four times a day. Hence, an attempt was made to develop a once-a-day controlled release system. This may offer significant patient benefits by providing enhanced efficacy and reduced side effects and may also reduce the number of daily doses compared to conventional therapies. This developed push-pull system was compared with other types of osmotic delivery systems, such as an asymmetric membrane coating and a dense coat with mechanical drilling. An optimized system was selected to study the effect of the concentration of a pore-forming agent such as PEG 400 and dibutyl phthalate, the pH of dissolution media, the effect of agitation and osmotic agents on drug release. The osmotic pressure generated was determined using a 3D3 freezing point osmometer. The drug release was found to follow zero order kinetics. Drug release increased with an increase in osmotic pressure. The developed push-pull osmotic system showed the desired once-a-day release kinetics.

Brain targeted delivery of mucoadhesive thermosensitive nasal gel of selegiline hydrochloride for treatment of Parkinson's disease.

Selegiline hydrochloride (SL), is an anti-Parkinson's agent, has low-oral bioavailability due to its high first pass metabolism and scarce oral absorption. In the present study, SL mucoadhesive nasal thermosensitive gel (SNT-gel) was prepared to enhance the bioavailability and subsequently, its concentration in the brain. The SNT-gel was prepared using Poloxamer 407-Chitosan combination and optimised formulation was further evaluated for physicochemical parameters. The comparative pharmacodynamic studies including behavioural studies, biochemical testing and histopathology of the brain was carried out in rats for SNT-gel, SL-nasal solution and SL Marketed Tablets. The optimised SNT-gel formulation (SNT-V) revealed sol-gel transition at 33-34°C. In-vitro diffusion study of SNT-V showed 102.37 ± 2.1% diffusion at 12 h which reduced to 89.64 ± 1.2% in Ex-vivo diffusion. Comparative results of behavioural studies indicated an improved score of photoactometer and reduced motor deficit (catalepsy score) in SNT-gel treatment group as compared with other groups. Similarly, a significant increase in brain dopamine, reduction in monoamine oxidase B level, increase in catalase activity and level of reduced glutathione upon treatment with SNT-gel indicated its effectiveness which was also supported by histopathology results. Therefore, nasal thermosensitive gel holds better potential for brain targeting in Parkinson's disease over the conventional nasal or oral formulations.

Fabrication of topical metered dose film forming sprays for pain management.

Topical film-forming metered dose spray formulations were designed for management of pain. Ropivacaine, a local anesthetic is explored for its topical efficacy in alleviating pain. Metered dose spray containers, organic solvents, film forming polymers and permeation enhancers were utilized to fabricate the Metered Dose topical spray. Factors like viscosity, spray pattern, spray angle, volume of actuation, droplet size distribution of the metered dose spray formulation and drying time, flexibility and wash-ability of the film formed after spraying were assessed. Permeation of the drug into the porcine skin was observed based on ex-vivo diffusion studies and confocal microscopy. The results indicated a high level of drug concentration in the skin layers. Anti-nociceptive efficacy of the formulations was assessed on Wistar rats by hot plate and tail flick tests, based on the response to pain perception. The results were comparable to the conventional lidocaine gel. Topical film forming sprays have the ability to provide an accurate, long lasting and patient compliant delivery of drugs on the skin as compared to conventional gels.