Clinical spectrum of the osmotic-controlled release oral delivery system (OROS), an advanced oral delivery form

In-situ monitoring of in vitro drug release processes in tablets using optical coherence tomography

Film-coated modified-release tablets are an important dosage form amenable to targeted, controlled, or delayed drug release in the specific region of the gastrointestinal (GI) tract. Depending on the film composition and interaction with the GI fluid, such coated products can modulate the local bioavailability, systemic absorption, protection as an enteric barrier, etc. Although the interaction of a dosage form with the surrounding dissolution medium is vital for the resulting release behavior, the underlying physicochemical phenomena at the film and core levels occurring during the drug release process have not yet been well described. In this work, we attempted to tackle this limitation by introducing a novel in vitro test based on optical coherence tomography (OCT) that allows an in-situ investigation of the sub-surface processes occurring during the drug release. Using a commercially available tablet based on osmotic-controlled release oral delivery systems (OROS), we demonstrated the performance of the presented prototype in terms of monitoring the membrane thickness and thickness variability, the surface roughness, the core swelling behavior, and the porosity of the core matrix throughout the in vitro drug release process from OROS. The superior spatial (micron scale) and temporal (less than 10 ms between the subsequent tomograms) resolution achieved in the proposed setup provides an improved understanding of the dynamics inside the microstructure at any given time during the dissolution procedure with the previously unattainable resolution, offering new opportunities for the design and testing of patient-centric dosage forms.

Sustained-Release Vildagliptin 100 mg in Type 2 Diabetes Mellitus: A Review

Dipeptidyl peptidase-4 inhibitors (DPP4Is) were introduced into the management of type 2 diabetes mellitus (T2DM) as they are insulinotropic and have no inherent risk of hypoglycemia and no effect on body weight. Currently, 11 drugs in this class are available for the management of diabetes. Although they have a similar mechanism of action, they differ from one other in their binding mechanisms, which influences their therapeutic and pharmacological profiles. Vildagliptin's overall safety and tolerability profile was comparable to placebo throughout clinical studies, and real-world data in a large group of T2DM patients corroborated this finding. Therefore, DPP4Is like vildagliptin is a secure alternative for treating patients with T2DM. Vildagliptin treatment given as a once-daily (QD) 100 mg sustained release (SR) formulation fits the criteria of adherence and compliance. This SR formulation, given once daily has the potential to provide glycemic control like the vildagliptin 50 mg twice-daily (BD) formulation. This comprehensive review discusses the journey of vildagliptin as 50 mg BD therapy as well as 100 mg SR QD therapy.

Leveraging Physiologically Based Modelling to Provide Insights on the Absorption of Paliperidone Extended-Release Formulation under Fed and Fasting Conditions

Paliperidone was approved by the US FDA in 2006 as an extended-release (ER) tablet (Invega^®) for the once-daily treatment of schizophrenia. This osmotic-controlled release oral delivery system (OROS) offers advantages, such as the prevention of plasma concentration fluctuation and reduced dosing frequency. The administration of the ER after a high-fat/high-calorie meal leads to increased maximum plasma concentration and area under the curve values by 60% and 54%, respectively. Food has various effects on gastrointestinal (GI) physiology, including changed transit times, changed volumes, altered pH in different GI compartments, secretion of bile salts, and increased hepatic blood flow. This may affect solubility, the dissolution rate, absorption, and the pharmacokinetics. The aim of this study was to apply physiologically based absorption modeling (PBAM) to provide insights on paliperidone ER absorption under fed and fasting conditions. The PBAM adequately predicted absorption from the OROS formulation under both conditions. Absorption primarily occurs in the ascending colon and caecum. After a high-fat/high-calorie meal, absorption is increased through the jejunum, ileum, and colon due to either increased solubilization or the better efficiency of the OROS technology. PBAM-guided approaches can improve the understanding of branded drugs and thereby aid in guiding the development of generic formulations or formulation alternatives.

Comparative efficacy of generic nifedipine versus brand-name amlodipine for hypertension management in Taiwan

The control rate of hypertension remains concerning, indicating the requirement for better management strategies. The calcium channel blockers brand‐name amlodipine and nifedipine with extended‐release formulations demonstrate similar clinical efficacy. However, the efficacy of generic nifedipine remains obscure. We compared the efficacy of generic nifedipine and brand‐name amlodipine in terms of cardiovascular (CV) outcomes. Patients prescribed generic nifedipine (SRFC CYH) or brand‐name amlodipine besylate (Norvasc, Pfizer) between August 1, 2017, and July 31, 2018, were enrolled; patients with CV events within 3 months were excluded. CV outcomes included CV death, nonfatal myocardial infarction (MI), nonfatal ischemic stroke, hospitalization for heart failure, and composite endpoints of 3P‐ and 4P‐major adverse cardiac events (MACE). A total of 1625 patients treated with nifedipine (SRFC CYH) and 16 587 patients treated with Norvasc were included. After propensity score matching, there were 995 and 4975 patients in the nifedipine CYH and Norvasc groups, respectively. At a mean follow‐up period of 30.3 ± 6.4 months, nifedipine CYH was comparable to Norvasc in terms of CV death (P = .107), nonfatal MI (P = .121), nonfatal ischemic stroke (P = .453), hospitalization for heart failure (P = .330), 3P‐MACE (P = .584), and 4P‐MACE (P = .274). Cox regression analysis revealed that nifedipine CYH and Norvasc had similar efficacy in terms of 3P‐MACE (hazard ratio, 0.970; 95% confidence interval, 0.601–1.565, P = .900) and 4P‐MACE (hazard ratio, 0.880; 95% confidence interval, 0.628–1.233, P = .459). In conclusion, Nifedipine SRFC CYH and Norvasc have comparable clinical efficacy for hypertension management.

Comparative effectiveness of generic nifedipine versus Adalat long-acting nifedipine for hypertension treatment: A multi-institutional cohort study

This retrospective multi‐institutional database analysis aimed to evaluate the blood‐pressure‐lowering efficacy and clinical outcomes of a generic versus brand‐name nifedipine for hypertension management. A total of 12 693 patients who were prescribed a generic or brand‐name nifedipine between January 1, 2011, and December 31, 2018, were identified from the Chang Gung Research Database of Chang Gung Memorial Hospitals, Taiwan. Among them, 2112 (21.4%) were prescribed generic nifedipine. After propensity score matching, both the generic and brand‐name groups consisted of 2102 patients. At a mean follow‐up of 3 years, the changes in office systolic (p for interaction = .791) and diastolic blood pressure (p for interaction = .689) did not differ significantly between the patients who received the generic and the brand‐name nifedipine. There was no significant difference between the two study groups regarding the composite of all‐cause mortality, acute myocardial infarction, stroke, coronary revascularization, or hospitalization for heart failure (hazard ratio 0.98, 95% confidence interval 0.85–1.13; p = .774). In conclusion, the generic nifedipine was comparable to its brand‐name counterpart regarding office blood pressure reduction and the composite cardiovascular outcome for the treatment of patients with hypertension.

Foundations of gastrointestinal-based drug delivery and future developments

Gastrointestinal-based drug delivery is considered the preferred mode of drug administration owing to its convenience for patients, which improves adherence. However, unique characteristics of the gastrointestinal tract (such as the digestive environment and constraints on transport across the gastrointestinal mucosa) limit the absorption of drugs. As a result, many medications, in particular biologics, still exist only or predominantly in injectable form. In this Review, we examine the fundamentals of gastrointestinal drug delivery to inform clinicians and pharmaceutical scientists. We discuss general principles, including the challenges that need to be overcome for successful drug formulation, and describe the unique features to consider for each gastrointestinal compartment when designing drug formulations for topical and systemic applications. We then discuss emerging technologies that seek to address remaining obstacles to successful gastrointestinal-based drug delivery.

Elastic Bioresorbable Polymeric Capsules for Osmosis-Driven Delayed Burst Delivery of Vaccines

Single-administration vaccine delivery systems are intended to improve the efficiency and efficacy of immunisation programs in both human and veterinary medicine. In this work, an osmotically triggered delayed delivery device was developed that was able to release a payload after a delay of approximately 21 days, in a consistent and reproducible manner. The device was constructed out of a flexible poly(ε-caprolactone) photo-cured network fabricated into a hollow tubular shape, which expelled approximately 10% of its total payload within 2 days after bursting. Characterisation of the factors that control the delay of release demonstrated that it was advantageous to adjust material permeability and device wall thickness over manipulation of the osmogent concentration in order to maintain reproducibility in burst delay times. The photo-cured poly(ε-caprolactone) network was shown to be fully degradable in vitro, and there was no evidence of cytotoxicity after 11 days of direct contact with primary dermal fibroblasts. This study provides strong evidence to support further development of flexible biomaterials with the aim of continuing improvement of the device burst characteristics in order to provide the greatest chance of the devices succeeding with in vivo vaccine booster delivery.

Drug Disposition in the Lower Gastrointestinal Tract: Targeting and Monitoring

The increasing prevalence of colonic diseases calls for a better understanding of the various colonic drug absorption barriers of colon-targeted formulations, and for reliable in vitro tools that accurately predict local drug disposition. In vivo relevant incubation conditions have been shown to better capture the composition of the limited colonic fluid and have resulted in relevant degradation and dissolution kinetics of drugs and formulations. Furthermore, drug hurdles such as efflux transporters and metabolising enzymes, and the presence of mucus and microbiome are slowly integrated into drug stability- and permeation assays. Traditionally, the well characterized Caco-2 cell line and the Ussing chamber technique are used to assess the absorption characteristics of small drug molecules. Recently, various stem cell-derived intestinal systems have emerged, closely mimicking epithelial physiology. Models that can assess microbiome-mediated drug metabolism or enable coculturing of gut microbiome with epithelial cells are also increasingly explored. Here we provide a comprehensive overview of the colonic physiology in relation to drug absorption, and review colon-targeting formulation strategies and in vitro tools to characterize colonic drug disposition.

Pharmacokinetics of exogenous melatonin in relation to formulation, and effects on sleep: A systematic review

There is conflicting evidence on the clinical efficacy of exogenous melatonin for the treatment of sleep disorders. This may be due to differences in the pharmacokinetic (PK) properties of melatonin formulations used in clinical trials. The aim of this systematic review was to understand the relationship between melatonin formulations and PK parameters and, where possible, the effects on sleep outcomes. To this purpose, we conducted a systematic review and nineteen papers were included. The studies included three melatonin transdermal formulation, thirteen oral formulations, one topical, two buccal, two intravenous and two nasogastric formulations. Seven studies investigated the effect of the melatonin formulation on sleep and six of them found a significant improvement in one or more sleep parameters. The potential for an improved controlled release formulation that delays maximum concentration (C_max) was identified. The different formulations and doses affect melatonin PK, suggesting that treatment efficacy maybe affected. Based on the current evidence, we are unable to provide recommendations of specific melatonin formulations and PK parameters for specific sleep disorders. Future studies should systematically investigate how different PK parameters of melatonin formulations affect efficacy treatment of sleep as well as circadian disorders.

Modulating target engagement of small molecules via drug delivery: approaches and applications in drug discovery and development

Drug-delivery technologies for modified drug release have been in existence for decades, but their utilization has been largely limited to post-launch efforts improving therapeutic outcomes. Recently, they have gained renewed importance because the pharmaceutical industry is steadily shifting to a more integrated discovery-development approach. In discovery, modulating target engagement via drug-delivery technologies can enable crucial pharmacological studies for building well-defined criteria for molecular design. In development, earlier implementation of delivery technologies can enhance the value of drug products through reduced dosing frequency and improved tolerability and/or safety profile, thereby leading to better adherence and therapeutic effectiveness.

Efficacy and safety outcomes of one generic nifedipine versus ADALAT long-acting nifedipine for hypertension management

Data regarding the long-term outcomes of generic antihypertensive drugs are limited. This nationwide retrospective database analysis aimed to evaluate the efficacy and safety of a generic versus brand-name nifedipine for hypertension treatment. Patients who were prescribed generic or brand-name nifedipine between January 1, 2008, and December 31, 2013, were identified from the National Health Insurance Research Database of Taiwan. The efficacy outcomes included all-cause mortality and the composite cardiovascular (CV) outcome, including CV death, non-fatal myocardial infarction, non-fatal stroke, coronary revascularization, and hospitalization for heart failure. Safety outcomes included headache, peripheral edema, constipation, acute kidney injury, hypotension, syncope, new diagnosis of cancer, and cancer death. Among the 98 335 patients who were eligible for analysis, 21 087 (21.4%) were prescribed generic nifedipine. Both the generic and the brand-name groups included 21 087 patients after propensity score matching. At a mean follow-up of 4.1 years, the generic nifedipine was comparable to the brand-name drug with regard to all-cause mortality (7.2% vs. 7.1%; hazard ratio [HR] 1.02, 95% confidence interval [CI] 0.95-1.09) and the composite CV outcomes (11.6% vs. 11.9%; HR 0.97; 95% CI 0.92-1.03). The generic nifedipine was associated with higher rates of headache, peripheral edema, and constipation but a modest reduction in the risk of newly diagnosed cancer (7.1% vs. 7.8%; subdistribution HR 0.90, 95% CI 0.84-0.97). The risks of acute kidney injury, hypotension, syncope, and cancer death were not significantly different between the two groups. In conclusion, the generic nifedipine was comparable to the brand-name drug with regard to the risks of all-cause mortality and the composite CV outcome. The finding of cancer risk could be chance and should be interpreted with caution.

Randomized Controlled Trial of Paliperidone Extended Release Versus Risperidone for the Treatment of Methamphetamine-Associated Psychosis in Chinese Patients

BACKGROUND

The efficacy or tolerability of paliperidone extended release (ER) in the treatment of methamphetamine (METH)-associated psychosis (MAP) is unknown. This study was designed to assess the tolerability and efficacy of paliperidone ER and risperidone for the treatment of MAP in China.

METHODS

This 25-day randomized clinical trial involved 120 patients with acute MAP symptoms who were randomized to receive either paliperidone ER or risperidone from baseline to day 25 of an inpatient hospital stay. The primary outcome was changes in the severity of psychosis, which were assessed using the Positive and Negative Syndrome Scale (PANSS) total score changes from baseline to endpoint.

RESULTS

Overall, 84% of the patients completed the entire study protocol. The PANSS total score, the Clinical Global Impressions-Severity of Illness scale (CGI-S) score, and a METH craving score assessed by a visual analog scale (VAS) showed statistically significant improvements from baseline for the patients in both groups (p < 0.01). The Simpson-Angus Scale (SAS) and the Barnes Akathisia Rating Scale (BARS) scores increased from baseline during treatment in both groups (p < 0.01); there were statistically significant differences between the treatment groups in the SAS scores (p < 0.01). Measures of hypermyotonia, salivation, and dizziness were significantly higher in the risperidone-treated patients than in the paliperidone ER-treated patients (all p < 0.05).

CONCLUSION

Paliperidone ER and risperidone had similar efficacy and were generally tolerable in the treatment of MAP; however, paliperidone ER had a more favorable adverse event profile than risperidone, particularly regarding extrapyramidal and prolactin-increasing effects.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier NCT01822730. Full date of first registration:03/28/2013.

Thermoresponsive gating membranes embedded with liquid crystal(s) for pulsatile transdermal drug delivery: An overview and perspectives

Due to the circadian rhythm regulation of almost every biological process in the human body, physiological and biochemical conditions vary considerably over the course of a 24-h period. Thus, optimal drug delivery and therapy should be effectively controlled to achieve the desired therapeutic plasma concentrations and therapeutic drug responses at the required time according to chronopharmacological concepts, rather than continuous maintenance of constant drug concentrations for an extended time period. For many drugs, it is not always necessary to constantly deliver a drug into the human body under disease conditions due to rhythmic variations. Pulsatile drug delivery systems (PDDSs) have been receiving more attention in pharmaceutical development by providing a predetermined lag period, followed by a fast or rate-controlled drug release after application. PDDSs are characterized by a programmed drug release, which may release a drug at repeatable pulses to match the biological and clinical needs of a given disease therapy. This review article focuses on thermoresponsive gating membranes embedded with liquid crystals (LCs) for transdermal drug delivery using PDDS technology. In addition, the principal rationale and the advanced approaches for the use of PDDSs, the marketed products of chronotherapeutic DDSs with pulsatile function designed by various PDDS technologies, pulsatile drug delivery designed with thermoresponsive polymers, challenges and opportunities of transdermal drug delivery, and novel approaches of LC systems for drug delivery are reviewed and discussed. A brief overview of all academic research articles concerning single LC- or binary LC-embedded thermoresponsive membranes with a switchable on-off permeation function through topical application by an external temperature control, which may modulate the dosing interval and administration time according to the therapeutic needs of the human body, is also compiled and presented. In the near future, since thermal-based approaches have become a well-accepted method to enhance transdermal delivery of different water-soluble drugs and macromolecules, a combination of the thermal-assisted approach with thermoresponsive LCs membranes will have the potential to improve PDDS applications but still poses a great challenge.

Transdermal Delivery of Antipsychotics: Rationale and Current Status

The aim of this article is to provide the rationale for the development of transdermal formulations of antipsychotics by highlighting their main advantages, starting with an overview of the antipsychotic formulations that are currently available on the market. Progress regarding transdermal antipsychotic formulations was investigated by performing a search of papers, patents and clinical trials published in the last 10 years. Available data on antipsychotic transdermal formulations are reported and discussed, focusing on the characteristics of the dosage forms and their ability to promote drug absorption. Despite the current availability of a large number of antipsychotics, only a few of these drugs (e.g. aripiprazole, asenapine, blonanserin, chlorpromazine, haloperidol, olanzapine, prochlorperazine, quetiapine, and risperidone) have been developed as transdermal delivery systems. Several papers and patents show that transdermal formulations, such as creams, films, gels, nanosystems, patches, solutions, and sprays, have been evaluated with the aim of expanding the clinical utility of antipsychotic drugs. In particular, the employment of different strategies, such as the use of nanoparticles/vesicles, or permeation enhancers as well as microneedles with iontophoresis, may improve the absorption of antipsychotic drugs through the skin. However, few clinical trials on transdermal delivery of antipsychotic drugs are available and only delivery systems containing asenapine and blonanserin have shown interesting clinical results in terms of pharmacokinetic data, efficacy, and tolerability. Recently, the transdermal patch formulation of blonanserin was approved in Japan for the treatment of schizophrenia.

A Clinician's Guide to Oral Extended-Release Drug Delivery Systems in Epilepsy

Epilepsy is one of the most common chronic neurologic disorders that affects individuals of all ages. It is primarily managed with antiepileptic drugs (AEDs), with the goal of maintaining complete seizure control combined with minimal or no adverse effects. Oral administration is the mainstay of AED delivery for patients with chronic epilepsy and consists essentially of immediate-release (IR) and modified-release (delayed-release and extended-release [ER]) dosage formulations. Extended-release formulations (hydrophilic or hydrophobic matrix systems, reservoir systems, and osmotic-release systems) release a drug in a controlled manner during an extended period of time following administration. Extended-release formulations have many advantages compared with IR formulations, including simplification of dosing regimens, reduction in pill burden, and reduction in the peak-to-trough fluctuations in serum drug concentration that may be associated with a decreased risk of adverse effects and of seizures. These advantages have the potential to increase adherence to antiepileptic therapy, improve the quality of life of patients, and reduce health care costs. This article, which is intended as a practical guide for clinicians, reviews the properties of the different ER AED formulations currently available and discusses the advantages of ER over IR formulations. Subsequently, an explanation of the technologic basis of the different oral ER formulations, the critical attributes that differentiate ER products, and their individual strengths and weaknesses is provided. Specific recommendations to practitioners on treating patients with ER formulations are included.

Controlled Release of the Nimodipine-Loaded Self-Microemulsion Osmotic Pump Capsules: Development and Characterization

The present study was intended to develop a controlled released osmotic pump capsule based on Nimodipine (NM)-loaded self-microemulsifying drug delivery systems (SMEDDSs) in order to improve the low oral bioavailability of NM. To optimize the NM-loaded SMEDDS composition, the experiments of NM solubility in different oils, the pseudo-ternary phase diagram experiments and the different drug loading experiments were conducted in the preliminary screening studies. Controlled release of NM required an osmotic pump capsule comprising a coated semi-permeable capsule shell, plasticizer, and pore-forming agent. NM release follows zero-order kinetics after oral administration. Polyethylene glycol content, used as a pore-forming agent, coating mass, and drug release orifice size were key factors affecting drug release behavior according to the single methods and were optimized through response surface methodology. The NM-loaded SMEDDS droplet size and the ¹H NMR mass spectrogram of the novel capsule were determined. The droplet size of the reconstituted microemulsion was 39.9 nm and ¹H NMR analysis showed NM dissolution in the microemulsion. The dissolution test performed on three batches of NM-SMEDDS capsules-prepared using optimal preparation methods-indicated the capsule to deliver a qualified drug delivery with a zero-order release rate. The results demonstrated that NM-loaded SMEDDSs were successfully developed and displayed a qualified release rate in vitro.

Tablets of paliperidone using compression-coated technology for controlled ascending release

The aim of this work was to prepare ascending release compression-coated (CC) tablets with paliperidone (PAL) using a simple manufacturing technique and short manufacturing process. The release behavior and mechanisms in vitro of the final tablets was investigated and evaluated. The PAL CC tablets were comprised of a core layer of high viscosity hydroxypropyl cellulose (HPC-H) and a coating layer of high viscosity hydroxypropyl methylcellulose (HPMC-K100M). Several factors such as materials and core tablet compositions were studied for their influence in the formulation procedure. The drug release mechanism was studied using gravimetric analysis. The data could be fitted to the Peppas model. The ascending drug release results were expressed in terms of the slope of the release curve at different time points. Results showed that the formulation could achieve a good ascending drug release when the weight ratio of PAL was 5:1 (core:layer). The fraction of HPC and HPMC was 33 %, and the combination of Eudragit RL-PO was 10%. The ascending release mechanism was due to solvent penetration into the PAL CC tablets, and subsequent drug dissolution from the gelatinous HPC and HPMC matrix erosion. The release mechanism was therefore a combination of diffusion and erosion. This work demonstrated that the compression-coated tablets could achieve controlled ascending release over 24 h for the oral administration systems.

Characterization of new functionalized calcium carbonate-polycaprolactone composite material for application in geometry-constrained drug release formulation development

A new mineral-polymer composite (FCC-PCL) performance was assessed to produce complex geometries to aid in development of controlled release tablet formulations. The mechanical characteristics of a developed material such as compactibility, compressibility and elastoplastic deformation were measured. The results and comparative analysis versus other common excipients suggest efficient formation of a complex, stable and impermeable geometries for constrained drug release modifications under compression. The performance of the proposed composite material has been tested by compacting it into a geometrically altered tablet (Tablet-In-Cup, TIC) and the drug release was compared to commercially available product. The TIC device exhibited a uniform surface, showed high physical stability, and showed absence of friability. FCC-PCL composite had good binding properties and good compactibility. It was possible to reveal an enhanced plasticity characteristic of a new material which was not present in the individual components. The presented FCC-PCL composite mixture has the potential to become a successful tool to formulate controlled-release dosage solid forms.

Physiologically Based Pharmacokinetic and Absorption Modeling for Osmotic Pump Products

Physiologically based pharmacokinetic (PBPK) and absorption modeling approaches were employed for oral extended-release (ER) drug products based on an osmotic drug delivery system (osmotic pumps). The purpose was to systemically evaluate the in vivo relevance of in vitro dissolution for this type of formulation. As expected, in vitro dissolution appeared to be generally predictive of in vivo PK profiles, because of the unique feature of this delivery system that the in vitro and in vivo release of osmotic pump drug products is less susceptible to surrounding environment in the gastrointestinal (GI) tract such as pH, hydrodynamic, and food effects. The present study considered BCS (Biopharmaceutics Classification System) class 1, 2, and 3 drug products with half-lives ranging from 2 to greater than 24 h. In some cases, the colonic absorption models needed to be adjusted to account for absorption in the colon. C _max (maximum plasma concentration) and AUCt (area under the concentration curve) of the studied drug products were sensitive to changes in colon permeability and segmental GI transit times in a drug product-dependent manner. While improvement of the methodology is still warranted for more precise prediction (e.g., colonic absorption and dynamic movement in the GI tract), the results from the present study further emphasized the advantage of using PBPK modeling in addressing product-specific questions arising from regulatory review and drug development.

Paliperidone for the treatment of schizophrenia and schizoaffective disorders - a drug safety evaluation

INTRODUCTION

Paliperidone, the major active metabolite of risperidone, is a second-generation antipsychotic that has been developed as an extended-release (ER) oral formulation and a long-acting injectable paliperidone palmitate (PP) formulation. Paliperidone has demonstrated efficacy in the reduction of acute schizophrenia symptoms and clinical benefits were maintained also in the long-term treatments. Paliperidone ER and PP are generally well tolerated with a predictable adverse event profile. Areas covered: Data from studies evaluating safety and tolerability in the acute and maintenance treatment of schizophrenia with paliperidone are reviewed. The reported treatment-emergent adverse events of these formulations are discussed. Expert opinion: In the treatment of schizophrenia and schizoaffective disorders the safety profile has a central role because it can enhance patient compliance. In fact treatment-emergent adverse events are one of the main causes of discontinuation in these patients. In particular the main limitation in the administration of paliperidone could be represented by the onset of hyperprolactinemia (especially in women) and of mild parkinsonism. Paliperidone has a high impact on current long-term drug strategies, especially given the new 3 month long-acting injectable formulation of PP.

Treatment satisfaction with paliperidone extended-release tablets: open-label study in schizophrenia patients dissatisfied with previous antipsychotic medication

OBJECTIVE

The aim of this study was to evaluate the changes in treatment satisfaction after switching to paliperidone extended-release (ER) in Chinese schizophrenia patients dissatisfied with their previous antipsychotic treatment.

METHODS

In this 8-week, open-label, single-arm, multicenter, prospective study, 1,693 patients dissatisfied with previous antipsychotic medication were enrolled and switched to paliperidone ER tablets (3-12 mg/d) based on clinical judgment. The primary efficacy end point was change in Medication Satisfaction Questionnaire (MSQ) score from baseline to week 8. The secondary end points included percentage of patients with MSQ score ≥4, as well as changes in Clinical Global Improvement-Severity (CGI-S) and Personal and Social Performance (PSP) scores.

RESULTS

MSQ scores increased significantly from baseline (mean [standard deviation {SD}]: 2.48 [0.55]) to week 8 (5.47 [0.89], P<0.0001; primary end point, full analysis set). The percentage of patients with MSQ score ≥4 was 95.9% at week 8, indicating that most of the patients were satisfied with their treatment. Significant (P<0.0001) improvements from baseline to week 8 were noted in CGI-S score (2.37 [1.20]) and PSP score (25.5 [15.0]). A total of 174 (10.28%) patients experienced adverse events (AEs). The most common (>10 patients) events were extrapyramidal disorder (n=84, 4.96%), poor quality sleep (n=18, 1.06%) and akathisia (n=13, 0.77%). The majority of AEs were mild to moderate in severity. No deaths occurred.

CONCLUSION

Treatment satisfaction improved after switching to paliperidone ER from the previous antipsychotic in Chinese patients with schizophrenia.

Effect of solvent on retarding the release of diltiazem HCl from Polyox-based liquisolid tablets

Objectives

The aim of this work was to investigate the use of liquisolid technique to sustain the release of a model highly soluble drug, diltiazem HCl, from liquisolid matrices containing Polyox, a recently proposed matrix-forming hydrophilic polymer as an alternative to hypromellose.

Methods

Polyox-based liquisolid formulations prepared using several non-volatile solvents (i.e. polysorbate 80, polyethylene glycol, polyethylene glycol 200 and polyethylene glycol 600) and then characterised using differential scanning calorimetry and powder X-ray diffraction. The influence of solvent on retarding the release of diltiazem HCl from Polyox-based liquisolid tablets compared to conventional physical mixture tablets was studied.

Key findings

Liquisolid tablets exhibited greater retarding properties compared to conventional tablets. The use of polysorbate produced a slower release pattern of the drug from diltiazem hydrochloride (DTZ) liquisolid tablets compared to propylene glycol and polyethylene glycol (200 and 600). The release retardation was decreased with the increase in the concentration of the drug within drug:solvent liquid medication used. Solid-state analysis suggested the presence of a fraction of the drug mass in a solubilised state within polysorbate in liquisolid powders.

Conclusion

Polyox-based matrix tablets prepared using liquisolid technique in the presence of a carefully selected non-volatile solvent could produce desirable, more sustained release profiles of highly water-soluble drugs compared to conventional physical mixture tablets.

Development of a Novel Simplified PBPK Absorption Model to Explain the Higher Relative Bioavailability of the OROS® Formulation of Oxybutynin

A new minimal Segmented Transit and Absorption model (mSAT) model has been recently proposed and combined with intrinsic intestinal effective permeability (P _eff,int ) to predict the regional gastrointestinal (GI) absorption (f _abs ) of several drugs. Herein, this model was extended and applied for the prediction of oral bioavailability and pharmacokinetics of oxybutynin and its enantiomers to provide a mechanistic explanation of the higher relative bioavailability observed for oxybutynin's modified-release OROS® formulation compared to its immediate-release (IR) counterpart. The expansion of the model involved the incorporation of mechanistic equations for the prediction of release, transit, dissolution, permeation and first-pass metabolism. The predicted pharmacokinetics of oxybutynin enantiomers after oral administration for both the IR and OROS® formulations were in close agreement with the observed data. The predicted absolute bioavailability for the IR formulation was within 5% of the observed value, and the model adequately predicted the higher relative bioavailability observed for the OROS® formulation vs. the IR counterpart. From the model predictions, it can be noticed that the higher bioavailability observed for the OROS® formulation was mainly attributable to differences in the intestinal availability (F _G ) rather than due to a higher colonic f _abs , thus confirming previous hypotheses. The predicted f _abs was almost 70% lower for the OROS® formulation compared to the IR formulation, whereas the F _G was almost eightfold higher than in the IR formulation. These results provide further support to the hypothesis of an increased F _G as the main factor responsible for the higher bioavailability of oxybutynin's OROS® formulation vs. the IR.

Efficacy and Tolerability of Paliperidone Extended-release in the Treatment of First-episode Psychosis: An Eight-week, Open-label, Multicenter Trial

Objective

We investigated the efficacy and tolerability of paliperidone extended-release (ER) tablets in patients with first-episode psychosis (n=75).

Methods

This was an 8-week, open-label, multicenter trial. The primary outcome variable was scores on the Positive and Negative Syndrome Scale (PANSS); secondary measures included the Scale for the Assessment of Negative Symptoms (SANS), the Cognitive Assessment Interview (CAI), and the Global Assessment of Functioning (GAF). To assess safety, we measured drug-related adverse events, weight, lipid-related variables, and prolactin and administered the Simpson–Angus Rating Scale (SARS), the Abnormal Involuntary Movement Scale (AIMS), the Barnes Akathisia Scale (BAS), the Arizona Sexual Experiences Scale (ASEX), and the Udvalg for Kliniske Undersogelser side effect rating scale (UKU).

Results

The administration of paliperidone ER resulted in significant improvement in the PANSS, SANS, CAI, and GAF scores (p<0.001) over time. This improvement was evident as early as 1 week. The most frequent adverse events were akathisia, somnolence, anxiety, and sedation, which were well tolerated. Modest increases in weight and lipid profiles were also noted. Prolactin levels were substantially increased at the endpoint in both male and female patients.

Conclusion

These results indicate that paliperidone ER is effective and is characterized by good tolerability in the treatment of positive and negative symptoms and cognitive functioning in first-episode psychosis.

Early predictors of a clinical response at 8 weeks in patients with first-episode psychosis treated with paliperidone ER

Identification of early clinical markers that predict later treatment outcomes in first-episode psychosis is highly valuable. The present study was conducted to determine the best time at which to predict the late treatment response in first-episode psychosis patients treated with paliperidone extended release (ER), the factors predicting early treatment responses (at Week 2 and Week 3) and the relationships between the paliperidone ER plasma concentrations at Week 2 and Week 3, and the treatment responses at Week 2, Week 3 and Week 8. Various criteria for assessing treatment response were employed. We determined the plasma paliperidone concentrations at Week 2 and Week 3, using validated high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS). The treatment response at Week 3 optimally predicted the later (Week 8) response, in terms of negative predictive value (NPV). Independent predictors for good treatment responses at Week 2 and Week 3 were: Female gender, a higher educational level, a higher Positive and Negative Syndrome Scale (PANSS) excited score, and/or a shorter duration of untreated psychosis (DUP). The plasma paliperidone concentration at Week 3, but not Week 2, was a significant predictor of the late treatment response at Week 8. These results may help appropriate clinical decision-making for early non-responders after having their first episode of psychosis.

Synchronized and controlled release of metformin hydrochloride/glipizide from elementary osmotic delivery

The combination of metformin hydrochloride (MTF) and glipizide (GLZ) is second-line medication for diabetes mellitus type 2 (DMT2). In the present study, elementary osmotic pump ( EOP) tablet is designed to deliver the combination of MTF and GLZ in a sustained and synchronized manner. By analyzing different variables of the formulation, sodium hydrogen carbonate is introduced as pH modifier to improve the release of GLZ, while ethyl cellulose acts as release retardant to reduce the burst release phase of MTF. A two-factor, three-level face-centered central composite design (FCCD) is applied to investigate the impact of different factors on drug release profile. Compared with conventional tablets, the EOP tablet demonstrates a controlled release behavior with relative bioavailability of 99.2% for MTF and 99.3% for GLZ. Data also shows EOP tablet is able to release MTF and GLZ in a synchronized and sustained manner both in vitro and in vivo.

Response Surface Analysis and Nonlinear Optimization Algorithm for Maximization of Clinical Drug Performance: Application to Extended-Release and Long-Acting Injectable Paliperidone

Model-based approach is recognized as a tool to make drug development more productive and to better support regulatory and therapeutic decisions. The objective of this study was to develop a novel model-based methodology based on the response surface analysis and a nonlinear optimizer algorithm to maximize the clinical performances of drug treatments. The treatment response was described using a drug-disease model accounting for multiple components such as the dosage regimen, the pharmacokinetic characteristics of a drug (including the mechanism and the rate of drug delivery), and the exposure-response relationship. Then, the clinical benefit of a treatment was defined as a function of the diseases and the clinical endpoints and was estimated as a function of the target pharmacodynamic endpoints used to evaluate the treatment effect. A case study is presented to illustrate how the treatment performances of paliperidone extended release (ER) and paliperidone long-acting injectable (LAI) can be improved. A convolution-based approach was used to characterize the pharmacokinetics of ER and LAI paliperidone. The drug delivery properties and the dosage regimen maximizing the clinical benefit (defined as the target level of D2 receptor occupancy) were estimated using a nonlinear optimizer. The results of the analysis indicated that a substantial improvement in clinical benefit (from 15% to 27% for the optimization of the in vivo release and from ∼30% to ∼70% for the optimization of dosage regimen) was obtained when optimal strategies were deployed either for optimizing the in vivo drug delivery properties of ER formulations or for optimizing the dosage regimen of LAI formulations.

A novel asymmetric membrane osmotic pump capsule with in situ formed delivery orifices for controlled release of gliclazide solid dispersion system

In this study, a novel asymmetric membrane osmotic pump capsule of gliclazide (GLC) solid dispersion was developed to achieve a controlled drug release. The capsule shells were obtained by wet phase inversion process using cellulose acetate as semi-permeable membrane, glycerol and kolliphor P188 as pore formers, then filled with the mixture of GLC solid dispersion and pH modifiers. Differentiate from the conventional formulations, sodium carbonate was chosen as the osmotic agent and effervescent agent simultaneously to control the drug release, instead of the polymer materials. The ternary solid dispersion of GLC, with polyethylene glycol 6000 and kolliphor P188 as carriers, was prepared by solvent-evaporation method, realizing a 2.09-fold increment in solubility and dissolution rate in comparison with unprocessed GLC. Influence of the composition of the coating solution and pH modifiers on the drug release from the asymmetric membrane capsule (AMC) was investigated. The ultimate cumulative release of the optimal formulation reached 91.32% in an approximately zero-order manner. The osmotic pressure test and dye test were conducted to validate the drug release mechanism from the AMC. The in vivo pharmacokinetic study of the AMC indicated a 102.66±10.95% relative bioavailability compared with the commercial tablet, suggesting the bioequivalence between the two formulations. Consequently, the novel controlled delivery system with combination of solid dispersion and AMC system is capable of providing a satisfactory alternative to release the water-insoluble drugs in a controlled manner.

Drug loaded and ethylcellulose coated mesoporous silica for controlled drug release prepared using a pilot scale fluid bed system

The goal of this study was to test the feasibility to load non-ordered, non-spherical mesoporous silica with the model drug paracetamol, and subsequently coat the loaded particles using one single pilot scale fluid bed system equipped with a Wurster insert. Mesoporous silica particles (Davisil(®)) with a size ranging from 310 to 500μm and an average pore diameter of 15nm were loaded with paracetamol to 18.8% drug content. Subsequently, loaded cores were coated with ethylcellulose to obtain controlled drug release. Coating processing variables were varied following a full factorial design and their effect on drug release was assessed. Increasing coating solution feed rate and decreasing fluidizing air temperature were found to increase drug release rates. Increasing pore former level and decreasing coating level were found to increase drug release rates. The release medium's osmolality was varied using different sodium chloride concentrations, which was found to affect drug release rates. The results of this study clearly indicate the potential of non-ordered, non-spherical mesoporous silica as a reservoir carrier for the controlled release of drugs. Although non-spherical, we were able to reproducibly coat this carrier using a bottom spray fluid bed system. However, a major hurdle that needs to be tackled is the attrition the material suffers from during fluid bed processing.

A Flexible-Dose Study of Paliperidone ER in Patients With Nonacute Schizophrenia Previously Treated Unsuccessfully With Oral Olanzapine

OBJECTIVE

The goal of this study was to explore the tolerability, safety, and treatment response of switching from oral olanzapine to paliperidone extended release (ER).

METHODS

Adult patients with nonacute schizophrenia who had been treated unsuccessfully with oral olanzapine were switched to flexible doses of paliperidone ER (3 to 12 mg/d). The primary efficacy outcome was a ≥ 20% improvement in Positive and Negative Syndrome Scale (PANSS) total scores from baseline to endpoint for patients who switched medications because of lack of efficacy with olanzapine and noninferiority versus previous olanzapine treatment (mean endpoint change in PANSS total scores vs. baseline of ≤ 5 points) for patients who switched for reasons other than lack of efficacy. Safety and tolerability were assessed by monitoring adverse events, extrapyramidal symptoms, and weight change.

RESULTS

Of 396 patients, 65.2% were men, mean age was 40.0 ± 12.0 years, and 75.5% had paranoid schizophrenia. Among the patients whose main reason for switching was lack of efficacy, an improvement in the PANSS total score of ≥ 20% occurred in 57.4% of patients. Noninferiority was confirmed for each subgroup of patients whose main reason for switching was something other than lack of efficacy. Paliperidone ER was generally well tolerated. Extrapyramidal symptoms as measured by total Extrapyramidal Symptom Rating Scale scores showed statistically significant and clinically relevant improvements at endpoint, the average weight decreased by 0.8 ± 5.2 kg at endpoint, and a clinically relevant weight gain of ≥ 7% occurred in 8.0% of patients.

CONCLUSION

Paliperidone ER flexibly-dosed over 6 months was well tolerated and associated with a meaningful clinical response in patients with nonacute schizophrenia who had previously been unsuccessfully treated with oral olanzapine.

Critical evaluation of paliperidone in the treatment of schizophrenia in Chinese patients: a systematic literature review

BACKGROUND

Paliperidone (9-hydroxyrisperidone), the major active metabolite of risperidone, has been introduced as a novel atypical antipsychotic agent in many countries. It is available both as an oral extended-release (ER) formulation and as a long-acting injection (paliperidone palmitate, PP), which have been approved for treating schizophrenia in the People's Republic of China since 2009 and 2012, respectively. This systematic review summarizes the efficacy, effectiveness, and safety of paliperidone in the treatment of schizophrenia in the Chinese population.

METHODS

A systematic literature search was conducted on the databases covering international and Chinese core journals, published from January 1, 2008, to May 22, 2015.

RESULTS

A total of 122 publications were retrieved, of which 63 studies were identified for inclusion; most studies were related to paliperidone ER (n=53), nine were related to PP, and one study was related to both agents. Paliperidone ER demonstrated at least comparable efficacy with active comparators, including risperidone, olanzapine, ziprasidone, or aripiprazole, and was found to be superior with respect to the onset of action and improvement in the Personal and Social Performance Scale score. Paliperidone ER appeared to be associated with a lower risk of metabolic syndromes; the most common treatment-emergent adverse events were extrapyramidal symptoms, akathisia, insomnia, and somnolence. Results from interventional and observational studies showed that PP was also an effective and well-tolerated treatment for Chinese patients with schizophrenia. The findings were generally consistent with those observed in non-Chinese populations.

CONCLUSION

Both paliperidone ER and PP were effective and well-tolerated agents for the treatment of schizophrenia in the Chinese population according to the data we reviewed. No new safety signals specific for the Chinese population were raised for paliperidone. Further studies may be needed to collect more data on long-term treatment of schizophrenia in the People's Republic of China.

Treatment response, safety, and tolerability of paliperidone extended release treatment in patients recently diagnosed with schizophrenia

OBJECTIVE

This study was designed to explore the efficacy and tolerability of oral paliperidone extended release (ER) in a sample of patients who were switched to flexible doses within the crucial first 5 years after receiving a diagnosis of schizophrenia.

METHODS

Patients were recruited from 23 countries. Adults with nonacute but symptomatic schizophrenia, previously unsuccessfully treated with other oral antipsychotics, were transitioned to paliperidone ER (3-12 mg/day) and prospectively treated for up to 6 months. The primary efficacy outcome for patients switching for the main reason of lack of efficacy with their previous antipsychotic was at least 20% improvement in Positive and Negative Syndrome Scale (PANSS) total scores. For patients switching for other main reasons, such as lack of tolerability, compliance or 'other', the primary outcome was non-inferiority in efficacy compared with the previous oral antipsychotic.

RESULTS

For patients switching for the main reason of lack of efficacy, 63.1% achieved an improvement of at least 20% in PANSS total scores from baseline to endpoint. For each reason for switching other than lack of efficacy, efficacy maintenance after switching to paliperidone ER was confirmed. Statistically significant improvement in patient functioning from baseline to endpoint, as assessed by the Personal and Social Performance scale, was observed (p < 0.0001). Treatment satisfaction with prior antipsychotic treatment at baseline was rated 'good' to 'very good' by 16.8% of patients, and at endpoint by 66.0% of patients treated with paliperidone ER. Paliperidone ER was generally well tolerated, with frequently reported treatment-emergent adverse events being insomnia, anxiety and somnolence.

CONCLUSIONS

Flexibly dosed paliperidone ER was associated with clinically relevant symptomatic and functional improvement in recently diagnosed patients with non-acute schizophrenia previously unsuccessfully treated with other oral antipsychotics.

Initial design and physical characterization of a polymeric device for osmosis-driven delayed burst delivery of vaccines

Achieving the combination of delayed and immediate release of a vaccine from a delivery device without applying external triggers remains elusive in implementing single administration vaccination strategies. Here a means of vaccine delivery is presented, which exploits osmosis to trigger delayed burst release of an active compound. Poly(ε-caprolactone) capsules of 2 mm diameter were prepared by dip-coating, and their burst pressure and release characteristics were evaluated. Burst pressures (in bar) increased with wall thickness (t in mm) following Pburst  = 131(.) t + 3(.) 4 (R(2)  = 0.93). Upon immersion in PBS, glucose solution-filled capsules burst after 8.7 ± 2.9 days. Copolymers of hydrophobic ε -caprolactone and hydrophilic polyethylene glycol were synthesized and their physico-chemical properties were assessed. With increasing hydrophilic content, the copolymer capsules showed increased water uptake rates and maximum weight increase, while the burst release was earlier: 5.6 ± 2.0 days and 1.9 ± 0.2 days for 5 and 10 wt% polyethylene glycol, respectively. The presented approach enables the reproducible preparation of capsules with high versatility in materials and properties, while these vaccine delivery vehicles can be prepared separately from, and independently of the active compound.

Paliperidone extended-release tablets in Chinese patients with schizophrenia: meta-analysis of randomized controlled trials

BACKGROUND

Previous meta-analyses have compared paliperidone extended-release (ER) tablets with other antipsychotics, but none have involved Chinese patients or studies from People's Republic of China. Further, the results of these meta-analyses may not be applicable to Chinese patients. In the present study, we evaluated the efficacy, safety, and acceptability of paliperidone ER compared with other second-generation antipsychotics (SGAs) for Chinese patients with schizophrenia.

METHODS

Randomized controlled studies of paliperidone ER and other SGAs as oral monotherapy in the acute phase treatment of schizophrenia were retrieved from Medline, Embase, and the Cochrane Library (CENTRAL), as well as from Chinese databases including the China National Knowledge Infrastructure, Wanfang, and VIP Information/Chinese Scientific Journals Database. We pooled data on response rates, chance of withdrawal due to adverse events, probability of adverse events, and odds of withdrawal for any reason.

RESULTS

Fifty randomized controlled trials were identified. The response rate for paliperidone ER was significantly higher than that of other pooled SGAs (risk ratio [RR] 0.83, 95% confidence interval [CI] 0.72-0.96) and ziprasidone (RR 0.57, 95% CI 0.39-0.82). Paliperidone ER significantly reduced the chance of withdrawal due to adverse events and the chance of any adverse events compared with other pooled SGAs (RR 0.32, 95% CI 0.17-0.58 and RR 0.88, 95% CI 0.79-0.97) and risperidone (RR 0.31, 95% CI 0.14-0.67 and RR 0.70, 95% CI 0.57-0.86). The incidence of extrapyramidal symptoms on paliperidone ER was comparable with other pooled SGAs (RR 0.94, 95% CI 0.66-1.35) and significantly lower than that of risperidone (RR 0.56, 0.41-0.77) but higher than that of olanzapine (RR 1.88, 95% CI 1.05-3.36). Paliperidone ER was superior to other pooled SGAs (RR 0.32, 95% CI 0.21-0.49 and RR 0.50, 95% CI 0.35-0.72) and olanzapine (RR 0.23, 95% CI 0.15-0.33 and RR 0.33, 95% CI 0.23-0.47) as far as weight gain and somnolence were concerned. Further, prolactin-related adverse events caused by paliperidone ER were comparable with other pooled SGAs (RR 1.30, 95% CI 0.73-2.33), but outnumbered those caused by olanzapine (RR 7.53, 95% CI 2.05-27.71).

CONCLUSION

Paliperidone ER is efficacious, safe, and well accepted when compared with other pooled SGAs for the treatment of Chinese patients with schizophrenia.

Curse of the ghost pills: the role of oral controlled-release formulations in the passage of empty intact shells in faeces. Two case reports and a literature review relevant to psychiatry

Orally taken tablets in different formulations continue to have a central role in the treatment of various psychiatric and medical conditions. In order to improve compliance, reduce the frequency of taking medications and minimize the peaks and troughs associated with certain immediate-release formulations, pharmaceutical companies have developed a number of novel methods of delivering oral solid dosage medications in the form of controlled-release (CR) formulations. Some CR formulations have been associated with pharmacobezoars and false-positive findings on certain physical investigations. Though CR drugs are commonly used in psychiatry, clinicians appear to have a limited understanding of how they are released for absorption once ingested. Some have insoluble parts that are excreted in faeces as 'ghost pills'. Due to lack of awareness of this phenomenon to both patients and the physicians, anxiety has ensued in some patients. Some clinicians have been puzzled or have been dismissive when faced with curious patients wanting to know more after they had observed tablet-like looking structures in faeces. We present two cases from our clinical setting and a few drawn from the World Wide Web to highlight the role of CR medications and their association with the ghost pill phenomenon. The mechanisms involved in drug release relevant to psychiatry medications are also briefly reviewed. The ghost pill phenomenon occurs with certain CR medications. This is a normal and expected outcome related to drug-release mechanisms of some of these products. It is inevitable that some patients will see what looks like tablets or capsules in faeces. Raising awareness of this phenomenon among clinicians would facilitate discussions and information sharing at the initial process of medication prescribing. Awareness among patients and carers would also help to allay anxiety.

Dosing and switching of paliperidone ER in patients with schizophrenia: recommendations for clinical practice

Many patients with schizophrenia receive long-term treatment with antipsychotic medication. Switching of antipsychotic medication due to lack of efficacy, tolerability issues, and partial/non-adherence is common. Despite this, consensus strategies for switching between antipsychotics are lacking. This manuscript provides practical recommendations for switching antipsychotic medication to ensure optimal management of patients with schizophrenia, with a particular focus on paliperidone extended release (ER). The authors drew on their clinical experience supported by detailed discussion of literature describing antipsychotic switching techniques and strategies and findings from paliperidone ER clinical trials. Antipsychotic switching strategies should be individualized and take into consideration the pharmacokinetic (PK) and pharmacodynamic (PD) properties of the pre- and post-switch medication. The use of temporary concomitant medications may be appropriate in some scenarios. Abrupt withdrawal of pre-switch medication may be appropriate in some instances but carries a greater risk of rebound and withdrawal symptoms than other strategies. Cross-tapering is the method most widely used in clinical practice. Paliperidone ER can be initiated without dose titration. The EU SmPC recommended dose of paliperidone ER is 6 mg/day; but doses should be individualized within the approved range of 3-12 mg/day. Higher doses may be required due to insufficient efficacy of the previous antipsychotic or in patients with acute symptoms. Recently diagnosed patients, those with renal impairment, or patients who have previously experienced tolerability issues with other antipsychotics may require lower doses. When switching from risperidone, higher doses of paliperidone ER may be required compared with risperidone. When switching from antipsychotics that have sedative and/or significant anticholinergic activity, the pre-switch antipsychotic should be tapered off gradually. Antipsychotics with less sedating and little anticholinergic activity can be tapered off over a shorter period. Temporary concomitant sedative medication may be beneficial when switching from antipsychotics with relatively higher sedative propensities. Switching from another antipsychotic to paliperidone ER requires individualized switching strategies and dosing, dependent on the characteristics of the patient and the PK and PD properties of the pre-switch medication. Cross-tapering strategies should be considered as a means of reducing the risk of rebound and withdrawal symptoms.

Paliperidone extended-release in patients with non-acute schizophrenia previously unsuccessfully treated with other oral antipsychotics

OBJECTIVE

This study explores relevant outcomes with flexibly dosed paliperidone extended-release (ER) in a real-world design.

RESEARCH DESIGN AND METHODS

Patients were recruited from 23 countries. Adults with non-acute schizophrenia (n = 1812), previously unsuccessfully treated with other oral antipsychotics, were transitioned to paliperidone ER and prospectively treated for 6 months.

MAIN OUTCOME MEASURES

Primary efficacy outcome for patients switching for the main reason of lack of efficacy was ≥ 20% improvement in Positive and Negative Syndrome Scale (PANSS) total scores. For patients switching for main reasons other than lack of efficacy, primary outcome was non-inferiority in efficacy compared with the previous medication.

RESULTS

Among the lack-of-efficacy group, 61% achieved a ≥ 20% improvement in PANSS total scores from baseline to endpoint. For switchers from other than the lack-of-efficacy group, efficacy maintenance after switching to paliperidone ER was confirmed. Clinically relevant and statistically significant symptomatic improvements occurred for each patient group based on main reason for switching.

CONCLUSION

Paliperidone ER was well tolerated and associated with a meaningful clinical response in patients who switched from other oral antipsychotics, with insomnia and anxiety as most frequent side-effects.

Hydromorphone: evolving to meet the challenges of today's health care environment

BACKGROUND

Hydromorphone, a potent analogue of morphine, has long had an important role in pain management and is included in several international guidelines for managing pain. Advances in hydromorphone formulations and the ways in which hydromorphone is being used clinically today warrant a review of the drug's pharmacotherapeutic utility.

OBJECTIVE

The history and recent advances in hydromorphone pharmacotherapy are reviewed. Areas covered include the pharmacologic and metabolic profile of hydromorphone, the role of hydromorphone in pain management, formulations and routes of administration, and issues related to relative opioid potencies, equianalgesic ratios, and opioid rotation. Because hydromorphone, like all opioids, carries a risk of misuse, abuse, and illicit diversion, the related issues of tamper-resistant formulations and "dose-dumping" of extended-release formulations are discussed.

CONCLUSIONS

Due to the epidemic of prescription opioid overdoses associated with prescription opioid abuse in the United States, development of tamper-resistant opioid formulations that avoid dose-dumping issues has become a significant goal of pharmaceutical manufacturers. The current formulation of hydromorphone extended-release potentially provides the benefits of long-acting hydromorphone (ie, continuous pain control, increased quality of life, freedom to perform daily activities) to appropriate patients, while reducing the risks of abuse and without compromising safety.