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A small library of 3-[(4-hydroxycarbamoylphenyl)aminomethyl]benzothiophenes was prepared and assessed as a novel class of HDAC6 inhibitors, leading to the identification of three representatives as potent and selective HDAC6 inhibitors. Further tests with regard to inflammatory responses indicated that HDAC6 inhibition can be uncoupled from transcriptional inhibition at the level of activated NF-κB, AP-1, and GR.

Summary: Purpose: To characterize the possible pharmacokinetic interaction between the new antiepileptic and CNS drug RWJ-333369 and carbamazepine (CBZ) following multiple dosing in healthy subjects. Methods: In an 8-week, open-label, sequential design study, 24 healthy adults received multiple-dose RWJ-333369 alone (5 days 250 mg q12h; 5 days 500 mg q12h), then after a 4-day washout, multiple-dose CBZ alone (3 days 100 mg q12h; 3 days 200 mg q12h; 22 days 300 mg q12h), and then combination of CBZ (300 mg q12h), and RWJ-333369 (5 days 250 mg q12h; 5 days 500 mg q12h). Results: At steady-state following multiple dosing, RWJ-333369 peak plasma concentration (Cmax) and area under the concentration-time-curve within the dosing interval (AUCss) increased in proportion to dose. The Cmax and AUCss of CBZ were similar when given alone or concomitantly with RWJ-333369. The 90% confidence intervals for the ratio of CBZ Cmax and AUCss with/without RWJ-333369 were: 94–104% and 95–104%, respectively (well within the equivalence range of 80–125%). When RWJ-333369 was administered with CBZ, its mean (SD) oral clearance increased from 3.2 L/h to 4.9 L/h and consequently its mean half-life was shortened from 10.4 (1.9) h to 7.4 (1.2) h, and mean AUCss and Cmax were reduced by 37% and 30%, respectively. Conclusions: There was no effect of multiple-dose RWJ-333369 on CBZ pharmacokinetics. CBZ induced RWJ-333369 clearance, resulting in shortened half-life and decreased exposure (AUCss) and Cmax. Concomitant administration of RWJ-333369 with CBZ was generally safe and tolerated.

The primary objective of this study was to identify intravenous regimens of tipifarnib that would mimic the systemic exposure obtained after the current twice-daily oral administration of tipifarnib. After determination of an intravenous dose that 6 subjects with advanced cancer could tolerate, another 26 subjects were randomly assigned to receive 3 consecutive 4-day regimens of tipifarnib with different treatment sequences: a 100-mg 2-hour intravenous infusion, 200-mg oral administration twice daily, and a 200-mg/d continuous intravenous infusion. The systemic exposure to tipifarnib was comparable among these 3 regimens. The plasma concentration-time profile of 2-hour intravenous infusion more closely resembled the oral administration than did the continuous infusion. Glucuronidation is a metabolic pathway for tipifarnib with concentrations of the glucuronide conjugate greatly exceeding the parent compound after oral and intravenous administration. Analysis of plasma metabolites indicated that tipifarnib also undergoes dealkylation and loss of the imidazole group.

To assess the steady-state galantamine (GAL) bioavailability of the extended-release 24-mg qd capsule (GAL-ER) with and without food and to evaluate the relative bioavailability of GAL-ER with the immediate-release 12-mg bid tablet (GAL-IR) at steady state.This was a single-center, open-label, randomized, 3-way crossover study in 24 healthy volunteers (12 males and 12 females) aged 18 to 45 years. After 7 days of GAL-ER 8 mg qd each morning and 7 days of GAL-ER 16 mg qd each morning, subjects received the following treatments in randomized, crossover order (7 days each): GAL-ER 24 mg qd each morning (fasted before Day 7 morning dose), GAL-ER 24 mg qd each morning (fed before Day 7 morning dose), and GAL-IR 12 mg bid (fasted before Day 7). Pharmacokinetic parameters of GAL at steady state were determined after morning intake on Day 7 of each treatment week. Safety evaluations included adverse event (AE) reporting, physical examination, clinical laboratory tests, vital signs, and electrocardiography.The treatment ratios of area under the plasma concentration-time curve of GAL from time 0-24 h post-dosing (AUC24 h), peak plasma concentration (Cmax), and pre-dose plasma concentration (Cmin) for GAL-ER fed/fasting were 105%, 112%, and 103%, respectively. The treatment ratios and 90% confidence intervals for all above mentioned pharmacokinetic parameters demonstrated bioequivalence (with the range of 80-125%), indicating that food had no effect on GAL-ER bioavailability. As anticipated, GAL-ER (fasting) had mean AUC24 h similar to GAL-IR (fasting), with lower Cmax (63 ng/mL vs 84 ng/mL) and longer time to reach Cmax (4.4 h vs 1.2 h). The treatment ratios and 90% confidence intervals for both AUC24 h and Cmin demonstrated bioequivalence (within the range of 80-125%). The treatment ratio for Cmax was 75.7%, indicating a 24% lower Cmax for GAL-ER than for GAL-IR. In this study, GAL-ER was safe and well tolerated with or without food and was comparable to the GAL-IR formulation.Food had no effect on the GAL bioavailability of GAL-ER at steady state. GAL-ER was bioequivalent to GAL-IR with respect to AUC24 h and Cmin.

To evaluate the effect of multiple doses of memantine on the pharmacokinetics of galantamine and to assess the safety and tolerability of galantamine with adjunctive memantine treatment, an open-label, single-center, drug interaction study was conducted in 16 healthy adults. Subjects received an 8-mg dose of galantamine extended release once daily during week 1 and a 16-mg dose of galantamine extended release once daily during week 2. During weeks 3 and 4, they received a 16-mg dose of galantamine extended release once daily and a 10-mg dose of memantine twice daily, except on days 1 and 2 of week 3, when memantine was given as 10 mg once daily. The pharmacokinetic profile and parameters of galantamine at steady state were similar after administration of a 16-mg dose of galantamine once daily alone and after administration with a 10-mg dose of memantine twice daily. Galantamine 16 mg once daily with adjunctive memantine 10 mg twice daily was well tolerated and safe in healthy subjects.

The objective of this study was to compare the pharmacokinetics and safety of galantamine in subjects with hepatic impairment with those in healthy subjects. This was an open-label study in which a single oral 4-mg dose of galantamine was administered to volunteers with mild (Child-Pugh score of 5-6, n = 8), moderate (Child-Pugh score of 7-9, n = 8), or severe hepatic impairment (Child-Pugh score of 10-15, n = 1) and to healthy, matched control subjects (n = 8). Galantamine pharmacokinetics and safety (adverse events, laboratory test results, electrocardiograms, vital signs, and cardiac events) were assessed over 6 days after administration of galantamine. The pharmacokinetic parameters of galantamine were similar in subjects with mild hepatic impairment compared with healthy controls. Compared with the healthy control group, subjects with moderate hepatic impairment showed relative increases in the area under the plasma-concentration curve from zero to infinity (AUC0-infinity) (+33%) and terminal half-life (t1/2) (+30%) (p = 0.051 and p = 0.003, respectively), a 23% relative decrease in total plasma clearance (p = 0.061), and a small but significant relative increase in the fraction of free plasma galantamine (p = 0.009). Galantamine was well tolerated by all subjects. There were no serious adverse events (AEs) or premature withdrawals from the study because of AEs. Reported AEs were headache (three cases), nausea (one case), and paresthesia (one case). There were no clinically relevant changes in clinical laboratory findings, vital signs, and electrocardiograms. Low patient recruitment (n = 1) precluded statistical analysis of galantamine pharmacokinetics and safety in severe hepatic impairment. It was concluded that the pharmacokinetics of galantamine in subjects with mild hepatic impairment was similarto those in healthy subjects. In subjects with moderate hepatic impairment, galantamine clearance was decreased by approximately 23% compared with normal volunteers. Galantamine was also well tolerated and appeared to be safe in subjects with mild ormoderate hepatic impairment. Based on the study results, it appears that it would not be necessary to adjust doses of galantamine during administration to subjects with mild hepatic impairment. In subjects with moderately impaired hepatic function, dose titration should proceed cautiously. Unfortunately, difficulties with patient recruitment did not allow adequate assessment of the safety of galantamine in subjects with severe hepatic impairment in this study. Therefore, the use of galantamine in subjects with severe hepatic impairment is not recommended.

Adequate monitoring of internal standard (IS) response across an analytical run and identification of anomalies is now a common expectation. However, the means to conduct this assessment in an appropriate manner is unclear and differs widely between laboratories. A European Bioanalysis Forum (EBF) topic team was formed to survey current practices within European Bioanalysis Forum member companies and to recommend a best practice approach for dealing with IS response variability.

The times when all bioanalytical work was supported in-house are long behind us. In the modern bioanalytical laboratory, workload is divided between in-house support and outsourcing to contract research organizations. This paper outlines the outsourcing strategy of the Janssen-regulated bioanalytical group. Keeping the knowledge of the assay and the compound internally is a cornerstone of this strategy and is a driver for balancing the workload between the internal laboratory and contract laboratories. The number of contract laboratories that are being used is limited and criteria for selecting laboratories are discussed. Special attention is paid to the experience with outsourcing clinical studies to China.

Drug-drug interactions between canagliflozin, a sodium glucose co-transporter 2 inhibitor, and glyburide, metformin, and simvastatin were evaluated in three phase-1 studies in healthy participants. In these open-label, fixed sequence studies, participants received: Study 1-glyburide 1.25 mg/day (Day 1), canagliflozin 200 mg/day (Days 4-8), canagliflozin with glyburide (Day 9); Study 2-metformin 2,000 mg/day (Day 1), canagliflozin 300 mg/day (Days 4-7), metformin with canagliflozin (Day 8); Study 3-simvastatin 40 mg/day (Day 1), canagliflozin 300 mg/day (Days 2-6), simvastatin with canagliflozin (Day 7). Pharmacokinetic parameters were assessed at prespecified intervals. Co-administration of canagliflozin and glyburide did not affect the overall exposure (maximum plasma concentration [Cmax ] and area under the plasma concentration-time curve [AUC]) of glyburide and its metabolites (4-trans-hydroxy-glyburide and 3-cis-hydroxy-glyburide). Canagliflozin did not affect the peak concentration of metformin; however, AUC increased by 20%. Though Cmax and AUC were slightly increased for simvastatin (9% and 12%) and simvastatin acid (26% and 18%) following coadministration with canagliflozin, compared with simvastatin administration alone; however, no effect on active 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitory activity was observed. There were no serious adverse events or hypoglycemic episodes. No drug-drug interactions were observed between canagliflozin and glyburide, metformin, or simvastatin. All treatments were well-tolerated in healthy participants.

The A8 Global Harmonization Team focused on the documentation needed to support both small and large molecule bioanalysis. Current regulatory requirements were compiled and compared. The scope of the team’s discussions included the validation report, the bioanalytical report, study plans, raw data, and bioanalytical summaries for the common technical document (CTD). A common high-level table of contents for method validation and sample analysis reports is proposed. Suggestions have been made as to how the CTD can be standardized to improve usability and review. Additional comments have been made on reports of failure investigations, study plans, and raw data documentation. The recommendation is that no prescriptive guidelines are required in these areas but should be led by good scientific practices subject to particular circumstances.

Consensus engineering, which is replacing amino acids by the most frequently occurring one at their positions in a multiple sequence alignment (MSA), is a known strategy to increase the stability of a protein. The application of this concept to the entire sequence of an enzyme, however, has been tried only a few times mainly because of the problems determining the consensus in highly variable regions. We show that this problem can be solved by replacing such problematic regions by the corresponding sequence of the natural homologue closest to the consensus. When one or a few sub-families are overrepresented in the MSA the consensus sequence is a biased representation of the sequence space. We examine the influence of this bias by constructing three consensus sequences using different MSAs of sucrose phosphorylase (SP). Each consensus enzyme contained about 70 mutations compared to its closest natural homologue and folded correctly and displayed activity on sucrose. Correlation analysis revealed that the family's co-evolution network was kept intact, which is one of the main advantages of full-length consensus design. The consensus enzymes displayed an "average" thermostability, that is, one that is higher than some but not all known representatives. We cautiously present practical rules for the design of consensus sequences, but warn that the measure of success depends on which natural enzyme is used as point of comparison.

2-(4-Chloro-2-cyano-2-phenylbutyl)aziridines were employed for the one-step stereoselective construction of both endo- and exo-2-aminomethyl-4-phenyl-1-azabicyclo[2.2.1]heptanes as new azaheterobicyclic scaffolds via a double LiAlH(4)-induced reductive cyclization protocol. Antiplasmodial assessment of these 1-azabicyclo[2.2.1]heptanes revealed moderate to good activities in the micromolar range, with the exo-isomers being the most promising structures. Furthermore, the proposed mode of action was supported by ligand docking studies, pointing to a strong binding interaction with the enzyme plasmepsin II.

Many patients with chronic pain, including those with chronic whiplash-associated disorders (WAD), show features of central sensitization. Randomized trials examining whether treatments are able to influence the process of central sensitization in patients with chronic WAD are emerging. Therefore, the present study aimed at examining whether acupuncture results in activation of endogenous analgesia and relief in symptoms in patients with chronic WAD.In this randomized crossover pilot trial with blinded assessors, each patient (n = 39) received two treatment sessions of identical duration, with acupuncture and relaxation therapy randomly crossed over in visit 2. Primary outcome measurement included immediate activation of endogenous analgesia i.e., pressure pain sensitivity and conditioned pain modulation. Secondary outcome measurements included pain relief and reduced disability level.Local pressure pain sensitivity at baseline and during conditioned pain modulation decreased significantly more following acupuncture compared with relaxation (time × group interactions: p0.001), both in the neck and at a site distinct from the painful region. When comparing the effects of acupuncture versus relaxation, no differences were observed on conditioned pain modulation, temporal summation of pressure pain, neck disability or symptom severity (all p-values0.05).It was shown that one session of acupuncture treatment results in acute improvements in pressure pain sensitivity in the neck and calf of patients with chronic WAD. Acupuncture had no effect on conditioned pain modulation or temporal summation of pressure pain. Both acupuncture and relaxation appear to be well-tolerated treatments for people with chronic WAD. These findings suggest that acupuncture treatment activates endogenous analgesia in patients with chronic WAD.

Summary Purpose: To compare the pharmacokinetics of carisbamate (RWJ-333369) in healthy Japanese and Western adults, and to comparatively assess carisbamate safety and tolerability between the two populations. Methods: An open-label study was conducted in 24 Japanese and 24 Caucasian healthy subjects. Subjects received a single oral dose of 250 mg carisbamate on day 1 followed by a 3-day washout period; twice-daily dosing of 250 mg carisbamate on days 5–8; subsequently, 500 mg on days 9–12 and a single dose of 500 mg on day 13. Plasma samples were collected for a pharmacokinetic analysis on days 1, 8, and 13. Plasma and urine samples were analyzed for carisbamate and its urinary metabolites by liquid-chromatography-mass-spectrometry. Results: Following a single dose, carisbamate Cmax and area under the curve (AUC) geometric mean ratios were 16.4% and 28.8% higher in Japanese than in Caucasians, respectively; these differences were statistically significant and their 90% confidence intervals (CIs) fell outside of the 80–125% limits, which are considered not to be of clinical significance. With dose–body weight normalization, Cmax and AUC were similar in Japanese and Caucasian subjects and the 90% CIs were within the 80–125% boundaries. Carisbamate was well tolerated, and its mean oral clearance and half-life were similar in both groups, ranging from 35.1–41.4 ml/h/kg and 11.5–12.8 h. Discussion: Carisbamate plasma exposure (AUC) and Cmax in Japanese subjects is ∼20–25% higher than in Caucasians due to a higher mg/kg dose. After body weight normalization, carisbamate pharmacokinetics was similar between Japanese and Caucasian subjects following single and multiple dosing, and showed the same dose proportionality.

The levels of TMC207 (R207910) that can be reached in mouse organs and the sputa of treated patients easily exceed the MIC of the compound and can therefore interfere with in vitro bacterial titrations. We studied the usefulness of protein-enriched media for the prevention of such drug carryover effects. The average MIC of Mycobacterium tuberculosis was determined on three different media: unsupplemented 7H11 agar (MIC = 0.03 μg/ml), 7H11 agar supplemented with 5% bovine serum albumin (BSA; MIC = 1 μg/ml), and Lowenstein-Jensen medium (MIC = 14.33 μg/ml). In a second stage of the study, the maximal noninhibitory concentrations (MNICs) of TMC207 were determined by adding TMC207 to the bacterial inoculum rather than to the culture medium. These MNICs were 0.97 μg/ml for 7H11 agar, 32.33 μg/ml for 7H11 agar with 5% BSA, and 96.33 μg/ml for Lowenstein-Jensen medium. Both protein-enriched media were able to prevent drug carryover effects, but the use of 7H11 medium supplemented with 5% BSA is preferred for practical reasons.

RWJ-333369 (1,2-ethanediol, [1-2-chlorophenyl]-, 2-carbamate, [S]-; CAS Registry Number 194085-75-1) is a novel neuromodulator in clinical development for the treatment of epilepsy. To study the disposition of RWJ-333369, eight healthy male subjects received a single oral dose of 500 mg of (14)C-RWJ-333369. Urine, feces, and plasma were collected for analysis for up to 1 week after dosing. Radioactivity was mainly excreted in urine (93.8 +/- 6.6%) and much less in feces (2.5 +/- 1.6%). RWJ-333369 was extensively metabolized in humans, since only low amounts of parent drug were excreted in urine (1.7% on average) and feces (trace amounts). The major biotransformation pathways were direct O-glucuronidation (44% of the dose), and hydrolysis of the carbamate ester followed by oxidation to 2-chloromandelic acid, which was subsequently metabolized in parallel to 2-chlorophenyl glycine and 2-chlorobenzoic acid (mean percentage of the dose for the three acids together was 36%). Other routes were chiral inversion followed by O-glucuronidation (11%), and aromatic hydroxylation in combination with sulfate conjugation (5%). In plasma, unchanged drug accounted for 76.5% of the total radioactivity, with the R-enantiomer and the O-glucuronide of the parent drug as the only measurable plasma metabolites. With the use of very sensitive liquid chromatography-tandem mass spectrometry techniques, only traces of aromatic (pre)mercapturic acid conjugates were detected in urine (each0.3% of the dose), suggesting a low potential for reactive metabolite formation. In conclusion, the disposition of RWJ-333369 in humans is characterized by virtually complete absorption, extensive metabolism, and unchanged drug as the only significant circulating species.

Background Many patients with chronic pain, including those with chronic whiplash-associated disorders (WAD), show features of central sensitization. Randomized trials examining whether treatments are able to influence the process of central sensitization in patients with chronic WAD are emerging. Therefore, the present study aimed at examining whether acupuncture results in activation of endogenous analgesia and relief in symptoms in patients with chronic WAD. Methods In this randomized crossover pilot trial with blinded assessors, each patient (n = 39) received two treatment sessions of identical duration, with acupuncture and relaxation therapy randomly crossed over in visit 2. Primary outcome measurement included immediate activation of endogenous analgesia i. e., pressure pain sensitivity and conditioned pain modulation. Secondary outcome measurements included pain relief and reduced disability level. Results Local pressure pain sensitivity at baseline and during conditioned pain modulation decreased significantly more following acupuncture compared with relaxation (time x group interactions: p 0.05). Conclusion It was shown that one session of acupuncture treatment results in acute improvements in pressure pain sensitivity in the neck and calf of patients with chronic WAD. Acupuncture had no effect on conditioned pain modulation or temporal summation of pressure pain. Both acupuncture and relaxation appear to be well-tolerated treatments for people with chronic WAD. These findings suggest that acupuncture treatment activates endogenous analgesia in patients with chronic WAD.

R115777 is a selective, nonpeptidomimetic inhibitor of farnesyltransferase (FTase), an enzyme responsible for the post-translational modification of several proteins, including Ras. Given the high frequency of K-Ras mutations in malignancies commonly treated with irinotecan, the broad preclinical antiproliferative activity of R115777 and its largely non-overlapping toxicity profile with irinotecan, this phase I study of the combination of R115777 and irinotecan in patients with advanced cancer was undertaken. Enrolled onto the study were 14 patients (eight male, six female; median age 63 years, range 48–72 years). Five patients had an ECOG performance status (PS) of 0, eight patients PS 1, and one patient PS 2. The patients were treated with R115777 orally twice daily for 28 days and irinotecan 100 mg/m2 as an intravenous infusion on days 1, 8, 15, and 22 of each 42-day cycle. Seven patients received R115777 100 mg twice daily and seven received R115777 200 mg twice daily. Dose-limiting toxicity (DLT) was experienced by one of seven patients treated with R115777 100 mg (grade 3 fatigue), and two of seven patients treated with R115777 200 mg (grade 3 diarrhea, grade 4 neutropenia lasting >5 days). The maximum tolerated dose (MTD) was R115777 100 mg twice daily and irinotecan 100 mg/m2 weekly. Non-DLTs were primarily rash, fatigue, diarrhea, and neutropenia. R115777 demonstrated linear pharmacokinetics without interaction with irinotecan and achieved serum levels required for antitumor activity in vitro. Serum levels of R115777 exceeded those necessary for FTase inhibition in vitro without evidence of interaction with irinotecan. However, the MTD of R115777 in this study was lower than that obtained with an alternate schedule. Thus, further development of this schedule is not recommended.

In this publication, single and repeated dose experiments in rats, mice, rabbits and dogs are reported to assess the pharmacokinetics of galantamine (CAS-1953-04-4), a tertiary alkaloid with reversible cholinesterase inhibiting and nicotinic receptor modulatory properties developed for the treatment of Alzheimer’s disease in humans. Rats received single i.v. and single and repeated oral administrations of various doses, up to 160 mg/kg/day. In mice, only repeated oral administration of galantamine was investigated, up to 40 mg/ kg/day. Galantamine single and repeated oral doses up to 32 mg/kg/day were administered to female pregnant rabbits. Beagle dogs received single i.v. and single and repeated oral administrations of doses up to 8 mg/kg/day. Generally, oral absorption was rapid, with maximal plasma levels reached within 2 h in all species. Absolute oral bioavailability of a gavage dose was high in rat (77 %) and dog (78 %). In mice and rats, the bioavailability of galantamine administered via the food was lower than of galantamine administered by gavage. Elimination half-life of galantamine was relatively large in rat and dog and smaller in mouse and rabbit. In general, galantamine displayed dose-proportional to somewhat more than dose-proportional kinetics. In rats, plasma levels were lower in females than in males, whereas in mice, females showed higher levels than males. No gender differences were observed in dogs. No relevant differences in exposure to galantamine were found in rats and dogs upon oral administration of galantamine obtained as a natural extract or from chemical synthesis. The exposure to the active metabolite norgalantamine in plasma of the different animal species was low, except in the dog where the steady-state norgalantamine exposure was approximately 75 % of galantamine exposure. Galantamine plasma levels after single and repeated administration of 10 mg/kg/day in all species investigated except female rat and rabbit were much higher than mean therapeutic plasma levels of galantamine obtained in humans. The pharmacokinetic profile of galantamine after repeated oral administration in rats was most similar to the profile obtained after repeated administration of 12 mg b.i.d. in man.

Purpose: R115777 is a selective nonpeptidomimetic inhibitor of farnesyltransferase (FTase), one of several enzymes responsible for posttranslational modification that is required for the function of p21ras and other proteins. Given that RAS mutations are nearly universal in pancreatic cancer and R115777 demonstrated preclinical activity against pancreatic cell lines and xenografts, this phase II study was undertaken to determine its clinical activity and effect on target proteins in patients with measurable metastatic pancreatic adenocarcinoma. Patients and Methods: Twenty patients who had not received prior therapy for metastatic disease were treated with 300 mg of R115777 orally every 12 hours for 21 of 28 days. Inhibition of FTase activity in peripheral-blood mononuclear cells was measured using a lamin B C-terminus peptide as substrate. Western blot analysis was performed to monitor farnesylation status of the chaperone protein HDJ-2. Results: No objective responses were seen. Median time to progression was 4.9 weeks, and median survival time was 19.7 weeks. The estimated 6-month survival rate was 25%, with no patients progression-free at 6 months. Grade 3/4 toxicities were liver enzyme elevation, anemia, neutropenia, thrombocytopenia, fatigue, nausea/vomiting, rash, and anorexia. FTase activity (mean ± SD) decreased by 49.8% ± 9.8% 4 hours after treatment on day 1 and 36.1% ± 24.8% before treatment on day 15. HDJ-2 farnesylation (mean ± SD) decreased by 33.4% ± 19.8% on day 15. Conclusion: Although treatment with R115777 resulted in partial inhibition of FTase activity in mononuclear cells, it did not exhibit single-agent antitumor activity in patients with previously untreated metastatic pancreatic cancer.

To explore the steady-state pharmacokinetic profile after coadministration of galantamine and risperidone, an open-label, randomized, single-center, two-way crossover drug-drug interaction study was conducted in 16 healthy elderly subjects, ages 60 years and older. The results showed that risperidone, when administered with galantamine, did not change the bioavailability of galantamine at steady state. In addition, systemic exposure of risperidone active moiety (risperidone plus 9-hydroxyrisperidone), the most clinically relevant component of risperidone treatment, was not affected by galantamine coadministration, while systemic exposure was increased by approximately 10% for risperidone and decreased by about 10% for 9-hydroxyrisperidone (active metabolite of risperidone). Galantamine and risperidone were both safe and well tolerated administered either alone or together. Thus, no dose adjustment for either risperidone or galantamine is necessary when these two drugs are administered together in the dose range evaluated.

The aim of this study was to compare the pharmacokinetics of galantamine in healthy Japanese and Caucasian subjects and assess the safety and tolerability of galantamine in both ethnic groups. Parallel groups of healthy Japanese (n = 13; 6 males and 7 females)and Caucasian (n = 12; 6 males and 6 females) subjects matched for weight and age received single oral doses of galantamine 4 mg, or galantamine 8 mg, or placebo in a double-blind, three-way crossover trial according to a randomized dosing schedule. Concentrations of galantamine and norgalantamine were determined in plasma and urine samples taken up to 48 and 24 hours after dosing, respectively. Safety and tolerability were monitored throughout the trial by recording adverse events, laboratory tests, and cardiovascular parameters. The mean plasma concentration-time profiles of galantamine were very similar after single doses of galantamine (4 and 8 mg), and there was an approximate dose proportionality of galantamine pharmacokinetic parameters in both Caucasian and Japanese ethnic groups. The mean (+/- SD) pharmacokinetic parameters in the two ethnic groups did not show any clinically relevant differences. The ratios for the area under the plasma-concentration curve from time zero to infinity (AUC)0-infinity) in Japanese:Caucasian subjects with 4 and 8 mg doses were 103% (90% confidence interval [CII = 92-116) and 107% (90% CI = 94-121), respectively. Ratios for maximum plasma concentration (Cmax) values were 107% (90% CI= 90-127) and 108% (90% CI= 95-123), respectively. These ratios and associated 90% CIs were within the 80% to 125% range limit of bioequivalence. Analysis of variance (ANOVA) showed that these ratio values demonstrated no statistically significant difference between the two ethnic groups. There was no overt difference in the adverse event profile in Japanese subjects compared with Caucasian subjects. There were no serious adverse events, and no subjects discontinued from the study because of adverse events. No consistent or clinically relevant pattern of blood chemistry, hematology, or cardiovascular changes was seen. These results suggest that the pharmacokinetic profiles of galantamine after single-dose administration are not statistically significantly different between Caucasian and Japanese groups. Galantamine was well tolerated. The safety and tolerability of galantamine were very similar in the two ethnic groups.

Galantamine is a competitive acetylcholine esterase inhibitor with a beneficial therapeutic effect in patients with Alzheimer's disease. The metabolism and excretion of orally administered (3)H-labeled galantamine was investigated in rats and dogs at a dose of 2.5 mg base-Eq/kg body weight and in humans at a dose of 4 mg base-Eq. Both poor and extensive metabolizers of CYP2D6 were included in the human study. Urine, feces, and plasma samples were collected for up to 96 h (rats) or 168 h (dogs and humans) after dosing. The radioactivity of the samples and the concentrations of galantamine and its major metabolites were analyzed. In all species, galantamine and its metabolites were predominantly excreted in the urine (from 60% in male rats to 93% in humans). Excretion of radioactivity was rapid and nearly complete at 96 h after dosing in all species. Major metabolic pathways were glucuronidation, O-demethylation, N-demethylation, N-oxidation, and epimerization. All metabolic pathways observed in humans occurred in at least one animal species. In extensive metabolizers for CYP2D6, urinary metabolites resulting from O-demethylation represented 33.2% of the dose compared with 5.2% in poor metabolizers, which showed correspondingly higher urinary excretion of unchanged galantamine and its N-oxide. The glucuronide of O-desmethyl-galantamine represented up to 19% of the plasma radioactivity in extensive metabolizers but could not be detected in poor metabolizers. Nonvolatile radioactivity and unchanged galantamine plasma kinetics were similar for poor and extensive metabolizers. Genetic polymorphism in the expression of CYP2D6 is not expected to affect the pharmacodynamics of galantamine.

Eight N-(4-hydroxycarbamoylbenzyl)-1,2,4,9-tetrahydro-3-thia-9-azafluorenes were efficiently prepared as sulfur analogues of Tubastatin A and thus evaluated as new HDAC6 inhibitors. All compounds exhibited potency against HDAC6, and four of them were active in the nanomolar range (IC(50) = 1.9-22 nM). Further analysis revealed that the sulfone derivatives (designated as Tubathians) are superior to their non-oxidized sulfide analogues, and the two most active sulfones showed good to excellent HDAC6 selectivity compared to all other HDAC isoform classes.

William B Smith,1 Erik Mannaert,2 Tom Verhaeghe,2 René Kerstens,3 Lieve Vandeplassche,3 Vera Van de Velde41Volunteer Research Group and New Orleans Center for Clinical Research, The University of Tennessee Medical Center, Knoxville, TN, USA; 2Janssen Research and Development, a division of Janssen Pharmaceutica NV, Beerse, Belgium; 3Shire-Movetis NV, Turnhout, Belgium; 4Independent Consultant Clinical Pharmacokinetics, Princeton, NJ, USAObjective: To evaluate the pharmacokinetics of prucalopride in individuals with renal impairment (RI).Methods: This open-label Phase I study (ClinicalTrials.gov identifier: NCT01674192) enrolled men and women aged 18–75 years who were classified by renal function: normal renal function (creatinine clearance ≥ 80 mL/min/1.73 m2), mild RI (50–79 mL/min/1.73 m2), moderate RI (25–49 mL/min/1.73 m2), and severe RI (≤24 mL/min/1.73 m2). All received a single oral dose of prucalopride 2 mg.Results: Thirty-four individuals (normal renal function: 10; mild RI: 8; moderate RI: 7; severe RI: 9) received prucalopride. In all groups, maximum plasma concentration was reached within 2–4 hours. There was no significant difference in exposure (area under the plasma concentration–time curve from time zero to infinity) between participants with mild RI and those with normal renal function. However, area under the plasma concentration–time curve from time zero to infinity values were 1.5- and 2.3-fold higher (P = 0.002 and P < 0.001) in patients with moderate RI and severe RI, respectively, than in those with normal renal function. The proportion of total body clearance accounted for by renal clearance was significantly reduced in those with RI.Conclusion: Clinically meaningful reductions in renal clearance were seen in participants with severe RI, which supports a decrease from the standard dose of prucalopride 2 mg daily to 1 mg daily in these individuals.Keywords: renal impairment, pharmacokinetics, prucalopride, safety