Miniaturized screening and performance prediction of tailored subcutaneous extended-release formulations for preclinical in vivo studies

Microencapsulation of active pharmaceutical ingredients (APIs) for preparation of long acting injectable (LAI) formulations is an auspicious technique to enable preclinical characterization of a broad variety of APIs, ideally independent of their physicochemical and pharmacokinetic (PK) characteristics. During early API discovery, tunable LAI formulations may enable pharmacological proof-of-concept for the given variety of candidates by tailoring the level of plasma exposure over the duration of various timespans. Although numerous reports on small scale preparation methods for LAIs utilizing copolymers of lactic and glycolic acid (PLGA) and polymers of lactic acid (PLA) highlight their potential, application in formulation screening and use in preclinical in vivo studies is yet very limited. Transfer from downscale formulation preparation to in vivo experiments is hampered in early preclinical API screening by the large number of API candidates with simultaneously very limited available amount in the lower sub-gram scale, lack of formulation stability and deficient tunability of sustained release. We hereby present a novel comprehensive platform tool for tailored extended-release formulations, aiming to support a variety of preclinical in vivo experiments with ranging required plasma exposure levels and timespans. A novel small-scale spray drying process was successfully implemented by using an air brush based instrument for preparation of PLGA and PLA based formulations. Using Design of Experiments (DoE), required API amount of 250 mg was demonstrated to suffice for identification of dominant polymer characteristics with largest impact on sustained release capability for an individual API. BI-3231, a hydrophilic and weakly acidic small compound with good water solubility and permeability, but low metabolic stability, was used as an exemplary model for one of the many candidates during API discovery. Furthermore, an in vitro to in vivo correlation (IVIVC) of API release rate was established in mice, which enabled the prediction of in vivo plasma concentration plateaus after single subcutaneous injection, using only in vitro dissolution profiles of screened formulations. By tailoring LAI formulations and their doses for acute and sub-chronic preclinical experiments, we exemplary demonstrate the practical use for BI-3231. Pharmacological proof-of-concept could be enabled whilst circumventing the need of multiple administration as result of extensive hepatic metabolism and simultaneously superseding numerous in vivo experiments for formulation tailoring.

Lacosamide extended-release capsules are bioequivalent to lacosamide immediate-release tablets: Pharmacokinetic observations and simulations

OBJECTIVES

Assess the bioequivalence of lacosamide extended-release (XR) capsules and immediate-release (IR) tablets and answer real-world clinical questions regarding the use of lacosamide XR.

METHODS

An open-label, randomized, two-treatment, two-sequence, oral comparative bioavailability study was conducted to assess the bioequivalence of two lacosamide formulations. Participants were randomized 1:1 to receive lacosamide XR capsules (400 mg once-daily) or IR tablets (200 mg twice-daily) in 1 of 2 sequences over 7-day periods. Primary outcome was the area under the lacosamide concentration-time curve over 24 h at steady-state (AUC0-τ,ss). Secondary outcomes were maximum (Cmax,ss) and minimum concentrations at steady-state (Cmin,ss). Bioequivalence was established when 90% confidence intervals (CIs) for geometric least square means ratios (GLSMs) were between 80% and 125%. Adverse events (AEs) and other safety outcomes were also assessed. Pharmacokinetic simulations, including adherent and partially adherent dosing scenarios with XR and IR formulations, modeled the clinical use of lacosamide XR.

RESULTS

Thirty-five healthy adult males were enrolled in the bioequivalence study. After 7 days of study drug, mean AUC0-τ,ss, Cmax,ss, and Cmin,ss values were similar between XR and IR formulations; all 90% CIs for GLSMs were between 80% and 125%. AEs were mild and no serious AEs or other clinically significant safety findings were observed. Pharmacokinetic simulations suggested that partial adherence affected formulations similarly; and the best strategy for switching formulations was to take the morning lacosamide IR dose followed by the evening lacosamide XR dose, as this resulted in the most consistent lacosamide plasma concentrations.

CONCLUSIONS

Once-daily lacosamide XR capsules were bioequivalent to twice-daily lacosamide IR tablets. Pharmacokinetic simulations indicated lacosamide XR and IR formulations were similarly affected by partial adherence, though once-daily dosing with lacosamide XR may offer clinical advantages, and formulations can be easily switched. These results support the use of lacosamide XR capsules as a once-daily alternative to lacosamide IR tablets.

Retrospective analysis of the biopharmaceutics characteristics of solid oral Modified-Release drug products in approved US FDA NDAs designated as Extended-Release or Delayed-Release formulations

BACKGROUND

Modified Release (MR) orally administered drugs products [Extended-Release (ER) and Delayed-Release (DR)] differ from Immediate-Release (IR) drug products in their drug release site and/or rate to offer therapeutic advantages. It is important to understand the biopharmaceutics factors that determine how a drug works in the gastrointestinal tract and the various pharmacokinetic properties that determine a drug's rate of absorption and release in the human body. To better understand the biopharmaceutics characteristics of ER and DR drug products, this study retrospectively analyzed submissions approved by the US Food and Drug Administration (FDA), from 2001 to 2021, and their corresponding review documents. This review work is expected to enhance the readers' understanding regarding the biopharmaceutics properties that supported approval of these products' ER claims, as per 21 CFR 320.25(f), and DR claims.

METHODS

A comprehensive search was conducted using the FDA's internal New Drug Application (NDA) database for ER and DR oral drug products approved between 2001 and 2021. The search yielded 87 ER applications (23 ER capsules and 64 ER tablets) and 21 DR applications (10 DR capsules, 11 DR tablets) for which electronic records were accessible. These products were analyzed for overall drug product design, dosing frequency compared to the reference (if applicable), degree of fluctuation, dissolution method, and alcohol dose-dumping.

RESULTS

Out of 87 total applications for ER drug products that were assessed, 62% of the ER tablets contained a polymer matrix formulation, and hypromellose (HPMC) was used in 50% of these products. 52% of the ER capsules consisted of polymer beads while about half of the DR drug products contained a non-bead formulation with a combination of polymers. The majority of ER drug products were found to have a reduction in dosing frequency and a decrease in the degree of fluctuation when compared to the IR reference product. The 13 ER drug products that exhibited an increase in degree of fluctuation exhibited general and pharmacodynamic benefits, such as reduced dosing frequency and reduced pill burden. The majority of DR formulations were developed to prevent drug degradation in the stomach, followed by to decrease potential stomach irritation, and lastly for localized release in the colon. The majority of ER drug products had 1:1 ratios of dissolution duration compared to dosing frequency (i.e., the majority of ER drug products had a dissolution duration of 24 h and were dosed every 24 h while those with a dissolution duration of 12 h were dosed every 12 h). The majority of ER applications had single-stage dissolution methods while most DR drug products used biphasic dissolution methods. All of the DR dissolution methods incorporated an acid stage of 2 h and a buffer stage with various timeframes. 53% the DR drug products had a ratio of dissolution duration to dosing frequency of 1:4 (e.g. a dissolution duration of 2 h to a dosing frequency of 8 h) or 1:8 (e.g. a dissolution duration of 2 h to a dosing frequency of 16 h). Of the ER tablets and DR drug products, 72% exhibited no alcohol dose-dumping under in vitro testing conditions. ER capsules, however, did not yield similar results-most of which exhibited alcohol induced dose-dumping. Alcohol dose dumping was mitigated by either in vivo studies or warnings on the drug product label.

CONCLUSION

The results of this study help the reader understand the design, characteristics, and pharmacological advantages of the ER and DR drug products for patient benefit; as well as the regulations governing the FDA's assessment of ER claims.

Dispersant-First Dispersive Liquid-Liquid Microextraction (DF-DLLME), a Novel Sample Preparation Procedure for NDMA Determination in Metformin Products

Since December 2019, global batch recalls of metformin pharmaceutical products have highlighted an urgent need to control N-nitrosodimethylamine (NDMA) contamination to demonstrate patient safety and maintain supply of this essential medicine. Due to their formulation, the metformin extended-release products present difficult analytical challenges for conventional sample preparation procedures, such as artefactual (in-situ) NDMA formation, gelling, and precipitation. To overcome these challenges, a new version of dispersive liquid-liquid microextraction (DLLME) termed dispersant-first DLLME (DF-DLLME) was developed and optimized for the analysis of NDMA in metformin extended-release products using a detailed Design of Experiments (DoE) to optimize sample preparation. Gas chromatography-high resolution accurate mass-mass spectrometry (GC-HRAM-MS) combined with automated DF-DLLME were successfully applied to monitor the NDMA levels of two different metformin extended-release AstraZeneca products to ultra-trace levels (parts per billion). The additional benefits associated with DF-DLLME, which include automation, time/costs saving, and greener sample preparation, make this novel technique easier to transfer from a development to Quality Control (QC) environment. In addition, this also offers an attractive candidate for the wider platform analysis of N-nitrosamines in pharmaceutical drug products.

3D screen printing technology enables fabrication of oral drug dosage forms with freely tailorable release profiles

3D printing offers new opportunities to customize oral dosage forms of pharmaceuticals for different patient populations, improving patient safety, care, and compliance. Although several notable 3D print technologies have been developed, such as inkjet printing, powder-based printing, selective laser sintering (SLS) printing, and fused deposition modelling (FDM), among others, their capacity is often limited by the number of printing heads. 3D screen-printing (3DSP) is based on a classic flatbed screen printing that is widely used in industrial applications for technical applications. 3DSP can build up thousands of units per screen simultaneously, enabling mass customization of pharmaceuticals. Here, we use 3DSP to investigate two novel paste formulations: immediate-release (IR) and extended-release (ER) using Paracetamol (acetaminophen) as the active pharmaceutical ingredient (API). Both disk-shaped and donut-shaped tablets were fabricated using one or both pastes to design drug delivery systems (DDS) with tailored API release profiles. The size and mass of the produced tablets demonstrated high uniformity. Characterization of the tablets physical properties, such as breaking force (25-39 N) and friability (0.002-0.237%), adhering to Ph. Eur (10th edition). Finally, drug release tests with a phosphate buffer at pH 5.8 showed Paracetamol release depended on the IR- and ER paste materials and their respective compartment size of the composite DDS, which can be readily varied using 3DSP. This work further demonstrates the potential of 3DSP to manufacture complex oral dosage forms exhibiting custom release functionalities for mass production.

Long-acting Parenteral Drug Delivery Systems for the Treatment of Chronic Diseases

The management of chronic conditions often requires patients to take daily medication for an extended duration. However, the need for daily dosing can lead to nonadherence to the therapy, which can result in the recurrence of the disease. Long-acting parenteral drug delivery systems have the potential to improve the treatment of chronic conditions. These systems use various technologies, such as oil-based injectables, PLGA-based microspheres, and in situ forming gel-based depots, to deliver different types of drugs. The use of long-acting parenteral formulations for the treatment of chronic infections such as HIV/AIDS and tuberculosis is a recent development in the field. Researchers are also exploring the use of long-acting parenteral formulations for the treatment of malaria, with the aim of reducing dosing frequency and improving adherence to treatment. This review discusses various aspects of long-acting formulation development, including the impact of the physicochemical properties of the drug, the type of long-acting formulation, and the route of administration. The clinical significance of long-acting formulations and recent advances in the field, such as long-acting nanoformulations and long-acting products currently in clinical trials, have also been highlighted.

A Randomized, Double-Blind, Crossover Study to Investigate the Pharmacokinetics of Extended-Release Melatonin Compared to Immediate-Release Melatonin in Healthy Adults

Exogenous melatonin can be helpful for treatment of some sleep disorders. However, immediate-release formulations are rapidly absorbed and cleared from the body making it difficult to provide coverage for an entire sleep period. Extended-release melatonin formulations can better mimic the naturally occurring melatonin profile and increase efficacy, but few studies have reported on their pharmacokinetics. To assess the pharmacokinetics of extended-release melatonin, we conducted a randomized, double-blind, crossover study of extended-release melatonin (4 mg) compared to immediate-release melatonin (4 mg) in 18 healthy adults, ages 18-65 years. Participants received immediate-release or extended-release melatonin in clinic after an 8 h fast, and blood samples were taken over a 10-h period. After a 7-day washout period, the same procedures were repeated with the melatonin form not previously received. Extended-release melatonin had a longer time to peak concentration (1.56 vs 0.6 h) and elimination half-life (1.63 vs 0.95 h) compared with immediate-release melatonin. Maximum concentration was lower for extended-release melatonin compared with immediate-release melatonin (7581 pg/mL vs 13120 pg/mL). Extended-release melatonin raised melatonin levels in as little as 15 min and sustained elevated melatonin levels (>300 pg/mL) for 6 h before falling below 50 pg/mL by 9 h. No clinically relevant adverse events were observed, and safety parameters remained within normal ranges for both formulations. The pharmacokinetic profile of this extended-release melatonin formulation suggests that it could be used for future efficacy studies of melatonin and sleep outcomes. This trial is registered at ClinicalTrials.gov, NCT04067791.

REsCue trial: Randomized controlled clinical trial with extended-release calcifediol in symptomatic COVID-19 outpatients

OBJECTIVES

This double-blind randomized controlled trial investigated raising serum 25-hydroxyvitamin D (25D) with extended-release calcifediol (ERC) on time to symptom resolution in patients with mild to moderate COVID-19.

METHODS

COVID-19 outpatients received oral ERC (300 mcg on days 1-3 and 60 mcg on days 4-27) or placebo (NCT04551911). Symptoms were self-reported daily. Primary end points were raising 25D to ≥50 ng/mL and decreasing resolution time for five aggregated symptoms (three respiratory).

RESULTS

In all, 171 patients were randomized, 160 treated and 134 (65 ERC, 69 placebo) retained. The average age was 43 y (range 18-71), 59% were women. The mean baseline 25D was 37 ± 1 (SE) ng/mL. In the full analysis set (FAS), 81% of patients in the ERC group achieved 25D levels of ≥50 ng/mL versus 15% in the placebo group (P < 0.0001). In the per-protocol (PP) population, mean 25D increased with ERC to 82 ± 4 (SE) ng/mL (P < 0.0001) by day 7; the placebo group trended lower. Symptom resolution time was unchanged in the FAS by ERC (hazard ratio [HR], 0.983; 95% confidence interval [CI], 0.695-1.390; P = 0.922). In the PP population, respiratory symptoms resolved 4 d faster when 25D was elevated above baseline level at both days 7 and 14 (median 6.5 versus 10.5 d; HR, 1.372; 95% CI, 0.945-1.991; P = 0.0962; Wilcoxon P = 0.0386). Symptoms resolved in both treatment groups to a similar extent by study end. Safety concerns including hypercalcemia were absent with ERC treatment.

CONCLUSION

ERC safely raised serum 25D to ≥50 ng/mL in outpatients with COVID-19, possibly accelerating resolution of respiratory symptoms and mitigating the risk for pneumonia. These findings warrant further study.

Retention in care for persons with opioid use disorder transitioning from sublingual to injectable buprenorphine

INTRODUCTION

In the current overdose epidemic, effective treatments for opioid use disorders (OUD), including innovations in medication delivery such as extended-release formulations, have the potential to improve treatment access and reduce treatment discontinuation. This study assessed treatment retention in a primary care-based, extended-release buprenorphine program.

METHODS

The study recruited individuals (n = 92) who transitioned from sublingual buprenorphine to extended-release buprenorphine (BUP-XR) in 2018-2019. The study defined the primary outcome, treatment retention, as three or more consecutive, monthly BUP-XR injections following the transition to BUP-XR in this retrospective chart review.

RESULTS

Participants' mean age was 38 years old and 67% were male. The average duration of sublingual buprenorphine prior to transition was 17.1 (±28.1) months. Three months after transition, 48% of extended-release buprenorphine patients had discontinued BUP-XR treatment. Persons with chronic pain were more likely, and those who had used heroin in the past month less likely to continue BUP-XR. Mean months on sublingual buprenorphine prior to BUP-XR initiation was 24.3 (±32.5) months for people who received 3+ post-induction injections compared to only 8.9 (±19.5) months for those who did not (p = .009).

CONCLUSIONS

Extended-release buprenorphine discontinuation was high in a real-world setting. Retention continues to represent a major obstacle to treatment effectiveness, and programs need interventions with even newer MOUD formulations.

Mucoadhesive buccal tablets with propranolol hydrochloride: Formulation development and in vivo performances in experimental essential hypertension

The objective of this study was to formulate extended-release mucoadhesive buccal tablets of propranolol hydrochloride in order to provide a prolonged absorption of propranolol hydrochloride from the buccal mucosa and to reduce presystemic metabolism and thus provide a better therapeutic effect. Besides, the aim was to perform comparative in vivo pharmacokinetic and hemodynamic studies of the developed extended-release (ER) propranolol hydrochloride 10 mg mucoadhesive buccal tablets and commercial immediate-release (IR) propranolol hydrochloride 10 mg tablets in spontaneously hypertensive rats. Formulation with 15% polyethylene oxide showed the highest degree of propranolol hydrochloride permeation, satisfactory mucoadhesiveness, and extended-release of propranolol hydrochloride, thus it was selected for further in vivo study. The pharmacokinetic study in rats showed the superiority of ER mucoadhesive buccal tablets over IR tablets in terms of propranolol hydrochloride absorption extent (AUC values: 70.32 ± 19.56 versus 31.69 ± 6.97 µg·h/mL), although lower maximum plasma propranolol hydrochloride concentration (C_max) was achieved. However, no statistically significant difference was observed in C_max between these treatments. The hemodynamic study showed that ER mucoadhesive buccal tablets provide a more pronounced decrease primarily in heart rate, but also in systolic and diastolic arterial pressure, as well as a longer heart rate reduction compared to IR tablets.

Comparing the pharmacokinetics of extended-release tacrolimus (LCP-TAC) to immediate-release formulations in kidney transplant patients

INTRODUCTION

One of the most commonly used immunosuppressants in organ transplant, tacrolimus exhibits wide interpatient and intrapatient variability and narrow therapeutic index that necessitates routine concentration monitoring and dosage adjustments. Availability of modified -release tacrolimus products offer once-daily dosing options. The objective of this review is to highlight and compare available pharmacokinetic (PK) data of extended-release tacrolimus tablets (LCP-TAC) to immediate-release tacrolimus (IR-TAC) in kidney transplant recipients.

AREAS COVERED

A review of the literature was performed using PubMed and Embase search to identify relevant articles evaluating PK data for LCP-TAC compared to IR-TAC in kidney transplant patients including special populations.

EXPERT OPINION

LCP-TAC's unique PK profile may be more favorable than IR-TAC. While the clinical impact of these PK differences have not been established, several outcomes are being evaluated in ongoing studies. Results of these studies will add information incrementally to care for kidney transplant patients. Larger prospective studies evaluating kidney and patient survival differences are needed but it is unlikely that they will be conducted. Given that the patent exclusivity of LCP-TAC for the next several years and imminent loss of exclusivity of PR-TAC, our opinion is the use of LCP-TAC will be increasing, especially in Europe.

Metformin extended-release versus metformin immediate-release for adults with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials

AIM

To compare the efficacy and tolerability of metformin extended-release (MXR) and the conventional metformin immediate-release (MIR) formulations in adults with type 2 diabetes mellitus (T2DM) METHODS: PubMed, the Cochrane Library, ClinicalTrials.gov and other sources were searched until 19 March 2021 for randomized controlled trials (RCTs) that compared equal daily doses of MXR and MIR in adults with T2DM. Random-effects model meta-analysis was performed to obtain pooled mean difference (MD) of change from baseline for continuous outcomes and risk ratio (RR) for dichotomous outcomes. Primary outcomes considered were HbA1c and key gastrointestinal (GI) symptoms (abdominal discomfort or pain, diarrhea, dyspepsia, and nausea & vomiting).

RESULTS

Nine RCTs that randomized a total of 2609 adults revealed that MIR was statistically associated with better HbA1c lowering (MD 0.09% [95% confidence interval or CI, 0.01%, 0.17%]), MXR only reduced dyspepsia (RR 0.58 [95% CI, 0.34, 0.98]), and both formulations were associated with similar cumulative incidence of other key GI symptoms.

CONCLUSIONS

MXR was associated with statistically worse but likely clinically similar HbA1c lowering and minimal improvement of GI intolerance compared to MIR. Protocol Registration: PROSPERO (CRD42019148008).

Determinants of interest in extended-released buprenorphine: A survey among 366 French patients treated with buprenorphine or methadone

AIM

To explore the factors determining the interest in extended-release buprenorphine (XR-BUP) injections among patients receiving opioid agonist treatment (OAT) in France.

METHODS

366 patients receiving OAT for opioid use disorder, recruited in 66 French centers, were interviewed from 12/2018 to 05/2019. A structured questionnaire assessed their interest in XR-BUP using a [1-10] Likert scale. 'More' vs. 'less' interested groups were defined using the median score of interest, and their characteristics were explored using adjusted odds ratios (aORs) and 95 % confidence interval (95 %CI). Independent variables were as follows: sociodemographic characteristics, OAT-related features (e.g., type of OAT and prescriber, dosing, or duration of treatment), OAT representations, and personal objectives of treatment.

RESULTS

The median interest in XR-BUP was 7 (interquartile range: 3-9) out of 10. The participants who were 'more interested' (i.e. those scoring ≥7) showed no substantial difference in sociodemographic characteristics, relative to the 'less interested' participants. However, they more frequently reported forgetting to take their OAT (OR = 1.81; CI95 % = 1.06-3.10) or reported experiencing situations where taking their OAT was impractical (aOR = 1.69; CI95 % = 1.05-2.73). Their treatment objective was more focused on stopping illicit drugs (aOR = 1.67; 95 %CI = 1.02-2.70), reducing health risks (aOR = 3.57; 95 %CI = 1.67-7.69) and craving (aOR = 2.38; 95 %CI = 1.39-4.02) or improving family (aOR = 1.81; 95 %CI = 1.03-3.13) or professional (aOR = 2.22; 95 %CI = 1.43-3.85) recovery.

CONCLUSIONS

In France, where the access to OAT is relatively unrestricted, the majority of participants were interested in XR-BUP formulations. Being interested was associated with treatment objectives focused on abstinence and recovery, and with experiencing constraints in taking a daily oral OAT.

Medication treatment for opioid use disorder in expectant mothers (MOMs): Design considerations for a pragmatic randomized trial comparing extended-release and daily buprenorphine formulations

Opioid use disorder (OUD) in pregnant women has increased significantly in recent years. Maintaining these women on sublingual (SL) buprenorphine (BUP) is an evidence-based practice but BUP-SL is associated with several disadvantages that an extended-release (XR) BUP formulation could eliminate. The National Drug Abuse Treatment Clinical Trials Network (CTN) is conducting an intent-to-treat, two-arm, open-label, pragmatic randomized controlled trial, Medication treatment for Opioid-dependent expectant Mothers (MOMs), to compare mother and infant outcomes of pregnant women with OUD treated with BUP-XR, relative to BUP-SL. A second aim is to determine the relative economic value of utilizing BUP-XR. Approximately 300 pregnant women with an estimated gestational age (EGA) of 6-30 weeks, recruited from 12 sites, will be randomized in a 1:1 ratio to BUP-XR or BUP-SL, balancing on site, EGA, and BUP-SL status (taking/not taking) at the time of randomization. Participants will be provided with study medication and attend weekly medication visits through 12 months postpartum. Participants will be invited to participate in two sub-studies to evaluate the: 1) mechanisms by which BUP-XR may improve mother and infant outcomes; and 2) effects of prenatal exposure to BUP-XR versus BUP-SL on infant neurodevelopment. This paper describes the key design decisions for the main trial made during protocol development. This Investigational New Drug (IND) trial uniquely uses pragmatic features where feasible in order to maximize external validity, hence increasing the potential to inform clinical practice guidelines and address multiple knowledge gaps for treatment of this patient population.

The influence of genetic polymorphisms in drug metabolism enzymes and transporters on the pharmacokinetics of different fluvastatin formulations

The purpose of the present study was to investigate the impact of genetic polymorphism on fluvastatin pharmacokinetics. In addition, we compared the fluvastatin pharmacokinetics differences between extended-release (ER) 80 mg tablet and immediate-release (IR) 40 mg capsule in terms of drug metabolism enzyme and transporter genetic polymorphisms. In this open-label, randomized, two-period, two-treatment, crossover study (n = 24), effects of ABCG2, SLCO1B1, ABCB1, CYP2C9 and CYP3A5 polymorphisms on the pharmacokinetics of fluvastatin were analyzed. The administration dosage for IR 40 mg and ER 80 mg were twice and once daily, respectively, for total 7 d. Blood samples for pharmacokinetic evaluation were taken on the 1st and 7th d. The lower exposure following ER was observed. For ER tablets, SLCO1B1 T521C genotype correlated with AUC_0-24 of repeat doses (P = 0.010). SLCO1B1 T521C genotype had no statistically significant effect on AUC_0-24 of IR capsule of fluvastatin after single or repeated doses. In vitro study demonstrated that when the concentration of fluvastatin was low (< 1 µmol/l), the uptake of fluvastatin in the HEK293-OATP1B1 with SLCO1B1 521TT (K_m =0.18 µmol/l) was faster than that with SLCO1B1 521CC (K_m =0.49 µmol/l), On the other hand, when concentration reached to higher level (> 1 µmol/l), transport velocity of fluvastatin by HEK293-OATP1B1 with SLCO1B1 521TT (K_m  = 11.4 µmol/l) and with SLCO1B1 521TCC (K_m =15.1 µmol/l) tend to be the same. It suggests that the increased effect of SLCO1B1 T521C genotype on ER formulation of fluvastatin was mainly caused by lower blood concentrations. We recommend that formulation should be incorporated into future pharmacogenomics studies.

Advances of Nano-Structured Extended-Release Local Anesthetics

Extended-release local anesthetics (LAs) have drawn increasing attention with their promising role in improving analgesia and reducing adverse events of LAs. Nano-structured carriers such as liposomes and polymersomes optimally meet the demands of/for extended-release, and have been utilized in drug delivery over decades and showed satisfactory results with extended-release. Based on mature technology of liposomes, EXPAREL, the first approved liposomal LA loaded with bupivacaine, has seen its success in an extended-release form. At the same time, polymersomes has advances over liposomes with complementary profiles, which inspires the emergence of hybrid carriers. This article summarized the recent research successes on nano-structured extended-release LAs, of which liposomal and polymeric are mainstream systems. Furthermore, with continual optimization, drug delivery systems carry properties beyond simple transportation, such as specificity and responsiveness. In the near future, we may achieve targeted delivery and controlled-release properties to satisfy various analgesic requirements.

ProHeart® 12, a moxidectin extended-release injectable formulation for prevention of heartworm (Dirofilaria immitis) disease in dogs in the USA for 12 months

BACKGROUND

The efficacy of an extended-release injectable moxidectin (0.5 mg/kg) suspension (ProHeart® 12) (PH 12) in preventing the development of Dirofilaria immitis in dogs for 12 months was investigated in laboratory and field studies in the USA.

METHODS

In each of two laboratory studies, 20 dogs ≥ 12 months of age were randomly allocated to receive a subcutaneous injection of saline or PH 12 on Day 0 and were then inoculated with 50 D. immitis third-stage larvae (L3) on Day 365. All dogs were necropsied ~ 5 months post-inoculation for adult worm counts. The field efficacy study included dogs ≥ 10 months of age from 19 veterinary clinics in the USA treated with either 20 monthly doses of Heartgard® Plus (HG Plus) (296 dogs) or two doses of PH 12 (297 dogs) on Days 0 and 365. Efficacy was determined on Days 365, 480 and 605 using adult HW antigen and microfilaria testing to assess adult HW infection.

RESULTS

PH 12 was 100% effective in preventing HW disease in all three of these studies. In the laboratory studies, no PH 12-treated dogs had any adult HWs, whereas all control dogs in both studies had adult HWs [geometric mean, 30.2 (range, 22-37) for Study 1 and 32.6 (22-44) for Study 2]. In the field study, all dogs treated with PH 12 tested negative for adult HW infection on all test days (Days, 365, 480 and 605), whereas four dogs receiving HG Plus (positive control) tested positive for HWs during the study (three dogs on Day 365 and one dog on Day 480). All four dogs treated with HG Plus that subsequently tested positive for HWs during the field study were from the lower Mississippi River Valley region, where HW resistance to macrocyclic lactone preventives has been confirmed to occur. PH 12 was significantly better than HG Plus in preventing heartworm disease in the field study (P = 0.0367). PH 12 was well-tolerated in both laboratory and field studies.

CONCLUSIONS

A single dose of ProHeart® 12 was 100% effective in preventing heartworm disease in dogs for a full year in both laboratory and field studies.

Opioid users' willingness to receive prolonged-release buprenorphine depot injections for opioid use disorder

AIMS

Prolonged-release implantable and depot injection formulations of buprenorphine are very recent developments in the treatment of opioid use disorder. Such formulations remove the need for daily dosing and provide patients with sustained concentrations of buprenorphine over a period of weeks or months. We explored opioid users' personal willingness to receive prolonged-release buprenorphine depot injections and factors influencing their interest.

METHODS

The study took place in London during 2018, before depot buprenorphine was licensed for use in Europe. Thirty-six face-to-face, semi-structured qualitative interviews were conducted with people who were: i) using heroin daily and not receiving any treatment for opioid use (n = 12); or ii) prescribed daily oral buprenorphine (n = 12); or iii) prescribed daily oral methadone (n = 12). Participants were asked about their willingness to receive depot buprenorphine and were encouraged to discuss factors that might alter their opinions. Interview data were analysed following the stages of Iterative Categorization.

FINDINGS

Participants expressed a high level of willingness to receive depot buprenorphine. Their views were influenced both positively and negatively by six key features of depot buprenorphine: i) reduced contact with pharmacies and drug treatment services; ii) impact on illicit drug use and recovery; iii) the perceived effectiveness of depot buprenorphine; iv) the duration and dosage of depot buprenorphine injections; v) clinical administration of the depot buprenorphine injection; and vi) potential for side effects associated with the depot buprenorphine injection.

CONCLUSIONS

Willingness to receive a given medication is complex, individual and changeable. Opioid users seem likely to welcome greater choice and flexibility in respect of opioid agonist medications and appear more likely to accept and adhere to depot buprenorphine if it enables them to reduce their illicit drug use and facilitates their recovery. Research is now needed to assess whether patients' reported willingness to receive depot buprenorphine translates into actual uptake and adherence.

Extended-release injectable naltrexone for opioid use disorder: a systematic review

AIMS

To review systematically the published literature on extended-release naltrexone (XR-NTX, Vivitrol^® ), marketed as a once-per-month injection product to treat opioid use disorder. We addressed the following questions: (1) how successful is induction on XR-NTX; (2) what are adherence rates to XR-NTX; and (3) does XR-NTX decrease opioid use? Factors associated with these outcomes as well as overdose rates were examined.

METHODS

We searched PubMed and used Google Scholar for forward citation searches of peer-reviewed papers from January 2006 to June 2017. Studies that included individuals seeking treatment for opioid use disorder who were offered XR-NTX were included.

RESULTS

We identified and included 34 studies. Pooled estimates showed that XR-NTX induction success was lower in studies that included individuals that required opioid detoxification [62.6%, 95% confidence interval (CI) = 54.5-70.0%] compared with studies that included individuals already detoxified from opioids (85.0%, 95% CI = 78.0-90.1%); 44.2% (95% CI = 33.1-55.9%) of individuals took all scheduled injections of XR-NTX, which were usually six or fewer. Adherence was higher in prospective investigational studies (i.e. studies conducted in a research context according to a study protocol) compared to retrospective studies of medical records taken from routine care (6-month rates: 46.7%, 95% CI = 34.5-59.2% versus 10.5%, 95% CI = 4.6-22.4%, respectively). Compared with referral to treatment, XR-NTX reduced opioid use in adults under criminal justice supervision and when administered to inmates before release. XR-NTX reduced opioid use compared with placebo in Russian adults, but this effect was confounded by differential retention between study groups. XR-NTX showed similar efficacy to buprenorphine when randomization occurred after detoxification, but was inferior to buprenorphine when randomization occurred prior to detoxification.

CONCLUSIONS

Many individuals intending to start extended-release naltrexone (XR-NTX) do not and most who do start XR-NTX discontinue treatment prematurely, two factors that limit its clinical utility significantly. XR-NTX appears to decrease opioid use but there are few experimental demonstrations of this effect.

A multicenter, observational study of lanreotide depot/autogel (LAN) in patients with acromegaly in the United States: 2-year experience from the SODA registry

PURPOSE

This analysis evaluates the 2-year effectiveness and safety of lanreotide depot/autogel (LAN), as well as treatment convenience and acromegaly symptom relief, from the Somatuline^® Depot for Acromegaly (SODA) registry, a post-marketing, open-label, observational, multicenter, United States registry study.

METHODS

Patients with acromegaly treated with LAN were eligible for enrollment. Demographics, LAN dose, extended dosing interval (EDI) (interval of injections ≥42 days), insulin-like growth factor 1 (IGF-1), growth hormone (GH), glycated hemoglobin, adverse events (AEs), injection convenience, and symptom data were collected.

RESULTS

As of September 29, 2014, 241 patients were enrolled in SODA. IGF-1 levels below age- and gender-adjusted upper normal limit (ULN) were achieved in 71.2% at month (M) 12 and 74.4% at M24; GH ≤2.5 µg/L in 83.3% at M12 and 80.0% at M24; GH <1.0 µg/L in 61.7% at M12 and 61.4% at M24. Both IGF-1 < ULN and GH ≤2.5 µg/L were achieved in 65.0% at M12 and 54.8% at M24; both IGF-1 < ULN and GH < 1.0 µg/L were achieved in 51.7 and 42.9% at M12 and M24, respectively. EDI regimen was 5.0% at baseline and 12.0% at M24. At M24, acromegaly symptoms appeared stable or improved. The most common AE was arthralgia (25.7%). Among 106 serious AEs reported by 42 patients, 10 were deemed related to therapy in 9 patients. At M24, 73.1% of patients rated LAN as convenient.

CONCLUSIONS

SODA indicates 2-year biochemical control with majority of patients achieving both IGF-1 < ULN and GH ≤2.5 µg/L. LAN was generally well tolerated with no new or unexpected safety signals reported during the observation period. clinicaltrials.gov Clinical Trial Identifier: NCT00686348.

An abuse-deterrent, microsphere-in-capsule formulation of extended-release oxycodone: alternative modes of administration to facilitate pain management in patients with dysphagia

BACKGROUND

Patients with chronic pain may experience difficulty swallowing, in part due to worsening disease, comorbid conditions, iatrogenic etiology, or age. Patients or caregivers may manipulate extended-release (ER) opioid formulations to facilitate oral dosing due to a lack of therapeutic options that allow for sprinkle or enteral feeding tube administration. If crushed or broken, current oral ER opioids can be associated with adverse sequelae, including risk of potentially fatal overdose.

OBJECTIVE

To review the safety, in vitro dissolution data, and in vivo pharmacokinetic data that support alternative modes of administration of oxycodone DETERx (Xtampza ER) via sprinkling onto soft foods for oral ingestion or via enteral feeding tubes.

METHODS

A review of oxycodone DETERx data from in vitro and in vivo studies was conducted to demonstrate support for alternative routes and modes of administration.

RESULTS

There was no difference in the dissolution profile when administered with various soft foods or when mixed with various liquid vehicles and administered via nasogastric (NG) or gastrostomy (G) tubes, based on in vitro studies. When sprinkled onto applesauce and administered orally, the microspheres were bioequivalent to the intact oxycodone capsules. When crushed or chewed, the formulation maintained its pharmacokinetic profile; no bolus dose of opioid was released. The sprinkle-dose study was limited by the single-dose study design, as well as the small sample size.

CONCLUSIONS

Oxycodone DETERx is the first ER oxycodone formulation that can be administered either intact, sprinkled onto soft foods, or via NG/G tubes, thereby providing options for treating pain in patients who have difficulty swallowing.

Strengths, weaknesses, opportunities and challenges for long acting injectable therapies: Insights for applications in HIV therapy

Advances in solid drug nanoparticle technologies have resulted in a number of long-acting (LA) formulations with the potential for once monthly or longer administration. Such formulations offer great utility for chronic diseases, particularly when a lack of medication compliance may be detrimental to treatment response. Two such formulations are in clinical development for HIV but the concept of LA delivery has its origins in indications such as schizophrenia and contraception. Many terms have been utilised to describe the LA approach and standardisation would be beneficial. Ultimately, definitions will depend upon specific indications and routes of delivery, but for HIV we propose benchmarks that reflect perceived clinical benefits and available data on patient attitudes. Specifically, we propose dosing intervals of ≥1week, ≥1month or ≥6months, for oral, injectable or implantable strategies, respectively. This review focuses upon the critical importance of potency in achieving the LA outcome for injectable formulations and explores established and emerging technologies that have been employed across indications. Key technological challenges such as the need for consistency and ease of administration for drug combinations, are also discussed. Finally, the review explores the gaps in knowledge regarding the pharmacology of drug release from particulate-based LA injectable suspensions. A number of hypotheses are discussed based upon available data relating to local drug metabolism, active transport systems, the lymphatics, macrophages and patient-specific factors. Greater knowledge of the mechanisms that underpin drug release and protracted exposure will help facilitate further development of this strategy to achieve the promising clinical benefits.

In vitro/in vivo evaluation of HPMC/alginate based extended-release matrix tablets of cefpodoxime proxetil

The purpose of this research was to assessment of antimicrobial activity and in vitro/in vivo evaluation of cefpodoxime proxetil extended-release (ER) tablet for once daily administration. The tablets were prepared using combination of biodegradable polysaccharides including hydroxypropyl methylcellulose and sodium alginate as matrix material to achieve pH-independent ER release. The tablets were found within the permissible limits for various physicochemical parameters. The in vitro drug release showed that the drug was released over a period of 24h in a sustained release manner. The drug release followed Higuchi kinetics as these plots showed the highest linearity (R(2)=0.9833), but a close relationship was also observed with zero-order kinetics (R(2)=0.9088) and the drug release mechanism was found to be of anomalous or non-Fickian type. Further, in vitro drug release was assessed by antimicrobial assay and it revealed that drug release through 24h periods was above the MIC. In vivo investigation in rabbits showed ER pharmacokinetic profile of cefpodoxime from the matrix tablets. A good correlation of drug absorption in vivo and drug release in vitro (R(2)=0.9785) was observed. These results suggested that the investigated CFP matrix tablets have a potential for extended-release dosage forms.

Evaluation of the durability of pain relief throughout a 12 hour dosing interval of a novel, extended-release, abuse-deterrent formulation of oxycodone

BACKGROUND

Abuse deterrent formulations (ADF) are designed to prevent the misuse of opioids by tampering (e.g. physical and chemical manipulation) in order to ingest the opioid in a manner other than intended. Extended-release (ER) formulations are formulated with a larger drug load than immediate-release (IR) formulations, which makes ER opioids more desirable to drug abusers than I.R. formulations. ADFs, therefore, are particularly useful with ER opioid agents, which are designed to produce consistent analgesia over prolonged dosing intervals. However, the drug release properties of these formulations vary and sometimes may not provide adequate pain relief throughout the intended dosing interval, requiring patients to take additional medication for pain relief. Oxycodone DETERx* (Xtampza ER * ) is a novel, microsphere-in-capsule opioid formulation, which allows for twice daily dosing (i.e. every 12 hours) and mitigates the ability to tamper with the formulation.

OBJECTIVE

To evaluate the durability of pain relief of a novel formulation of oxycodone throughout the 12 hour dosing interval.

RESEARCH DESIGN AND METHODS

This study is a post-hoc analysis of 193 subjects in a Phase 3 randomized withdrawal, double-blind, placebo-controlled, enriched-enrollment, parallel-group, multicenter, 12-week clinical study.

MAIN OUTCOME MEASURES

The analysis evaluated the frequency and distribution of use of oxycodone ER and rescue medication during the Double-blind Maintenance Phase of the study.

RESULTS

Usage patterns captured by an electronic diary indicated limited overall and limited per-day use of rescue medication with no increase in rescue medication consumption 8 to 12 hours post-dose, suggesting that subjects did not experience end-of-dose failure during this time period.

LIMITATIONS

This study is limited in that it is a post-hoc analysis based on data gathered electronically from a large, prospective, double-blind, randomized, placebo-controlled, Phase 3 clinical study.

CONCLUSION

The evaluation of dosing patterns indicates that this ER oxycodone capsule formulation has durability of effect over the entire 12-hour dosing interval. These data support the use of abuse-deterrent oxycodone ER as a 12-hour dosing formulation.

Design of a randomized controlled trial of extended-release naltrexone versus daily buprenorphine-naloxone for opioid dependence in Norway (NTX-SBX)

BACKGROUND

Current guidelines for opioid dependence recommend daily maintenance of physical dependence with methadone or buprenorphine, and discourage abstinence due to the high risk of relapse and overdose. Extended-release formulations of the opioid antagonist naltrexone (XR-NTX) block heroin and other opioid agonists competitively for around 4 weeks per administration. XR-NTX thus enables opioid users to experience abstinence from opioid agonists with greatly reduced risk of overdose compared to medication-free abstinence. While XR-NTX has shown promise compared to placebo and daily naltrexone tablets, there is limited information on long-term safety and its performance compared to daily maintenance treatment.

METHODS/DESIGN

In this five-hospital RCT with long-term follow-up, we aim to recruit n = 180 patients in treatment for opioid dependence and allocate them in an open, randomized manner (1:1) to receive either 4-week XR-NTX or daily buprenorphine-naloxone (BP-NLX) for the duration of 12 weeks. Allocation is open-label due to the risk of overdose during attempts to self-unmask allocation using heroin. Urine drug tests are scheduled every week with follow-up visits & assessment every 4 weeks. Primary outcomes are abstinence from illicit opioids in urine drug tests and self-report, as well as retention in treatment. Secondary outcomes include other substance use, injecting behavior, drug craving, mental health, quality of life, treatment satisfaction, abstinence motivation, opioid agonist effect rating, insomnia, and pain. Observation is continued for another 36 weeks in order to assess longer-term safety, adherence and effectiveness. The study is an investigator-initiated trial, funded by public grants and approved by an Independent Ethical Committee (the Regional Ethical Committee for Research South-East B # 2011/1320) and the Norwegian Medicines Agency.

DISCUSSION

Despite minor implementation problems, the protocol appears sufficiently robust to generate results of high interest to patients, clinicians and policy makers.

TRIAL REGISTRATION

Clinicaltrials.gov # NCT01717963 , first registered: Oct 28, 2012. Protocol version # 3C, June 12th 2012.

Lipophilic nalmefene prodrugs to achieve a one-month sustained release

Nalmefene is an opioid antagonist which as a once-a-day tablet formulation has recently been approved for reducing ethanol intake in alcoholic subjects. In order to address the compliance issue in this patient population, a number of potential nalmefene prodrugs were synthesized with the aim of providing a formulation that could provide plasma drug concentrations in the region of 0.5-1.0ng/mL for a one-month period when dosed intramuscular to dogs or minipigs. In an initial series of studies, three different lipophilic nalmefene derivatives were evaluated: the palmitate (C16), the octadecyl glutarate diester (C18-C5) and the decyl carbamate (CB10). They were administered intramuscularly to dogs in a sesame oil solution at a dose of 1mg-eq. nalmefene/kg. The decyl carbamate was released relatively quickly from the oil depot and its carbamate bond was too stable to be used as a prodrug. The other two derivatives delivered a fairly constant level of 0.2-0.3ng nalmefene/mL plasma for one month and since there was no significant difference between these two, the less complex palmitate monoester was chosen to demonstrate that dog plasma nalmefene concentrations were dose-dependent at 1, 5 and 20mg-eq. nalmefene/kg. In a second set of experiments, the effect of the chain length of the fatty acid monoester promoieties was examined. The increasingly lipophilic octanoate (C8), decanoate (C10) and dodecanoate (C12) derivatives were evaluated in dogs and in minipigs, at a dose of 5mg-eq. nalmefene/kg and plasma nalmefene concentrations were measured over a four-week period. The pharmacokinetic profiles were very similar in both species with Cmax decreasing and Tmax increasing with increasing fatty acid chain length and the target plasma concentrations (0.5-1.0ng/mL over a month-long period) were achieved with the dodecanoate (C12) prodrug. These data therefore demonstrate that sustained plasma nalmefene concentrations can be achieved in both dog and minipig using nalmefene prodrugs and that the pharmacokinetic profile of nalmefene can be tuned by varying the length of the alkyl group.

Use of computer simulations to test the concept of dose forgiveness in the era of extended-release (XR) drugs

"Forgiveness" - the difference between a drug's postdose duration of action and its prescribed dosing interval - estimates the margin of therapeutic effect following a missed dose. Because this margin presumably decreases as dosing becomes less frequent, QD dosing of an antiepileptic drug (AED) is expected to be less forgiving than more frequent (e.g., BID) dosing of that same AED. However, if the AED is reformulated as an extended-release (XR) preparation, drug input may be prolonged relative to its immediate-release (IR) counterpart. It therefore stands to reason that forgiveness could be increased by an XR AED that extends the period during which therapeutic plasma concentrations are maintained if a dose is missed. Computer simulation was used to estimate forgiveness for an IR formulation of a hypothetical AED and its XR counterparts reformulated for less frequent dosing. Simulations determined forgiveness when the hypothetical IR AED was dosed TID, BID, and QD and when suitably designed XR formulations were dosed BID and QD. Simulations showed that forgiveness for an XR formulation can equal or exceed that for an IR formulation dosed more frequently.

immediate-release formulations

BACKGROUND

Once-daily extended-release (XR) antiepileptic drugs (AEDs) offer potential adherence and tolerability advantages over their BID immediate-release (IR) counterparts. However, patients with epilepsy will inevitably be at least occasionally nonadherent with a prescribed dosing regimen, regardless of formulation. Although perturbations in plasma concentrations due to dosing irregularities may have clinical consequences for AEDs with concentration-response relationships, clinical studies that deliberately expose patients to specific dosing irregularities in order to assess the effect on plasma concentrations and determine appropriate corrective actions would be unethical.

METHODS

Computer simulation was used to assess the impact of irregular dosing on topiramate (TPM) concentrations in noninduced (monotherapy/neutral cotherapy) and induced (adjunctive therapy with enzyme-inducing AEDs) states using a population pharmacokinetic (PK) model developed to predict steady-state plasma concentration-time profiles produced by once-daily Trokendi XR (extended-release topiramate capsules, Supernus Pharmaceuticals) and BID TPM-IR.

RESULTS

Computer simulations predicted that, relative to adherent dosing, delaying a dose 4 to 24h in noninduced patients would decrease trough (Cmin) levels 9% to 31% in the case of TPM-IR and 6% to 27% with Trokendi XR; a single omitted dose would reduce Cmin by 21% (TPM-IR) and 27% (Trokendi XR). After dose recovery to correct for a delayed or omitted dose, simulated peak concentration (Cmax) was higher than steady-state Cmax, regardless of formulation, although the magnitude of "overshoot" was consistently lower with Trokendi XR vs. TPM-IR. Doubling of a dose would increase Cmax by 26% and 28%, respectively. Predicted changes for nonadherent vs. adherent dosing were greater in the induced vs. noninduced state but were generally comparable for the two TPM formulations. Because the long half-life of TPM has been cited as a justification for QD dosing of TPM-IR, simulations also compared steady-state PK profiles of once-daily Trokendi XR and QD TPM-IR. Predicted TPM plasma concentration-time profiles were markedly different, as demonstrated by peak-trough fluctuation (QD TPM-IR, 64%; QD Trokendi XR, 18%) and 34% lower Cmin with QD TPM-IR.

CONCLUSIONS

Based on these simulations, dosing irregularities with once-daily Trokendi XR should pose no greater risk than with BID TPM-IR. In the event of a delayed or omitted Trokendi XR dose, TPM concentrations can be restored in noninduced and induced states by administering the delayed/omitted dose at any time during the next dosing interval or by adding the missed dose to the next scheduled dose.

Efficacy of once-daily extended-release topiramate (USL255): a subgroup analysis based on the level of treatment resistance

Results from a previously conducted global phase III study (PREVAIL; NCT01142193) demonstrate the safety and efficacy of once-daily USL255, Qudexy™ XR (topiramate) extended-release capsules, as adjunctive treatment of drug-resistant partial-onset seizures (POSs). In this study, we report a post hoc analysis of PREVAIL data according to patient level of treatment resistance (based upon the number of concomitant antiepileptic drugs [AEDs] and lifetime AEDs) at baseline, with patients defined as either having "highly" drug-resistant seizures (≥ 2 concurrent AEDs and ≥ 4 lifetime AEDs) or having "less" drug-resistant seizures (1 concurrent AED or <4 lifetime AEDs) at baseline. For each subgroup, median percent reduction in POS frequency (primary endpoint), responder rate, Clinical Global Impression of Change (CGI-C), and Quality of Life in Epilepsy--Problems (QOLIE-31-P) survey were assessed. Of 249 PREVAIL patients, 115 were classified as having highly drug-resistant seizures (USL255: n = 52, placebo: n = 63), and 134 were classified as having less drug-resistant seizures (USL255: n = 72, placebo: n = 62) at baseline. For the primary endpoint, USL255 resulted in significantly better seizure outcomes compared with placebo regardless of drug-resistant status (P = .004 and P = .040 for "highly" and "less", respectively). Responder rate was also significantly improved in patients with highly drug-resistant group (P = .023). The CGI-C scores indicated significant improvement in both subgroups (P = .003 and P = .013 for "highly" and "less", respectively). On the QOLIE-31-P, a significant improvement on the seizure worry subscale for the group with less drug-resistant seizures was noted in USL255-treated patients compared with placebo-treated patients (P = .003); the overall score and all other subscales were not significantly different for both subgroups. We conclude that USL255 led to significant improvements across multiple outcomes compared with placebo, including in those classified as having highly drug-resistant seizures to prior treatment, making it a valuable treatment option for patients with epilepsy.

Complementary pharmacokinetic measures to further define the profile of once-daily OROS hydromorphone ER during single-dose and steady-state dosing

Conventional measures such as maximum plasma concentration (C_max) and area under the concentration versus time curve (AUC) may be insufficient to fully describe the pharmacokinetic (PK) profile of extended-release (ER) formulations. A complementary measure, the half-value duration (HVD), corresponds to the period of time during a dosing cycle that plasma concentration is at or above half the value of the maximal concentration (i.e. ≥50% C_max). The current post-hoc analysis uses data from 2 previously published studies comparing the PK profiles and HVD of OROS hydromorphone ER (16 mg administered once daily) and immediate-release (IR) hydromorphone (4 mg administered every 6 hours), calculating single-dose and steady-state condition values. Bioequivalence was demonstrated between the 2 formulations. Mean steady-state once-daily OROS hydromorphone ER concentrations were elevated for most of the 24-hour dosing period and for significantly longer than with the dose-equivalent IR hydromorphone regimen. The duration of time spent ≥50% C_max was, on average, 2.7 times longer at steady state for the ER formulation, which also maintained steady-state hydromorphone plasma concentrations, with 65% lower mean degree of fluctuation versus IR hydromorphone. Both formulations appeared to be well tolerated.

Extended-release medications for children and adolescents with attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) affects one in 20 Canadian children, and is associated with unfavourable academic and employment records, high rates of injury and substance abuse, poor interpersonal relationships, poor mental health outcomes and poor quality of life. Medications have been shown to be efficacious in treating ADHD symptoms in controlled trials, and are associated with better social and health outcomes in observational studies. Extended-release (XR) medications for ADHD are preferred over short-acting immediate-release medications by many families and their treating physicians. The XR preparations are often unaffordable for affected families who are disproportionally among the lower socioeconomic strata.The objective of the present statement was to critically appraise the evidence for the relative effectiveness of XR versus immediate-release medications, and to make recommendations for their appropriate use in the treatment of ADHD.When medication is indicated, XR preparations should be considered as first-line therapy for ADHD because they are more effective and less likely to be diverted. Future research and cost-benefit analyses should consider both efficacy and effectiveness, and the diversion and misuse potentials of these medications. Industry, insurance companies and government must work together to make these medications accessible to all children and youth with ADHD.