MK-6194, an interleukin-2 mutein designed to selectively activate regulatory T cells (Tregs), was evaluated for safety, pharmacokinetics (PK), immunogenicity, and pharmacodynamics in healthy participants. In a single ascending dose trial (N = 56), participants received subcutaneous MK-6194 or placebo (3:1 ratio) across dose levels ranging from 1 to 10 mg. In a multiple ascending dose trial (N = 54), participants received subcutaneous MK-6194 or placebo (3:1 ratio) at dose levels ranging from 0.5 to 5 mg every 2 wk (total 3 doses) as well as 5 mg every 4 wk (total 2 doses). Baseline characteristics were comparable between trials, with participants mostly male with a mean age of 36 yr. There were no serious adverse events or dose-limiting toxicities. The most common adverse events were injection site erythema and eosinophil count elevations (with no indication of severe eosinophilia or eosinophilia-related organ damage). PK showed dose-proportionality and repeated doses of MK-6194 did not result in accumulation or time-dependent PK. Immunogenicity was low with no impact on PK or safety. Treg expansion as assessed by flow cytometry and Treg-specific demethylation region analysis was observed in a dose-dependent manner during both trials and expanded within about 8 d postdose up to about 5-fold and returned to baseline by 14 to 29 d postdose. Minimal impact was observed on other lymphocytes including total T lymphocyte and natural killer cell counts. These findings support the further development of MK-6194 as a potential treatment for autoimmune disorders.

Objective: To assess the antiviral activity, pharmacokinetics, and safety of MK-6186 in HIV-1 non-nucleoside reverse transcriptase inhibitor (NNRTI)-naïve, HIV-1-infected male participants. Design: Double-blind, randomized, two-panel study. Methods: In 2 sequential panels, 18 participants received MK-6186 (40 mg [Panel A] or 150 mg [Panel B]) or matching placebo once daily for 7 days. Plasma samples were collected for measurement of HIV-1 RNA levels and MK-6186 pharmacokinetics. Results: For the mean change from baseline in HIV-1 RNA (log10 copies/mL) at 24 h post Day 7 dose, the mean difference (90% confidence interval) between MK-6186 and placebo was -1.54 (-1.73, -1.34) in the 40-mg group and -1.28 (-1.81, -0.75) in the 150-mg group. One participant in the 150-mg group had viral rebound at 24 h after Day 6 dosing (Day 7 predose) associated with outgrowth of the V106A minority variant. Ultra-deep sequencing confirmed expansion of this predose minority variant from 0.26% to 63.67%. No outgrowth or rebound was seen in another participant in whom a V106A minority variant was also detected. MK-6186 was generally well tolerated. MK-6186 was rapidly absorbed with peak concentrations at 2 h followed by a biphasic decline. The effective t½ of MK-6186 was 43.9 to 48.7 h. Steady state was not achieved. Conclusions: Daily monotherapy with MK-6186 demonstrated robust antiviral activity with maximal antiviral activity at a dose of 40 mg. One participant in the 150-mg group exhibited viral rebound with outgrowth of the resistant V106A minority variant, demonstrating a risk of resistance development typical of NNRTIs. The reason for this outgrowth remains unclear as no outgrowth occurred in a participant in the 40-mg group in whom the V106A minority variant was also detected. MK-6186 may be an alternative next-generation NNRTI in combination therapy, in that combination antiretroviral therapy could prevent outgrowth of resistant minority variants.

Renal impairment (RI) is known to influence the pharmacokinetics of nonrenally eliminated drugs, although the mechanism and clinical impact is poorly understood. We assessed the impact of RI and single dose oral rifampin (RIF) on the pharmacokinetics of CYP3A, OATP1B, P‐gp, and BCRP substrates using a microdose cocktail and OATP1B endogenous biomarkers. RI alone had no impact on midazolam (MDZ), maximum plasma concentration (Cmax), and area under the curve (AUC), but a progressive increase in AUC with RI severity for dabigatran (DABI), and up to ~2‐fold higher AUC for pitavastatin (PTV), rosuvastatin (RSV), and atorvastatin (ATV) for all degrees of RI was observed. RIF did not impact MDZ, had a progressively smaller DABI drug‐drug interaction (DDI) with increasing RI severity, a similar 3.1‐fold to 4.4‐fold increase in PTV and RSV AUC in healthy volunteers and patients with RI, and a diminishing DDI with RI severity from 6.1‐fold to 4.7‐fold for ATV. Endogenous biomarkers of OATP1B (bilirubin, coproporphyrin I/III, and sulfated bile salts) were generally not impacted by RI, and RIF effects on these biomarkers in RI were comparable or larger than those in healthy volunteers. The lack of a trend with RI severity of PTV and several OATP1B biomarkers, suggests that mechanisms beyond RI directly impacting OATP1B activity could also be considered. The DABI, RSV, and ATV data suggest an impact of RI on intestinal P‐gp, and potentially BCRP activity. Therefore, DDI data from healthy volunteers may represent a worst‐case scenario for clinically derisking P‐gp and BCRP substrates in the setting of RI.

MK‐8507 is an investigational HIV‐1 nonnucleoside reverse transcriptase inhibitor being developed for the treatment of HIV‐1 infection. MK‐8507 contains 2 trifluoromethyl groups that may result in fluoride release through metabolism, but the extent of MK‐8507–related fluoride release in humans has yet to be determined. This double‐blind, placebo‐controlled, 2‐period, parallel‐group, multiple‐dose trial in healthy participants without HIV‐1 who were administered a fluoride‐restricted diet and once‐weekly doses of MK‐8507 aimed to estimate the relationship between MK‐8507 dose and fluoride exposure. A total of 15 adult male and 3 adult female (of non‐childbearing potential) participants were randomized to receive MK‐8507 200 mg (n = 6), MK‐8507 800 mg (n = 6), or placebo (n = 6). Change from baseline in mean daily fluoride excretion averaged over 7 days following the administration of MK‐8507 200 mg resulted in a net mean increase of 19.8 μmol (90% confidence interval, 12.2‐27.4) relative to placebo and did not exceed 57 μmol, a threshold related to the mean difference between the daily reference dose set by the US Environmental Protection Agency and the average dietary fluoride intake in the United States. However, daily urinary fluoride excretion exceeded the threshold following administration of 800 mg MK‐8507 (75.1 μmol [90% confidence interval, 67.5‐82.7]). Assuming a linear relationship between MK‐8507 dose and estimated mean daily fluoride released at steady‐state, data interpolation suggests that the US Environmental Protection Agency reference dose for fluoride would not be exceeded in most patients when administering MK‐8507 at doses currently under clinical investigation (≤400 mg once weekly).

Chronic overexposure to fluoride can have deleterious effects in the musculoskeletal system. Some fluorine-containing therapeutics, such as voriconazole, release fluoride through metabolism. Therefore, drug-related fluoride exposure should be assessed for novel therapeutics suspected of releasing fluoride through metabolism. Two trials were conducted to identify the optimal method of assessing drug-related fluoride exposure. In trial 1, designed to assess reproducibility of fluoride pharmacokinetics in urine and plasma, 14 participants were administered a fluoride-restricted diet and once-daily doses of sodium fluoride (2.2 mg [1 mg of fluoride] on days 1 and 2; and 13.2 mg of sodium fluoride [6 mg of fluoride] on days 3 and 4). In trial 2, designed to confirm the selected method for fluoride detection, 12 participants were administered a fluoride-restricted diet and randomized to receive voriconazole (400 mg twice, 12 hours apart, on day 1 [131 mg/d of fluoride maximum], then 3 doses of 200 mg every 12 hours [65.3 mg/d of fluoride maximum]) or placebo. Plasma fluoride concentrations and urinary fluoride excretion were assessed in each trial. Assessment of plasma fluoride concentrations in trial 1 was limited by 301 of 854 samples (35.2%) below the lower limit of quantitation. Urine fluoride excretion was readily measured and demonstrated a decrease from baseline during the fluoride-restricted diet phase, as well as dose-proportional increases with fluoride administration. In trial 2, increases in urine fluoride were successfully observed in participants administered voriconazole. In conclusion, fluoride exposure was optimally assessed by urinary fluoride excretion in conjunction with strict dietary fluoride restrictions, as measurements were consistent and reproducible.

A new once‐daily formulation of raltegravir, an integrase strand transfer inhibitor indicated in combination with other antiretroviral drugs for the treatment of human immunodeficiency virus–1 infection, is under development. Single‐dose and steady‐state pharmacokinetics of 1200 mg for 2 formulations of raltegravir were characterized in 2 open‐label phase 1 studies in healthy male and female subjects aged 18 to 55 years. The new raltegravir 600‐mg formulation had a higher relative bioavailability compared with the 400‐mg tablets. Once absorbed, both 3 × 400‐mg and 2 × 600‐mg dosage forms of raltegravir exhibited similar systemic pharmacokinetics; in dictating bioavailability, differences were from increased absorption that was the result of improved in vivo disintegration/dissolution. Food had a smaller effect on the pharmacokinetics of raltegravir when given as 2 × 600‐mg formulation (42% vs 73% decrease in AUC0–last). Steady state was generally reached in 2 days, with little to no accumulation with multiple‐dose administration. Raltegravir 1200 mg was found to exhibit pharmacokinetic properties amenable for once‐daily dosing and was generally well tolerated in healthy subjects after single and multiple doses. The new formulation improved the bioavailability of this Biopharmaceutics Classification System class II compound.

A novel modeling approach together with a use of group sequential study design for a complicated triple fixed-dose combination was attempted. Probability of success (POS) was used for determining a weighted average power, where weight was based on available information such as data from previous pilot studies or literature. A simulation study was conducted that resulted in the development of the necessary sample size for the studies in addition to identifying a decision algorithm that was prospectively defined in the protocols. Prospective inclusion of decision algorithms in the respective protocols facilitated a decision analytic approach to continuance or discontinuance of the product concept. Whereas the data suggested going to stage 2 was appropriate, the overall POS of meeting the equivalence requirements upon completion of the study were very low, leading to termination of the selected formulation concepts. The use of such novel designs for bioequivalence assessment can be applied for staged investments, particularly when there is uncertainty in formulation POS or when the pilot-scale pharmacokinetic studies are not likely to predict the final-scale pivotal studies.

OBJECTIVES:A new improved mometasone furoate (Elocon™) cream with an emulsification system that produces a stable emulsion has been developed. In order to register the product in various markets, it was essential to ensure the cream was topically well tolerated and that it was bioequivalent to the reference product.METHODS:Phase I clinical studies were performed to assess the local safety and tolerability upon multiple dosing of this new cream as well as to assess the single-dose bioequivalence relative to the marketed product. Bioequivalence was assessed using a vasoconstrictive assay (VCA) after a dose-duration pilot study was completed with the marketed Elocon cream.KEY FINDINGS:The new mometasone cream and its vehicle were nonirritating in healthy subjects during 21-day patch application (MCII <0.025). The positive control was moderately irritating in the same study. The pivotal VCA study enrolled 162 subjects with 105 detectors included in the analysis of bioequivalence. In the 105 detectors, the ratio (×100%) of AUEC values at ED50 for test vs. standard (90% CI) was 112.91% (105.55, 120.87), within the bioequivalence criteria of (80, 125).CONCLUSIONS:These studies supported the registration of reformulated mometasone cream in various markets.

Raltegravir is a human immunodeficiency virus (HIV)-1 integrase strand transfer inhibitor currently marketed at a dose of 400 mg twice-daily (b.i.d.). Raltegravir 1200 mg once-daily (q.d.) (investigational q.d. formulation of 2 × 600 mg tablets; q.d. RAL) was found to be generally well tolerated and non-inferior to the marketed 400 mg b.i.d. dose at 48 weeks in a phase 3 trial. Since raltegravir is eliminated mainly by metabolism via a uridine diphosphate glucuronosyltransferase (UGT) 1A1-mediated glucuronidation pathway, co-administration of UGT1A1 inhibitors may increase the plasma levels of q.d. RAL. To assess this potential, the drug interaction of 1200 mg raltegravir using atazanavir, a known UGT1A1 inhibitor, was studied. An open-label, randomized, 2-period, fixed-sequence phase 1 study was performed in adult healthy male and female (non-childbearing potential) subjects ≥ 19 and ≤ 55 years of age, with a body mass index (BMI) ≥ 18.5 and ≤ 32.0 kg/m2 . Subjects (n = 14) received a single oral dose of 1200 mg raltegravir in period 1. After a washout period of at least 7 days, the subjects received oral doses of 400 mg atazanavir q.d. for 9 consecutive days, with a single oral dose of 1200 mg raltegravir co-administered on day 7 of period 2. Serial blood samples were collected for 72 h following raltegravir dosing and analysed using a validated bioanalytical method to quantify raltegravir plasma concentrations. Co-administration with atazanavir yielded GMRs (90% CIs) for raltegravir AUC0-∞ , Cmax and C24 of 1.67 (1.34, 2.10), 1.16 (1.01, 1.33) and 1.26 (1.08, 1.46), respectively. There was no effect of raltegravir on serum total bilirubin. In contrast, atazanavir increased the mean bilirubin by up to 200%, an effect that was preserved in the atazanavir/raltegravir treatment group. Administration of single q.d. RAL alone and co-administered with multiple oral doses of atazanavir were generally well tolerated in healthy subjects. The results show that atazanavir increased the PK exposure of raltegravir; therefore, co-administration of atazanavir with raltegravir q.d. is not recommended. Copyright © 2016 John Wiley & Sons, Ltd.

Raltegravir is a human immunodeficiency virus (HIV)-1 integrase strand transfer inhibitor currently marketed at a dose of 400 mg twice daily (BID). Raltegravir for once daily regimen (QD) at a dose of 1200 mg (2 x 600 mg) is under development and offers a new treatment option for HIV-1 infected treatment-naive subjects. Since raltegravir is eliminated mainly by metabolism via an UDP-glucuronosyltransferase (UGT) 1 A1-mediated glucuronidation pathway, co-administration of UGT1A1 inducers may alter plasma levels of raltegravir. Efavirenz, an UGT1A1 inducer, was used to assess the impact of altered UGT activity on a 1200 mg QD dose of raltegravir. An open label, randomized, 2-period fixed-sequence Phase 1 study was performed in adult healthy male and female subjects (non-childbearing potential) ≥ 19 and ≤55 years of age, with a body mass index (BMI) ≥ 18.5 and ≤32.0 kg/m2 . Subjects (n = 21) received a single oral dose of 1200 mg raltegravir at bedtime on an empty stomach on Day 1 in Period 1. After a washout period of at least 7 days, subjects received oral doses of 600 mg efavirenz QD at bedtime for 14 consecutive days in Period 2. Subjects received a single oral dose of 1200 mg raltegravir co-administered with 600 mg efavirenz on Day 12 of Period 2. Pharmacokinetic (PK) samples were collected for 72 hours following raltegravir dosing and analyzed using a validated bioanalytical method to quantify raltegravir plasma concentrations. PK parameters were estimated using non-compartmental analysis. Administration of single 1200 mg oral doses of raltegravir alone and co-administered with multiple oral doses of efavirenz were generally well tolerated in healthy subjects. Co-administration with efavirenz yielded geometric mean ratios (GMRs) and their associated 90% confidence intervals (90% CIs) for raltegravir AUC0-∞, Cmax , and C24 of 0.86 (0.73, 1.01), 0.91 (0.70, 1.17), and 0.94 (0.76, 1.17), respectively. The results show that efavirenz modestly reduced the exposure of raltegravir. The reduction in raltegravir exposure is not considered clinically meaningful. Copyright © 2016 John Wiley & Sons, Ltd.

Objectives Raltegravir is a human immunodeficiency virus (HIV)-1 integrase strand transfer inhibitor currently marketed at a dose of 400 mg twice daily (BID). Raltegravir for once-daily regimen (QD) at a dose of 1200 mg is under development. The effect of calcium carbonate and magnesium/aluminium hydroxide antacids on the pharmacokinetics of a 1200 mg dose of raltegravir was assessed in this study.Methods An open-label, four-period, four-treatment, fixed-sequence study in 20 HIV-infected patients was performed. Patients needed to be on raltegravir as part of a stable treatment regimen for HIV, and upon entry into the trial received 5 days of 1200 mg raltegravir as pretreatment, before they entered the four-period study: 1200 mg of raltegravir alone (period 1), calcium carbonate antacid as TUMS (R) Ultra Strength (US) 1000 and 1200 mg raltegravir given concomitantly (Period 2), magnesium/aluminium hydroxide antacid as 20 ml MAALOX (R) Maximum Strength substitute MS given 12 h after administration of 1200 mg raltegravir (period 3), and calcium carbonate antacid as TUMS (R) US 1000 given 12 h after administration of 1200 mg raltegravir (period 4). Patients received their dose of 1200 mg QD raltegravir during the intervals between periods to re-establish steady state. AUC(0-24), C-24, C-max and T-max were calculated from the individual plasma concentrations of 1200 mg QD raltegravir after administration alone or with a calcium carbonate antacid or with a staggered dose of a calcium carbonate antacid or magnesium/aluminium hydroxide antacid. Adverse events, in addition to laboratory safety tests (haematology, serum chemistry and urinalysis), 12-lead electrocardiograms and vital signs were assessed.Key findings All treatments were well tolerated in the study. Metal-cation antacids variably affected the pharmacokinetics of 1200 mg QD raltegravir. When calcium carbonate antacid was given with 1200 mg raltegravir concomitantly, the geometric mean ratio (GMR) and its associated 90% confidence interval (90% CI) for AUC(0-24), C-max and C-24 h were 0.28 (0.24, 0.32), 0.26 (0.21, 0.32) and 0.52 (0.45, 0.61), respectively. When calcium carbonate antacid and magnesium/aluminium hydroxide were given 12 h after raltegravir 1200 mg QD dosing, the GMR (90% CI) values for AUC(0-24) and C-max were 0.90 (0.80, 1.03), 0.98 (0.81, 1.17), and 0.86 (0.73, 1.03), 0.86 (0.65, 1.15), respectively. However, significant reduction in the trough concentrations of raltegravir was observed: C-24 h 0.43 (0.36, 0.51) in the presence of calcium carbonate antacids and 0.42 (0.34, 0.52) in presence of magnesium/aluminium hydroxide, respectively.Conclusions Overall, the use of metal-cation antacids with 1200 mg QD raltegravir is not recommended.

Background Raltegravir is an integrase strand transfer inhibitor indicated in combination with other anti-retroviral medicinal products for the treatment of HIV-1 infection, given twice daily. Although a BCS class II compound, raltegravir exhibits low colonic absorption, thus making development of modified release formulations challenging. It was hypothesized that a gastroretentive (GR) formulation would increase trough (C 24 h ) concentrations of raltegravir, hence being amenable to a once-daily (QD) regimen. Methods Iterative prototype GR formulations were developed in monolithic, bilayer, and trilayer tablet designs. Four phase I studies in healthy subjects were conducted to provide proof of formulation concept. Results Raltegravir C 24 h was increased by a GR formulation with scintigraphy data supporting gastric retention. Single-dose exposures from a trilayer tablet administered in the morning with a high-fat meal resulted in acceptable C 24 h values. However, C 24 h values for evening dosing with a high-fat meal did not meet the success criteria for QD administration. Raltegravir C 24 h and area under the curve (AUC) values after AM dosing with a low-fat meal were significantly lower than after dosing with a moderate-fat meal. Skipping, delaying, or giving a low-fat, low-calorie lunch after dosing with a high-calorie breakfast also resulted in an unacceptable decline in C 24 h values. The requirements for consistent product performance under varying conditions of diet, timing of dosing, and dose were not favorable when given as GR tablets. Conclusions The findings from these studies offer valuable insights into modifying the absorption of candidate drugs with limiting colonic permeability and solubility characteristics and the interplay between meal, dose timing, and GR formulation performance.

Background. ISENTRESS (raltegravir, RAL) is licensed for 400 mg b.i.d. use. An investigational 1200 mg q.d. regimen for reformulated raltegravir (re-RAL) is under clinical development. This study assessed the safety and pharmacokinetics (PK) of a higher dose of re-RAL. Methods. A double-blind, multiple-dose, randomized, fully domiciled study assessed the safety and PK of 1800 mg dose of re-RAL tablets (n = 18) or matching placebo (n = 6), given q.d. for 28 days in healthy subjects (18 to 55 years). Results. There were no deaths and no serious adverse events. There were no clinically significant findings for vital signs or ECG data. A total of 23 subjects (95.8%) reported an adverse event (AE) that was related to the study drug [17 subjects (94.4%) after 1800 mg re-RAL and 6 subjects (100%) after matched placebo]. Two subjects withdrew their consent at Day 28 for personal reasons. No subjects discontinued the study due to AEs or changes in laboratory safety. Most common adverse events, reported in ≥6 subjects, included headache, myalgia, and abdominal pain. No subjects experienced ALT >5x upper limit of normal (ULN) in this study. One subject experienced ALT >3x ULN on Day 9 and another subject experienced ALT >2x ULN on Day 13, after 1800 mg re-RAL administration. No associated clinically significant symptoms were seen and the elevations stabilized or returned to normal without interruption of study therapy. Three subjects experienced CPK elevations which were rated severe in intensity and were considered related to the study drug. In two subjects, the first CPK elevations were detected at the post study visit held 2-weeks following completion of the dosing. While one subject showed asymptomatic increase in CPK level, CPK elevations in two subjects were symptomatic. RAL PK was comparable on Days 14 and 28. On Day 28, the mean values of RAL Cmax, C24hr, and AUC0-24hr were 29 μM, 88.5 nM, 74.5 hr. μM, respectively, as compared with 20.6 μM, 81.1 nM, and 59.5 hr.μM, respectively, at the 1200 mg dose being evaluated in Phase 3. There were no apparent relationship between PK and observed elevations in ALT or CPK. Conclusion. Administration of 1800 mg q.d. doses of re-RAL was safe and well tolerated. Data from this study, in combination with other recently completed Phase I studies, support the continued development of the q.d. dosing regimen. Disclosures. R. Krishna, Merck and Co.: Employee, Salary M. Rizk, Merck and Co., Inc.: Employee, Salary V. Schulz, Merck and Co., Inc.: Employee, Salary J. Bruggencate-Broeders, Merck and Co.: Employee, Salary R. Liu, Merck and Co: Employee, Salary P. Larson, Merck and Co.: Employee, Salary K. Abou-Farha, Merck and Co., Inc.: Investigator, Investigator for Merck Study

Two open‐label, parallel‐group studies evaluated the influence of renal and hepatic insufficiency on the pharmacokinetics of a single‐dose anacetrapib 100 mg. Eligible participants included adult men and women with moderate hepatic impairment (assessed by Child–Pugh criteria) or severe renal impairment (CrCl <30 mL/min/1.73 m 2 ). In both studies, patients were matched (race, age, sex, BMI) with healthy control subjects. Twenty‐four subjects were randomized in each study (12 with either moderate hepatic or severe renal impairment and 12 matched healthy controls). In the hepatic insufficiency study, the geometric mean ratio (GMR; mean value for the group with moderate hepatic insufficiency/mean value for the healthy controls) and 90% CIs for the area under the concentration–time curve from time zero to infinity (AUC 0–∞ ) and the maximum concentration of drug in plasma (C max ) were 1.16 (0.84, 1.60) and 1.02 (0.71, 1.49), respectively. In the renal insufficiency study, the GMRs (mean value for the group with severe renal insufficiency/mean value for the healthy controls) and 90% CIs for AUC 0–∞ and C max were 1.14 (0.80, 1.63) and 1.31 (0.93, 1.83), respectively. Anacetrapib was generally well tolerated and there was no clinically meaningful effect of moderate hepatic or severe renal insufficiency on the pharmacokinetics of anacetrapib.

Anacetrapib is a cholesteryl ester transfer protein inhibitor in Phase III development. This double-blind, double-dummy, randomized, placebo- and active-comparator-controlled, 4-period, balanced crossover study evaluated the effects of anacetrapib (100mg and 800mg) on QTcF interval in healthy subjects. QTcF measurements were made up to 24h following administration of single doses of anacetrapib 100 or 800mg, moxifloxacin 400mg, or placebo in the fed state. The primary hypothesis was supported if the 90% CI for the least squares (LS) mean differences between anacetrapib 800mg and placebo in QTcF interval change from baseline were entirely <10 msec at every post-dose time point (1, 2, 2.5, 3, 4, 5, 6, 8, 12, and 24h). The upper bounds of the 90% CIs for LS mean differences from placebo in changes from baseline in QTcF intervals for anacetrapib 100 and 800mg were <5 msec at every time point. In conclusion, single doses of anacetrapib 100 and 800mg do not prolong the QTcF interval to a clinically meaningful degree relative to placebo and are generally well tolerated in healthy subjects.

AIMS:Sitagliptin is a selective inhibitor of dipeptidyl peptidase-4 (DPP-4) used to treat type 2 diabetes. The present aim was to evaluate pharmacokinetic (PK), pharmacodynamic (PD) and safety characteristics of sitagliptin following single doses in healthy, young Japanese males.METHODS:In this alternating two-panel, randomized, controlled double-blind study, six healthy Japanese male subjects (aged 20-46 years) in each panel received single oral doses of 5-400mg sitagliptin and two received placebo. Plasma and urine drug concentrations were measured from 0-48h post dose and plasma DPP-4 inhibition from 0-24h post dose. The results were compared with historical data from young, healthy non-Japanese males.RESULTS:Plasma concentrations of sitagliptin increased approximately in proportion to dose; maximum concentrations occurred 2-6h post-dose. The mean apparent terminal half-life for plasma sitagliptin was 9-14h, with the half-life slightly decreasing as the dose increased. The mean dose fraction excreted unchanged in the urine was 0.73-1.00. Ingestion of a traditional Japanese breakfast prior to dosing had only a minor effect on PK parameters. After correction for dilution and competition effects during assay, doses of sitagliptin ≥50mg resulted in weighted average DPP-4 inhibition from 0-24h post-dose >94% (without correction, >78%). No clinically meaningful differences in PK and DPP-4 inhibition parameters were found between Japanese and non-Japanese subjects. Sitagliptin was generally well tolerated and there were no serious adverse experiences or episodes of hypoglycaemia.CONCLUSIONS:The PK and PD findings from this study are consistent with once daily dosing of sitagliptin in Japanese patients with type 2 diabetes.

Sitagliptin is a dipeptidyl peptidase-IV (DPP-4) inhibitor used for the treatment of patients with type 2 diabetes mellitus. This randomized, placebo-controlled, 2-period, crossover study evaluated the effect of sitagliptin on the pharmacokinetics of 17 alpha-ethinyl estradiol (EE(2)) and norethindrone (NET) in healthy female subjects who were receiving oral contraceptives for > 3 months prior to enrollment. A total of 18 subjects with normal menstrual cycles received the oral contraceptive pill ORTHO-NOVUM (R) 7/7/7 on days 1 to 28 for 2 successive cycles, and on days 1 to 21 were randomly assigned to receive sitagliptin 200 mg/day (2 x 100 mg tablets) or placebo using a computer-generated allocation schedule. Blood samples for determination of plasma EE(2) and NET concentrations were collected predose and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 18, and 24 hours postdose on day 20 or 21 of each treatment period. The GMRs (90% confidence interval [CI]) for the AUC(0-24hr) of EE(2) and NET were 0.99 (0.93, 1.06) and 1.03 (0.97, 1.09), respectively, and for Cmax were 0.97 (0.86, 1.10) and 0.98 (0.89, 1.07), respectively. The coadministration of sitagliptin 200 mg/day with an oral contraceptive for 21 days did not lead to clinically meaningful alterations in the pharmacokinetics of EE(2) and NET.

These studies were designed to demonstrate that the alendronate (ALN) component of an ALN/vitamin D3 combination tablet was bioequivalent to the 70-mg ALN tablet and that the pharmacokinetic parameters of vitamin D3 were similar with or without ALN. These were open-label, randomized, 2-part, 2-period, crossover studies. In part I, participants received either a single combination tablet or ALN 70 mg. In part II, participants received either a single combination tablet or vitamin D3 alone. Results from part I showed that the geometric mean ratio (GMR) for total urinary excretion of ALN for both studies fell within the prespecified bioequivalence bounds. Results from part II showed that the pharmacokinetic profiles of vitamin D3 with or without ALN were also similar. The combination tablets are bioequivalent to the ALN 70-mg tablet with respect to ALN bioavailability. The bioavailability of vitamin D3 is similar in the combination tablets and when administered alone. No serious adverse experiences were reported.