The potent BACE1 inhibitor LY2886721 elicits robust central Aß pharmacodynamic responses in mice, dogs, and humans.

BACE1 is a key protease controlling the formation of amyloid ß, a peptide hypothesized to play a significant role in the pathogenesis of Alzheimer's disease (AD). Therefore, the development of potent and selective inhibitors of BACE1 has been a focus of many drug discovery efforts in academia and industry. Herein, we report the nonclinical and early clinical development of LY2886721, a BACE1 active site inhibitor that reached phase 2 clinical trials in AD. LY2886721 has high selectivity against key off-target proteases, which efficiently translates in vitro activity into robust in vivo amyloid ß lowering in nonclinical animal models. Similar potent and persistent amyloid ß lowering was observed in plasma and lumbar CSF when single and multiple doses of LY2886721 were administered to healthy human subjects. Collectively, these data add support for BACE1 inhibition as an effective means of amyloid lowering and as an attractive target for potential disease modification therapy in AD.

High-quality triplicate electrocardiogram monitoring in a first-in-man study: potential for early detection of drug-induced QT prolongation.

BACKGROUND: QT interval prolongation is associated with an increased risk of potentially fatal ventricular tachycardias, including torsade de pointes. Regulatory guidance recommends the "thorough QT/QTc" (TQT) study as the gold standard for assessing the propensity of novel nonantiarrhythmic drugs to delay cardiac repolarization. An opportunity exists, however, to use high-quality electrocardiogram (ECG) data from first-in-man trials as an exploratory and complementary approach to gain early insight into potential risk of QT prolongation. METHODS: We collected high-quality, triplicate, 12-lead ECG data during a first-in-man trial of a drug developed for the treatment of Type 2 diabetes that had shown in vitro hERG inhibition and potential to prolong QT intervals in an animal model. RESULTS: QTc prolongation was observed at the highest dose, leading to a maximum QTcF prolongation > 19 ms at 6 hours after the 14th daily dose. QTcF increases from time-matched baseline relative to placebo were positively correlated with peak plasma concentrations. CONCLUSIONS: Clinically relevant QT interval prolongations can be detected during first-in-man studies using high-quality ECG monitoring. Such data may facilitate early decision making on whether to terminate the development of a compound and invest resources in more promising molecules; and it may enable more efficient TQT study design or preclude the need for future TQT studies.

Pharmacokinetics, pharmacodynamics, and safety of clevidipine after prolonged continuous infusion in subjects with mild to moderate essential hypertension.

PURPOSE: Clevidipine is a rapidly-acting intravenous dihydropyridine antihypertensive acting via calcium channel blockade. This was a randomized, single-blind, parallel-design study of a 72-h continuous clevidipine infusion. METHOD: Doses of 2, 4, 8, or 16.0 mg/h or placebo were evaluated in 61 subjects with mild to moderate essential hypertension. IV clevidipine or placebo was initiated at 2.0 mg/h and force-titrated in doubling increments every 3 min to target dose, then maintained for 72 h. Blood pressure and heart rate were measured during infusion, and for 4, 6 and 8 h after termination of infusion, although oral therapy could be restarted at 4 h. Clevidipine blood levels were obtained during infusion and for 1 hour after termination. RESULTS: Rapid onset of drug effect occurred at all clevidipine dose levels, with consistent pharmacokinetics and rapid offset after 72-h infusion. No evidence of tolerance to the clevidipine drug effect was observed at any dose level over the 72-h infusion. No evidence of rebound hypertension was found for either 4 or 6 h after termination of the clevidipine infusion. At 8 h following cessation of clevidipine, blood pressure was not significantly higher than at baseline. Placebo-treated subjects had blood pressures lower than baseline at 8 h following infusion termination; hence, placebo-adjusted blood pressures tended to be slightly higher than baseline. CONCLUSION: This study supports the use of up to 72 h of IV clevidipine therapy for the management of blood pressure, with consistent pharmacokinetic/pharmacodynamic characteristics and context insensitive half-life across the dose ranges evaluated.

Skin concentrations and pharmacokinetics of posaconazole after oral administration.

A randomized, single-center, open-label study of posaconazole (POS) was performed to determine the concentration of POS in the skin of 30 healthy adult human subjects receiving 400 mg POS oral suspension twice daily for 8 days with a high-fat meal. Blood samples for plasma POS level determination were collected at prespecified times on day 1 and day 8. From each subject, two 4-mm skin punch biopsy samples were obtained, one immediately before or after both the first and last doses of POS. A MIC(90) value of 250 ng/ml, which encompasses the majority of common dermatophytes, was used to calculate the time above the MIC(90) in plasma and skin. On days 1 and 8, POS attained peak plasma concentrations at median times of 8 and 5 h, respectively. On days 1 and 8, POS peak skin concentrations were attained at 12 and 3 h, respectively; peak skin concentrations were produced from a single composite profile. On day 8, POS concentrations in skin and plasma for the entire dosing interval were severalfold higher than the MIC(90). POS dosed at 400 mg twice daily per os was well tolerated in healthy subjects. Two subjects reported increased alanine aminotransferase (ALT) levels. The findings of this study demonstrate adequate skin penetration and have certain implications for the treatment of dermatophytic skin and nail infections.

Effect of varying amounts of a liquid nutritional supplement on the pharmacokinetics of posaconazole in healthy volunteers.

The aim of this single-center, phase 1, randomized, 5 by 5 crossover, open-label study was to determine the effects of varying amounts of a nutritional supplement (Boost Plus) on the pharmacokinetics of posaconazole in 30 healthy volunteers. After an overnight fast, subjects were administered a single dose of 400 mg posaconazole oral suspension alone or following Boost Plus (8 fluid ounces [oz] [240 ml], 4 oz [120 ml], 2 oz [60 ml], or 1 oz [30 ml]). Subjects were randomized to receive all five treatments in different sequences, with a 14-day washout between treatments. Primary pharmacokinetic variables--area under the concentration-time curve from time zero to the time of the final quantifiable sample (AUC(tf)), maximum observed plasma concentration (C(max)), time to C(max) (T(max)), and relative bioavailability--were assessed up to 5 days postdose. Safety assessments included testing for adverse events, clinical laboratory tests, measurement of vital signs, physical examinations, and electrocardiograms. Posaconazole bioavailability increased almost linearly with increasing amounts of Boost Plus. Based on log-transformed data, the relative bioavailabilities (AUCs) of posaconazole were 35% (fasting), 48% (1 oz), 60% (2 oz), and 77% (4 oz) of the level reached in the presence of 8 oz Boost Plus, whereas T(max) was unaffected. Compared with the levels reached under fasting conditions, posaconazole C(max) and AUC values increased 3.5- and 2.9-fold, respectively, when given with 8 oz Boost Plus. Single doses of posaconazole at 400 mg alone and with 1, 2, 4, or 8 oz Boost Plus were safe and well tolerated in healthy subjects.

Orally inhaled levodopa (CVT-301) for early morning OFF periods in Parkinson's disease.

BACKGROUND: CVT-301 (Inbrija) is a self-administered orally inhaled levodopa approved for the intermittent treatment of OFF episodes in patients with Parkinson's disease (PD) treated with carbidopa/levodopa. Prior studies only evaluated CVT-301 after the first ON of the day. OBJECTIVE AND METHODS: The objective of this study was to evaluate the safety and tolerability of CVT-301 for early morning OFF. Using a randomized, double-blind, 2-way crossover design, eligible patients in the morning OFF state (having not received PD medication overnight) received a single dose of CVT-301 84 mg or placebo on 2 dosing days, immediately after their first morning oral carbidopa/levodopa dose. Safety assessments included treatment-emergent adverse events, vital signs, and patient- and examiner-reported dyskinesia. An exploratory efficacy assessment was examiner-rated time-to-ON with carbidopa/levodopa + CVT-301 vs carbidopa/levodopa + placebo. RESULTS: Of the 36 patients (mean age 62.9 years) who enrolled and completed the study, 9 (25.0%) reported treatment-emergent adverse events following CVT-301 administration; 4 (11.1%) reported treatment-emergent adverse events following placebo. The most common adverse event was cough (4 [11.1%] for CVT-301 vs 1 [2.8%] for placebo), which was typically mild and transient. Incidence of asymptomatic orthostatic hypotension (CVT-301, 6; placebo, 7) and examiner-rated dyskinesia were similar for both (36-39% mild, 3-6% moderate, and 0% severe). Median time-to-ON was 25.0 min following carbidopa/levodopa + CVT-301 and 35.5 min following carbidopa/levodopa + placebo (P = 0.26). At 30 min, more patients had turned ON following carbidopa/levodopa + CVT-301 administration (66.7%), compared with carbidopa/levodopa + placebo (44.5%) (P = 0.040). CONCLUSION: Single doses of CVT-301 84 mg administered with oral carbidopa/levodopa for early morning OFF symptoms were well-tolerated, with no notable safety concerns.

Best practices for the use of itraconazole as a replacement for ketoconazole in drug-drug interaction studies.

Ketoconazole has been widely used as a strong cytochrome P450 (CYP) 3A (CYP3A) inhibitor in drug-drug interaction (DDI) studies. However, the US Food and Drug Administration has recommended limiting the use of ketoconazole to cases in which no alternative therapies exist, and the European Medicines Agency has recommended the suspension of its marketing authorizations because of the potential for serious safety concerns. In this review, the Innovation and Quality in Pharmaceutical Development's Clinical Pharmacology Leadership Group (CPLG) provides a compelling rationale for the use of itraconazole as a replacement for ketoconazole in clinical DDI studies and provides recommendations on the best practices for the use of itraconazole in such studies. Various factors considered in the recommendations include the choice of itraconazole dosage form, administration in the fasted or fed state, the dose and duration of itraconazole administration, the timing of substrate and itraconazole coadministration, and measurement of itraconazole and metabolite plasma concentrations, among others. The CPLG's recommendations are based on careful review of available literature and internal industry experiences.

Phase 1 trial of a 13-valent pneumococcal conjugate vaccine in healthy adults.

In a Phase 1 study, 15 healthy subjects were randomized to receive a 13-valent pneumococcal conjugate vaccine (PCV13) and 15 to receive a 23-valent pneumococcal polysaccharide vaccine (23vPS). Antibody responses were measured immediately before and approximately one month after vaccination. Serotype-specific antibodies were measured using an enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) and an opsonophagocytic assay (OPA) for functional antibodies. PCV13 was as immunogenic or more immunogenic than 23vPS and was well tolerated.