Immunogenicity of golimumab and its clinical relevance in patients with rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis.

OBJECTIVE: Golimumab immunogenicity was extensively studied during clinical development. As anti-drug antibody (ADA) detection with the standard bridging EIA (original-EIA) can yield false-negative results or underestimate ADA incidence and titres due to drug interference, a more sensitive assay was needed to determine clinical impact. METHODS: A highly sensitive drug-tolerant EIA (DT-EIA) was developed and cross-validated against the original-EIA. Samples from phase-3 subcutaneous golimumab rheumatological trials (GO-FORWARD-rheumatoid arthritis, GO-REVEAL-psoriatic arthritis, GO-RAISE-ankylosing spondylitis) were then retested. Associations between ADAs and golimumab pharmacokinetics, efficacy and safety were assessed. RESULTS: The DT-EIA was more sensitive than the original-EIA and capable of detecting ADAs amid golimumab concentrations far exceeding those in immunogenicity test samples. Consequently, an 8-fold increase in the incidence of ADAs was observed with the DT-EIA (31.7%) vs original-EIA (4.1%) in the studies. Most ADA-positive patients identified by the DT-EIA had lower antibody titres, while most with higher titres were previously identified as ADA-positive by the original-EIA. With the DT-EIA, ADA-positive patients generally had lower trough serum golimumab concentrations than ADA-negative patients; however, ADA impact on serum golimumab concentrations was more notable at higher ADA titres (⩾100). No impact of ADAs on clinical efficacy or injection-site reactions was evident. CONCLUSION: ADA incidence was expectedly higher using the DT-EIA vs original-EIA; newly detected ADAs were characterized mostly by low titres, with no impact on clinical efficacy or injection-site reactions, consistent with previously observed original-EIA results. Golimumab immunogenicity with the DT-EIA is consistent with existing knowledge regarding the clinical relevance of ADAs detected with the original-EIA in patients with rheumatological disorders. TRIAL REGISTRATION: NCT00264550, NCT00265096, NCT00265083.

Two prospective, multicenter studies for the identification of biomarker signatures for early detection of pulmonary hypertension (PH): The CIPHER and CIPHER-MRI studies.

A blood test identifying patients at increased risk of pulmonary hypertension (PH) could streamline the investigative pathway. The prospective, multicenter CIPHER study aimed to develop a microRNA-based signature for detecting PH in breathless patients and enrolled adults with a high suspicion of PH who had undergone right heart catheterization (RHC). The CIPHER-MRI study was added to assess the performance of this CIPHER signature in a population with low probability of having PH who underwent cardiac magnetic resonance imaging (cMRI) instead of RHC. The microRNA signature was developed using a penalized linear regression (LASSO) model. Data were modeled both with and without N-terminal pro-brain natriuretic peptide (NT-proBNP). Signature performance was assessed against predefined thresholds (lower 98.7% CI bound of ≥0.73 for sensitivity and ≥0.53 for specificity, based on a meta-analysis of echocardiographic data), using RHC as the true diagnosis. Overall, 926 CIPHER participants were screened and 888 were included in the analysis. Of 688 RHC-confirmed PH cases, approximately 40% were already receiving PH treatment. Fifty microRNA (from 311 investigated) were algorithmically selected to be included in the signature. Sensitivity [97.5% CI] of the signature was 0.85 [0.80-0.89] for microRNA-alone and 0.90 [0.86-0.93] for microRNA+NT-proBNP, and the corresponding specificities were 0.33 [0.24-0.44] and 0.28 [0.20-0.39]. Of 80 CIPHER-MRI participants with evaluable data, 7 were considered PH-positive by cMRI whereas 52 were considered PH-positive by the microRNA signature. Due to low specificity, the CIPHER miRNA-based signature for PH (either with or without NT-proBNP in model) did not meet the prespecified diagnostic threshold for the primary analysis.

Tolerability, pharmacokinetics and night-time effects on postural sway and critical flicker fusion of gaboxadol and zolpidem in elderly subjects.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: Body sway increases in older adults and may lead to an increase in the risk of falling. The problem of impaired stability in the elderly may be compounded by the use of hypnotics, which have been associated with an increased risk of next-day falls as well as drowsiness. The potential adverse effects of hypnotic drugs on steadiness may be exacerbated during the night, in the event that an individual needs to get out of bed. WHAT THIS STUDY ADDS: This study examines the effects of gaboxadol (an investigational treatment for insomnia), zolpidem (a current hypnotic included as an active control) and placebo on body sway and attention/information processing ability following bedtime dosing in elderly subjects who were woken during the night for assessments. Zolpidem and gaboxadol increased body sway at various time points during the night relative to placebo; at 1.5 h post dose, the time of peak concentrations of both drugs, gaboxadol produced less impairment than zolpidem. Compared with placebo, neither gaboxadol nor zolpidem impaired attention/information-processing ability as assessed by critical flicker fusion. AIMS: To evaluate tolerability, pharmacokinetics and night-time effects on body sway and critical flicker fusion (CFF) of gaboxadol following bedtime dosing in healthy elderly subjects. METHODS: Subjects (17 women, seven men) aged 65-75 years received gaboxadol 10 mg, zolpidem 5 mg (active control) or placebo at 22.00 h in a three-period, randomized, double-blind crossover study. They were awakened during the night for evaluation of body sway and CFF. Pharmacokinetics of gaboxadol were assessed during a fourth single-blind treatment period. Adverse events were recorded throughout the study. RESULTS: The number of subjects with adverse events was 14 for gaboxadol 10 mg, seven for zolpidem and nine for placebo; most were mild or moderate in intensity. Two women discontinued the study following gaboxadol; one vomited and one experienced a severe vasovagal syncope after venepuncture. Mean gaboxadol t(max) was 2 h, t((1/2)) was 1.7 h, AUC(0-infinity) was 430 ng.h ml(-1) and C(max) was 139 ng ml(-1). At 1.5 h and 4 h post dose, zolpidem increased body sway relative to placebo (P < 0.01). Gaboxadol increased body sway at 4 h (P < 0.001) and 8 h (P < 0.05) relative to placebo. At 1.5 h, the time point closest to peak drug concentrations, zolpidem increased body sway compared with gaboxadol (P < 0.01). Gaboxadol and zolpidem had no effects on CFF vs. placebo. CONCLUSIONS: A bedtime dose of gaboxadol 10 mg was generally well tolerated. Changes in body sway at 1.5 h after bedtime dosing were smaller with gaboxadol 10 mg than with zolpidem 5 mg, whereas changes were similar at 4 h for both treatments and returned to near baseline at 8 h.

Next-day residual effects of gaboxadol and flurazepam administered at bedtime: a randomized double-blind study in healthy elderly subjects.

OBJECTIVE: To evaluate the next-day residual effects of the novel hypnotic, gaboxadol, following bedtime dosing in healthy elderly subjects. METHODS: Healthy women (N = 15) and men (N = 10) aged 65-79 years received a single bedtime (22:00 h) dose of gaboxadol 10 mg, flurazepam 30 mg (positive control), and placebo in a randomized, double-blind, crossover study. Measures of information processing and psychomotor performance (choice reaction time, critical flicker fusion, digit symbol substitution, compensatory tracking, body sway), memory (immediate and delayed word recall), and daytime sleepiness (Multiple Sleep Latency Test), as well as subjective ratings (line analog rating scales, Leeds Sleep Evaluation Questionnaire), were obtained starting at 07:00 h the following morning. Adverse events were recorded. RESULTS: Gaboxadol did not show next-day impairments versus placebo on any pharmacodynamic measures whereas the positive control, flurazepam, did show impairments versus placebo on most measures. Gaboxadol showed improvements versus placebo on some measures including subjective rating of next-day alertness/clumsiness on the Leeds Sleep Evaluation Questionnaire. Gaboxadol was generally well-tolerated; there were no serious adverse experiences and no subjects discontinued due to an adverse experience. CONCLUSIONS: A single oral bedtime dose of gaboxadol 10 mg did not have next-day residual effects in healthy elderly subjects, as measured by a range of pharmacodynamic assessments, in contrast to the clear impairments produced by flurazepam 30 mg.

Immunogenicity of Golimumab and its Clinical Relevance in Patients With Ulcerative Colitis.

BACKGROUND: Antidrug antibody (ADA) detection with standard bridging enzyme immunoassays (EIA) can yield false-negative results or underestimate titers through drug interference. A more sensitive assay was needed to determine clinical impact of antigolimumab antibodies. METHODS: A high-sensitivity, drug-tolerant EIA (DT-EIA) was developed and cross-validated against the original EIA, and samples from induction/maintenance studies in golimumab-treated patients with ulcerative colitis were analyzed for ADAs using both methods. Immunogenicity results were compared, and pharmacokinetic, efficacy, and safety associations were evaluated. RESULTS: An 8-fold increase in ADA-positive patients (21.8% DT-EIA vs 2.8% EIA) reflected DT-EIA improved sensitivity and drug tolerance. Most newly detected ADA-positive patients (using DT-EIA) had low antibody titers, whereas most with high antibody titers were ADA-positive with original EIA. With DT-EIA, week 44 median trough serum golimumab concentrations among ADA-positive patients were approximately half vs ADA-negative (0.51 vs 0.85 µg/mL [50 mg q4w]; 0.85 vs 1.60 µg/mL [100 mg q4w]). Antidrug antibody impact on golimumab concentrations was more notable at titers ≥1:100. During induction, ADAs had no notable impact on efficacy. During maintenance, proportions of patients maintaining clinical response through week 54 were lower using DT-EIA: 38.1% ADA-positive and 52.8% ADA-negative. Antidrug antibody status had no impact on injection-site reaction incidence. CONCLUSIONS: A more sensitive DT-EIA identified higher proportions of ADA-positive patients. A trend of decreasing drug concentrations with increasing ADA titers was observed. Pharmacokinetic impact was better elucidated with DT-EIA. Although development of ADA did not preclude efficacy, a trend toward decreased efficacy in ADA-positive vs ADA-negative patients was observed during maintenance treatment. Antidrug antibody status did not impact safety.

Pharmacodynamic effects of suvorexant and zolpidem on EEG during sleep in healthy subjects.

The objective of this study was to evaluate sleep electrophysiology in healthy subjects after bedtime administration of therapeutic doses of two insomnia treatments - the orexin receptor antagonist suvorexant or the GABAergic agonist zolpidem. Eighteen healthy men received single bedtime doses of suvorexant 20mg, zolpidem 10mg, or placebo in a double-blinded, randomized, balanced 3-period crossover study. EEG power spectral densities during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep were recorded in a polysomnography (PSG) laboratory using a 19-lead EEG recording array. Spectral density was analyzed for each lead for frequencies between 1-32Hz. During NREM and REM sleep, zolpidem treatment reduced spectral density across theta and alpha frequency bands in all leads. In contrast, suvorexant had no significant effects on spectral density in any frequency band during NREM sleep, and modestly increased spectral density in the theta frequency band during REM sleep. Although the study was not designed to detect effects on PSG sleep endpoints in healthy subjects, both suvorexant and zolpidem increased mean total sleep time and sleep efficiency. Zolpidem reduced latency to persistent sleep whereas suvorexant did not. Suvorexant decreased wake after sleep onset, whereas zolpidem did not. These findings suggest that EEG power spectral density profile after administration of suvorexant in healthy subjects more closely approximates placebo sleep physiology than after zolpidem treatment.

A randomized, crossover, placebo-controlled clinical trial to assess the sensitivity of the CRCDS Mini-Sim to the next-day residual effects of zopiclone.

OBJECTIVES: We sought to validate Cognitive Research Corporation's Driving Simulator (CRCDS Mini-Sim) for studies of drug safety with respect to driving ability. METHODS: A total of 30 healthy subjects were randomized to receive placebo or 7.5 mg zopiclone, a hypnotic known to impair driving, in random order during the 2 treatment periods of a 2 period crossover design. RESULTS: Evening administration of 7.5 mg zopiclone increased next-day standard deviation of lateral lane position (SDLP) by 2.62 cm on average compared with evening administration of placebo, and caused significant effects on symmetry analysis. The magnitude of the change in SDLP is highly similar to changes previously observed using on-the-road driving methods. CONCLUSIONS: Further validation of the CRCDS Mini-Sim is warranted to develop this platform for drug safety studies.

Human positron emission tomography studies of brain neurokinin 1 receptor occupancy by aprepitant.

BACKGROUND: Aprepitant is a highly selective substance P (neurokinin 1 [NK(1)] receptor) antagonist that significantly improves the pharmacotherapy of acute and delayed highly emetogenic chemotherapy-induced nausea and vomiting, probably through an action in the brain stem region of the central nervous system. Here, we report the use of positron emission tomography imaging with the NK(1) receptor binding-selective tracer [(18)F]SPA-RQC to determine the levels of central NK(1) receptor occupancy achieved by therapeutically relevant doses of aprepitant in healthy humans. METHODS: Two single-blind, randomized, placebo-controlled studies in healthy subjects were performed. The first study evaluated the plasma concentration-occupancy relationships for aprepitant dosed orally at 10, 30, 100, or 300 mg, or placebo (n = 12). The second study similarly evaluated oral aprepitant 30 mg and placebo (n = 4). In each study, dosing was once daily for 14 consecutive days. Data from both studies were combined for analyses. The ratio of striatal/cerebellar [(18)F]SPA-RQ (high receptor density region/reference region lacking receptors) was used to calculate trough receptor occupancy 24 hours after the last dose of aprepitant. RESULTS: Brain NK(1) receptor occupancy increased after oral aprepitant dosing in both a plasma concentration-related (r =.97; 95% confidence interval [CI] =.94-1.00, p <.001) and a dose-related (r =.94; 95% CI =.86-1.00, p <.001) fashion. High (> or =90%) receptor occupancy was achieved at doses of 100 mg/day or greater. The plasma concentrations of aprepitant that achieved 50% and 90% occupancy were estimated as approximately 10 ng/mL and approximately 100 ng/mL, respectively. CONCLUSIONS: Positron emission tomography imaging with [(18)F]SPA-RQ allows brain NK(1) receptor occupancy by aprepitant to be predicted from plasma drug concentrations and can be used to guide dose selection for clinical trials of NK(1) receptor antagonists in central therapeutic indications.

Effects of the neurokinin1 receptor antagonist aprepitant on the pharmacokinetics of dexamethasone and methylprednisolone.

BACKGROUND: Aprepitant is a neurokinin(1) receptor antagonist that, in combination with a corticosteroid and a 5-hydroxytryptamine(3) receptor antagonist, has been shown to be very effective in the prevention of chemotherapy-induced nausea and vomiting. At doses used for the management of chemotherapy-induced nausea and vomiting, aprepitant is a moderate inhibitor of cytochrome P4503A4 and may be used in conjunction with corticosteroids such as dexamethasone and methylprednisolone, which are substrates of cytochrome P4503A4. The effects of aprepitant on the these 2 corticosteroids were evaluated. METHODS: Study 1 was an open-label, randomized, incomplete-block, 3-period crossover study with 20 subjects. Treatment A consisted of a standard oral dexamethasone regimen for chemotherapy-induced nausea and vomiting (20 mg dexamethasone on day 1, 8 mg dexamethasone on days 2 to 5). Treatment B was used to examine the effects of oral aprepitant (125 mg aprepitant on day 1, 80 mg aprepitant on days 2 to 5) on the standard dexamethasone regimen. Treatment C was used to examine the effects of aprepitant on a modified dexamethasone regimen (12 mg dexamethasone on day 1, 4 mg dexamethasone on days 2 to 5). All subjects also received 32 mg ondansetron intravenously on day 1 only. Study 2 was a double-blind, randomized, placebo-controlled, 2-period crossover study with 10 subjects. Subjects in one group received a regimen consisting of 125 mg methylprednisolone intravenously on day 1 and 40 mg methylprednisolone orally on days 2 to 3. Subjects in the other group received oral aprepitant (125 mg aprepitant on day 1, 80 mg aprepitant on days 2 to 3) in addition to the methylprednisolone regimen. RESULTS: In study 1, the area under the concentration-time curve from 0 to 24 hours (AUC(0-24)) of oral dexamethasone on days 1 and 5 after the standard dexamethasone plus ondansetron regimen (treatment A) was increased 2.2-fold (P <.010) with coadministration of aprepitant (treatment B). Coadministration of aprepitant with the modified dexamethasone plus ondansetron regimen (treatment C) resulted in an AUC0-24 for dexamethasone similar to that observed after the standard dexamethasone plus ondansetron regimen (treatment A). In study 2, aprepitant increased the AUC0-24 of intravenous methylprednisolone 1.3-fold on day 1 (P <.010) and increased the AUC0-24 of oral methylprednisolone 2.5-fold on day 3 (P <.010). CONCLUSIONS: Coadministration of aprepitant with dexamethasone or methylprednisolone resulted in increased plasma concentrations of the corticosteroids. These findings suggest that the dose of these corticosteroids should be adjusted when given with aprepitant.

Evaluation of potential inductive effects of aprepitant on cytochrome P450 3A4 and 2C9 activity.

The NK(1) receptor antagonist aprepitant (EMEND(R)), developed for use in combination with a 5HT(3) receptor antagonist and a corticosteroid to prevent highly emetogenic chemotherapy-induced nausea and vomiting (CINV), has been shown to have a moderate inhibitory effect as well as a possible inductive effect on cytochrome P450 (CYP) 3A4. Aprepitant has been noted to produce modest decreases in plasma S(-)-warfarin concentrations, suggesting potential induction of CYP2C9. Because metabolism of some chemotherapeutic agents may involve CYP3A4, the potential inductive effect of the CINV dosing regimen of aprepitant on this metabolic pathway was evaluated using intravenous midazolam, a sensitive probe substrate of CYP3A4. The time course of induction of CYP2C9 by aprepitant was also evaluated using oral tolbutamide, a probe substrate of CYP2C9. In this double-blind, randomized, placebo-controlled, single-center study, 24 healthy subjects were randomized (12 subjects per group) to receive either an aprepitant 3-day regimen (aprepitant 125 mg p.o. on day 1 and aprepitant 80 mg p.o. on days 2 and 3) or matching placebo. All subjects also received probe drugs (midazolam 2 mg i.v. and tolbutamide 500 mg p.o.) once prior to aprepitant dosing (baseline) and again on days 4, 8, and 15. The ratio (aprepitant/placebo) of the geometric mean area under the plasma concentration curve (AUC) fold-change from baseline for midazolam was 1.25 on day 4 (p < 0.01), 0.81 on day 8 (p < 0.01), and 0.96 on day 15 (p = 0.646). The ratio (aprepitant/placebo) of the geometric mean AUC fold-change from baseline for tolbutamide was 0.77 on day 4 (p < 0.01), 0.72 on day 8 (p < 0.001), and 0.85 on day 15 (p = 0.05). Assessed using intravenous midazolam as a probe, aprepitant 125/80 mg p.o. administered over days 1 to 3 produced clinically insignificant weak inhibition (day 4) and induction (day 8) of CYP3A4 activity and no effect on CYP3A4 activity on day 15. Assessed using oral tolbutamide as a probe, the aprepitant regimen also produced modest induction of CYP2C9 activity on days 4 and 8, which resolved nearly to baseline by day 15. Thus, the aprepitant regimen for CINV results in modest, transient induction of CYPs 3A4 and 2C9 in the 2 weeks following administration.

Placebo- and amitriptyline-controlled evaluation of central nervous system effects of the NK1 receptor antagonist aprepitant and intravenous alcohol infusion at pseudo-steady state.

Recent interest in NK1 receptor antagonists has focused on a potential role in the treatment of drug addiction and substance abuse. In the present study, the potential for interactions between the NK1 receptor antagonist aprepitant and alcohol, given as an infusion at a target level of 0.65 g/L, was evaluated. Amitriptyline was included as positive control to provide an impression of the profile of central nervous system (CNS) effects. In a double-blind, randomized, placebo- and amitriptyline-controlled study, the pharmacokinetics and CNS effects of aprepitant and alcohol were investigated in 16 healthy volunteers. Cognitive and psychomotor function tests included the visual verbal learning test (VVLT), Bond and Lader visual analogue scales (VAS), digit symbol substitution test (DSST), visual pattern recognition, binary choice reaction time, critical flicker fusion (CFF), body sway, finger tapping, and adaptive tracking. Alcohol impaired finger tapping and body sway. Amitriptyline impaired DSST performance, VAS alertness, CFF, body sway, finger tapping, and adaptive tracking. No impairments were found after administration of aprepitant. Co-administration of aprepitant with alcohol was generally well tolerated and did not cause significant additive CNS effects, compared with alcohol alone. Therefore, our study found no indications for clinically relevant interactions between aprepitant and alcohol.

Double-blind crossover study to assess potential differences in cytochrome P450 3A4 activity in healthy subjects receiving ondansetron plus dexamethasone, with and without aprepitant.

PURPOSE: Because glucocorticoids and the neurokinin-1 receptor antagonist aprepitant influence CYP3A4 activity, this study assessed whether aprepitant added to a 5-HT(3) antagonist and glucocorticoid would affect CYP3A4 induction. METHODS: In this double-blind, 2-period crossover study, 12 subjects were randomized to receive a triple regimen (oral aprepitant [A] 125 mg, intravenous ondansetron [O] 32 mg, and oral dexamethasone [D] 12 mg day 1; A 80 mg and D 8 mg days 2-3; D 8 mg day 4) in 1 of 2 periods, and a dual regimen (O 32 mg and D 20 mg day 1; D 8 mg bid days 2-4); the D dose was adjusted to account for known dexamethasone/aprepitant interaction. Oral (2 mg) and intravenous (1 mg) stable isotope ((13)C(5) (15)N(1))-labeled midazolam were simultaneously given as probes on days -1, 6, 8, 15, and 22 of each period. If the a priori 90% confidence interval for the day 6 geometric mean oral midazolam AUC(0-∞) ratio (triple/dual regimen) of fold-change from baseline was above 0.5, it would be concluded that there was no clinically meaningful between-regimen difference in CYP3A4 activity. RESULTS: Day 6 oral midazolam AUC(0-∞) geometric mean fold-change from baseline was 0.84 (0.30-1.58 with A, 0.46-1.69 without A). The ratio of geometric mean oral midazolam AUC(0-∞) fold-changes was 1.00 (90% confidence interval 0.80, 1.25). CONCLUSIONS: Aprepitant plus a 5-HT(3) antagonist and dexamethasone is unlikely to have a significant additional inductive effect on CYP3A4 activity beyond that of the dual regimen.

An enhanced bunionectomy model as a potential tool for early decision-making in the development of new analgesics.

BACKGROUND: bunionectomy has been used as a model of postoperative pain for opioids and nonsteroidal anti-inflammatory drugs/cyclooxygenase-2 inhibitors with a fast onset of analgesia. The present study was conducted to assess whether the utility of the model can be broadened in assessing the efficacy of analgesics with diverse mechanisms and pharmacokinetic profiles in drug development and to enhance the sensitivity of a bunionectomy model. METHODS: this was a single center, randomized, double-blind, placebo-controlled, three-arm, parallel group methodology study to evaluate the effects of pregabalin and naproxen sodium on postoperative pain following bunionectomy. Patients (n=100) were randomized 1:1:1 to three treatments (administered 1 hour before and at defined intervals after surgery): pregabalin 300 mg before surgery and 150 mg every 8 hours; naproxen sodium 550 mg before surgery and 550 mg every 12 hours; or placebo in a double-dummy fashion. Primary endpoints were patient-controlled analgesic (PCA) hydromorphone consumption and the time to first PCA hydromorphone use postsurgery over 24 hours. RESULTS: of the 100 patients randomized, 96 completed the study. Relative to placebo, pregabalin and naproxen sodium, respectively, reduced PCA hydromorphone consumption by 51% (P=0.005) and 65% (P<0.001) and increased the median time to first use of PCA hydromorphone by 1.5 hours (P=0.004) and 3.7 hours (P<0.001). Both drugs significantly (P<0.050) decreased use of oral opioid rescue medication over 24-48 hours postsurgery relative to placebo. Although there were no statistically significant differences between naproxen sodium and pregabalin in opioid consumption and global evaluation of medication, overall naproxen sodium appeared to be more effective at reducing pain. CONCLUSIONS: the model provided a sensitive method for evaluating efficacy of compounds with diverse mechanisms and pharmacokinetic profiles. The robustness of the enhanced pain model renders bunionectomy pain a valuable tool to assess novel analgesic compounds in small numbers of subjects early in drug development.