Bioequivalence of rimegepant, a small molecule CGRP receptor antagonist, administered as an oral tablet, a sublingual orally disintegrating tablet, and a supralingual orally disintegrating tablet: two phase 1 randomized studies in healthy adults.

BACKGROUND: Rimegepant is an orally administered small molecule calcitonin gene-related peptide receptor antagonist indicated for the acute and preventive treatment of migraine. METHODS: Two single-center, phase 1, open-label, randomized bioequivalence studies were conducted in healthy adult non-smokers, aged 18-55 years. One study compared the rate and extent of absorption of the marketed formulation of rimegepant 75 mg orally disintegrating tablet (ODT) administered sublingually with rimegepant 75 mg oral tablet, an earlier development formulation; the second compared the rate and extent of absorption of 75 mg rimegepant ODT administered supralingually with rimegepant oral tablet. RESULTS: The ln-transformed geometric mean ratios for the area under the curve (AUC) from time 0 to the last available concentration time point (time t) (AUC0-t), AUC from time 0 to infinity (AUC0-inf), and maximum observed concentration (Cmax) of sublingual rimegepant ODT vs. rimegepant tablet were 97, 97, and 105%, respectively, and the 90% confidence intervals (CIs) were all within the predefined range (80-125%) for bioequivalence. The ln-transformed geometric mean ratios for the AUC0-t and AUC0-inf of supralingual rimegepant ODT vs. rimegepant tablet were 98%, the 90% CIs were within the predefined range (80-125%), and the geometric mean ratio for Cmax was 103% with the 95% upper confidence bound for the scaled average bioequivalence criterion of -0.0575 (within-participant coefficient of variation for the reference for Cmax > 30%) for bioequivalence. CONCLUSIONS: Rimegepant 75 mg ODT, administered sublingually or supralingually, and rimegepant 75 mg oral tablet were bioequivalent.

Relative bioavailability of ertugliflozin tablets containing the amorphous form versus tablets containing the cocrystal form.

OBJECTIVES: Ertugliflozin is a selective sodium-glucose cotransporter 2 inhibitor approved for the treatment of type 2 diabetes in adults. In its natural form, ertugliflozin exists as an amorphous solid with physicochemical properties that prevent commercial manufacture. The commercial product was developed as an immediate-release tablet, consisting of an ertugliflozin-L-pyroglutamic acid cocrystal of 1 : 1 molar stoichiometry as the active pharmaceutical ingredient. The ertugliflozin cocrystal may partially dissociate when exposed to high humidity for extended periods, leading to the formation of free amorphous ertugliflozin. Therefore, a study was conducted to estimate the relative bioavailability of ertugliflozin when administered in non-commercial formulated tablets containing the amorphous form vs. the cocrystal form. MATERIALS AND METHODS: In this phase 1, open-label, randomized, two-period, two-sequence, single-dose crossover study, 16 healthy subjects received 15 mg immediate-release ertugliflozin in its amorphous and cocrystal forms under fasted conditions, separated by a washout period of ≥ 7 days. Blood samples were collected post-dose for 72 hours to determine plasma ertugliflozin concentrations. RESULTS: Mean ertugliflozin plasma concentration-time profiles were nearly superimposable following administration of the amorphous and cocrystal forms. The 90% confidence intervals for the geometric mean ratios for AUCinf and Cmax were wholly contained within the pre-specified criteria for similarity (70 - 143%), as well as the acceptance range for bioequivalence (80 - 125%). Most adverse events were mild in intensity. CONCLUSION: Any dissociation of ertugliflozin to the amorphous form that occurs in tablets containing the cocrystal will not have any clinically meaningful impact on the oral bioavailability of ertugliflozin.

Effect of bosutinib on the absorption of dabigatran etexilate mesylate, a P-glycoprotein substrate, in healthy subjects.

PURPOSE: Bosutinib, a dual Src and Abl tyrosine kinase inhibitor for the treatment of chronic myeloid leukemia, demonstrated concentration-dependent inhibitory effects on P-glycoprotein (P-gp)-mediated digoxin efflux in vitro, suggesting that bosutinib may inhibit P-gp substrates. The effect of bosutinib on dabigatran etexilate mesylate (EM) absorption, a P-gp substrate, was evaluated. METHODS: In this open-label, randomized, single-dose, one-cohort, two-sequence, two-period crossover study, healthy, fed subjects received dabigatran EM (150 mg × 1 orally) alone or 1 h after receiving bosutinib tablets (100 mg × 5 orally). RESULTS: Dabigatran EM monotherapy and concurrent administration of dabigatran EM with bosutinib resulted in similar values for concentration time curves from time zero extrapolated to infinity (AUCinf), but slightly lower maximum plasma concentration (C max) values (AUCinf, 1182 and 1186 ng·h/mL, respectively; C max, 129.8 and 114.1 ng/mL). The time to maximum concentration for dabigatran was 2.99 and 3.99 h for combination therapy. The ratio of the adjusted geometric means (test/reference) of dabigatran AUCinf and C max (90 % confidence interval) were 101.4 % (89.6-114.9 %) and 89.7 % (77.8-103.4 %), respectively, following administration of dabigatran EM with bosutinib (test) relative to dabigatran EM administered alone (reference). Six subjects receiving combination treatment reported a total of seven adverse events (AEs) versus none for subjects receiving monotherapy alone. All AEs were mild to moderate and considered treatment related. CONCLUSION: These data demonstrate that single doses of bosutinib do not affect dabigatran exposure, suggesting that bosutinib is not a clinical inhibitor of P-gp. TRIAL REGISTRATION: ClinicalTrials.gov NCT02102633. https://clinicaltrials.gov/ct2/show/NCT02102633?term=NCT02102633&rank=1.

Effect of aprepitant, a moderate CYP3A4 inhibitor, on bosutinib exposure in healthy subjects.

PURPOSE: Bosutinib is an oral, dual Src and Abl tyrosine kinase inhibitor (TKI) approved for the treatment of Philadelphia chromosome-positive chronic myeloid leukemia resistant or intolerant to prior TKI therapy. Bosutinib is primarily metabolized by cytochrome P450 (CYP) 3A4, suggesting drug interaction potential with other CYP3A4 modulators. This open-label, randomized, 2-sequence, 2-period crossover study assessed the effect of single-dose aprepitant, a moderate CYP3A4 inhibitor, on the single-dose pharmacokinetic profile of oral bosutinib 500 mg. METHODS: Nineteen healthy, fed adults received bosutinib (100 mg × 5) alone or coadministered with aprepitant (125 mg × 1) in each treatment period (with a ≥14-day washout); serial blood samples were analyzed. Safety was evaluated. RESULTS: Following coadministration of aprepitant with bosutinib, the area under the concentration-time curve from time zero extrapolated to infinity (AUCinf) and maximum plasma concentration (C max) were higher than in bosutinib alone (AUCinf, 4719 and 2268 ng•h/mL; C max, 146.0 and 94.94 ng/mL). For bosutinib with aprepitant versus bosutinib alone, mean terminal elimination half-life was similar (25.99 vs 27.79 h), time to C max was longer (6.02 vs 4.15 h), and apparent oral clearance (CL/F) was decreased (105.9 vs 220.4 L/h). The ratio of adjusted geometric means of AUCinf and C max for bosutinib with aprepitant relative to bosutinib alone were 199 % (90 % confidence interval, 167-237 %) and 153 % (127-184 %), respectively. Both treatments were well tolerated. CONCLUSION: In healthy volunteers, administering a single dose of aprepitant increased the AUC and C max following a single dose of bosutinib by 99 and 53 %, respectively. These results are consistent with a moderate CYP3A4 inhibitor effect of aprepitant on bosutinib (Trial Registration: ClinicalTrials.gov NCT02058277).

Abuse Potential Study of ALO-02 (Extended-Release Oxycodone Surrounding Sequestered Naltrexone) Compared with Immediate-Release Oxycodone Administered Orally to Nondependent Recreational Opioid Users.

Objective: To evaluate the abuse potential of ALO-02, an abuse-deterrent formulation comprising pellets of extended-release oxycodone hydrochloride surrounding sequestered naltrexone hydrochloride. Design: Randomized, double-blind, placebo-/active-controlled, 6-way crossover study, with naloxone challenge, drug discrimination, and treatment phases. Subjects: Nondependent, recreational opioid users. Methods: Oral administration of crushed and intact ALO-02, crushed immediate-release (IR) oxycodone, and placebo. Primary endpoints were Drug Liking and High measured on visual analog scales and reported as maximum effect (E max ) and area-under-the-effect-curve from 0 to 2 hours (AUE 0-2h ). Other pharmacodynamic, pharmacokinetic and safety assessments were included. Results: Drug Liking and High (E max ) for crushed oxycodone IR 40 mg were significantly higher compared with placebo, confirming study validity ( P < 0.0001). Drug Liking and High (E max, AUE 0-2h ) for crushed ALO-02 (40 mg/4.8 mg and 60 mg/7.2 mg) were significantly lower compared to corresponding doses of crushed oxycodone IR (40 and 60 mg; P < 0.0001). Likewise, Drug Liking and High (E max and AUE 0-2h ) for intact ALO-02 60 mg/7.2 mg were significantly lower compared with crushed oxycodone IR 60 mg ( P < 0.0001). Secondary pharmacodynamic endpoints and plasma concentrations of oxycodone and naltrexone were consistent with these results. Fewer participants experienced adverse events (AEs) after ALO-02 (crushed or intact: 71.1-91.9%) compared with crushed oxycodone IR (100%). Most common AEs following crushed ALO-02 and oxycodone IR were euphoric mood, pruritus, somnolence, and dizziness. Conclusions: The results suggest that ALO-02 (crushed or intact) has lower abuse potential than crushed oxycodone IR when administered orally in nondependent, recreational opioid users.

Intravenous abuse potential study of oxycodone alone or in combination with naltrexone in nondependent recreational opioid users.

BACKGROUND: ALO-02, comprising pellets of extended-release oxycodone surrounding sequestered naltrexone, is intended to deter abuse. OBJECTIVE: Determine the abuse potential of intravenous oxycodone combined with naltrexone, which represents simulated crushed ALO-02 in solution, compared with intravenous oxycodone in nondependent, recreational opioid users. METHODS: A randomized, double-blind, placebo-controlled, three-way crossover study with naloxone challenge, drug discrimination, and treatment phases. Intravenous treatments included oxycodone hydrochloride 20 mg, oxycodone hydrochloride 20 mg plus naltrexone hydrochloride 2.4 mg (simulated crushed ALO-02 20 mg/2.4 mg), or placebo (0.9% sodium chloride for injection). Primary end points were peak effects (Emax) and area under the effects curve within 2 h postdose (AUE0-2h) on drug liking and high visual analog scales. RESULTS: Thirty-three participants were randomized into treatment phase, and 29 completed all treatments. Study validity was confirmed with statistically significant differences in Emax for drug liking and high (p < 0.0001) between intravenous oxycodone and placebo. Intravenous simulated crushed ALO-02 resulted in significantly lower scores than oxycodone on drug liking (Emax: 58.2 vs. 92.4; AUE0-2h: 104.3 vs. 152.4) and high (Emax: 17.2 vs. 93.1; AUE0-2h: 12.0 vs. 133.6), respectively (p < 0.0001, all comparisons). More participants experienced adverse events after intravenous oxycodone (n = 27 [90%]) versus intravenous simulated crushed ALO-02 (n = 4 [12.5%]) or placebo (n = 2 [6.5%]). CONCLUSION: Intravenous administration of simulated crushed ALO-02 resulted in significantly lower abuse potential, as assessed by subjective ratings of drug liking and high, than intravenous oxycodone in nondependent, recreational opioid users. This suggests that injection of ALO-02 may not be as desirable to recreational opioid users compared with oxycodone taken for nonmedical reasons.

Open-label, 2-period sequential drug interaction study to evaluate the effect of a 100-mg dose of desvenlafaxine on the pharmacokinetics of tamoxifen when coadministered in healthy postmenopausal female subjects.

BACKGROUND: Potential drugdrug interactions are a concern for patients taking tamoxifen. OBJECTIVE: This study was designed to determine the effect of coadministering desvenlafaxine on tamoxifen pharmacokinetics. MATERIALS AND METHODS: This open-label, 2-period inpatient and outpatient study enrolled healthy, postmenopausal women. Period 1, day 1, subjects were administered tamoxifen 40 mg followed by 23 days of blood sampling for pharmacokinetic analyses. During period 2, subjects received desvenlafaxine 100 mg/d for 28 days; a single dose of tamoxifen 40 mg was administered with desvenlafaxine 100 mg on day 7, followed by 23 days of blood sampling. Pharmacokinetics of tamoxifen and its metabolites (AUC over infinite time (AUC(inf)), AUC to the last measurable concentration (AUC(last)), peak plasma concentration (C(max)) were compared for monotherapy vs. combination therapy using the ratio of adjusted mean differences. A superposition method was used in the statistical analysis of N-desmethyl-tamoxifen and endoxifen to address the carry-over observed for those metabolites. The test for interaction was considered negative if the 90% confidence intervals (CIs) for the ratios were within 80 - 125%. RESULTS: Coadministration of tamoxifen with steady-state desvenlafaxine did not alter tamoxifen AUC(inf), AUC(last), and C(max), as reflected by the ratio of adjusted geometric means (90% CIs) of 100.7% (96.7%, 104.9%), 103.5% (100.2%, 106.9%), and 99.4% (94.0%, 105.2%), respectively. Similarly, coadministration did not alter 4-hydroxy- tamoxifen and N-desmethyl-amoxifen pharmacokinetics. The 11.8% (88.2% (82.6%, 94.2%)) and 8.0% (92.0% (84.7%, 100.0%)) decreases in endoxifen AUC(last) and C(max), respectively, were not significant (90% CIs fell wholly within the prespecified acceptance range). CONCLUSIONS: Steady-state desvenlafaxine 100 mg did not affect tamoxifen pharmacokinetics. For women treated with tamoxifen, desvenlafaxine may represent a safe and effective treatment unlikely to alter tamoxifen efficacy.

A Drug-Drug Interaction Study to Evaluate the Impact of Rimegepant on OCT2- and MATE1-Mediated Transport of Metformin in Healthy Participants.

Rimegepant is a calcitonin gene-related peptide receptor antagonist approved for migraine treatment. This phase 1, open-label, single-center, fixed-sequence study evaluated the effect of rimegepant on the pharmacokinetics (PK) of metformin. Twenty-eight healthy participants received metformin 500 mg twice daily from Days 1 to 4 and Days 7 to 10, and once daily on Days 5 and 11. Rimegepant, 75 mg tablet, was administered once daily from Days 9 to 12. At pre-specified time points, plasma metformin concentration, serum glucose levels, and safety and tolerability were evaluated. A 16% increase in the area under the plasma metformin concentration-time curve (AUC) for 1 dosing interval (AUC0-τ,ss), a statistically insignificant increase in maximum and minimum steady-state metformin concentration (Cmax,ss and Cmin,ss), and a decrease in metformin renal clearance were observed on Day 11 following metformin-rimegepant coadministration compared with metformin alone; however, the changes were not clinically relevant. Additionally, coadministration of rimegepant with metformin did not induce clinically meaningful change in the maximum observed glucose concentration (Gmax) or AUCgluc compared with metformin alone. Overall, rimegepant and metformin coadministration did not result in clinically relevant changes in metformin PK, renal clearance, or the antihyperglycemic effects of metformin. Rimegepant is considered safe for use with metformin.

Evaluation of the effect of modafinil on the pharmacokinetics of encorafenib and binimetinib in patients with BRAF V600-mutant advanced solid tumors.

BACKGROUND: A clinical drug-drug interaction (DDI) study was designed to evaluate the effect of multiple doses of modafinil, a moderate CYP3A4 inducer at a 400 mg QD dose, on the multiple oral dose pharmacokinetics (PK) of encorafenib and its metabolite, LHY746 and binimetinib and its metabolite, AR00426032. METHODS: This study was conducted in patients with BRAF V600-mutant advanced solid tumors. Treatment of 400 mg QD modafinil was given on Day 15 through Day 21. Encorafenib 450 mg QD and binimetinib 45 mg BID were administered starting on Day 1. PK sampling was conducted from 0 to 8 h on Day 14 and Day 21. Exposure parameters were calculated for each patient by noncompartmental analysis and geometric least-squares mean ratio. Corresponding 90% confidence intervals were calculated to estimate the magnitude of effects. RESULTS: Among 11 PK evaluable patients, encorafenib Cmax and AUClast were decreased in presence of steady-state modafinil by 20.2% and 23.8%, respectively. LHY746 exposures were not substantially changed in the presence of steady-state modafinil. CONCLUSION: The results from this clinical study indicate modafinil 400 mg QD had a weak effect on encorafenib PK. Based on these results, encorafenib can be coadministered with a moderate CYP3A4 inducer without dosing adjustment. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03864042, registered 6 March 2019.

No clinically relevant electrocardiogram effects in a randomized TQT study of single therapeutic/supratherapeutic rimegepant doses in healthy adults.

A single-center, phase I, partially double-blind (double-blind regarding doses of rimegepant and placebo, and open label with respect to moxifloxacin), randomized, 12-sequence, four-period crossover study of therapeutic (75 mg) and supratherapeutic (300 mg) doses of rimegepant with placebo and moxifloxacin (400 mg) controls was designed to evaluate drug effect on the Fridericia corrected QT (QTcF) interval in healthy fasted adults. A total of 38 participants were randomized and dosed in the study. Electrocardiogram (ECG) data were available from 37 participants in the rimegepant 75-mg group, 38 participants in the rimegepant 300-mg group, and 36 participants in the moxifloxacin and placebo groups. Both the 75- and 300-mg doses of rimegepant had no clinically relevant effect on ECG parameters, including QTcF, heart rate, PR and QRS interval, T-wave morphology, and U-wave presence. All upper 90% confidence intervals for the QTcF effect with rimegepant were less than or equal to 4.69 ms, well below the 10-ms threshold for potential clinical significance. Assay sensitivity was demonstrated by the QT effect of moxifloxacin. Using both by-timepoint and concentration-QTc analysis, a placebo-corrected change-from-baseline QTcF greater than 10 ms could be excluded for rimegepant plasma concentrations up to ~10,000 ng/mL, representing concentrations at least 10.8-fold the maximum observed concentration of the 75-mg therapeutic dose of rimegepant.

Reduced hepatic impairment study to evaluate pharmacokinetics and safety of zavegepant and to inform dosing recommendation for hepatic impairment.

Zavegepant, a high-affinity, selective, small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist, is approved in the United States for acute treatment of migraine in adults. The effects of moderate hepatic impairment (8 participants with Child-Pugh score 7-9 points) on the pharmacokinetics of a single 10-mg intranasal dose of zavegepant versus eight matched participants with normal hepatic function were evaluated in a phase I study. Pharmacokinetic sampling determined total and unbound plasma zavegepant concentrations. Moderate hepatic impairment increased the exposure of total zavegepant (~2-fold increase in AUC0-inf and 16% increase in Cmax) versus normal hepatic function, which is not considered clinically meaningful. The geometric least squares mean ratios (moderate impairment/normal) of plasma zavegepant AUC0-inf and Cmax were 193% (90% confidence interval [CI]: 112, 333; p = 0.051) and 116% (90% CI: 69, 195; p = 0.630), respectively. The geometric mean fraction unbound of zavegepant was similar for participants with moderate hepatic impairment (0.13; coefficient of variation [CV] 13.71%) versus those with normal hepatic function (0.11; CV 21.43%). Similar exposure findings were observed with unbound zavegepant versus normal hepatic function (~2.3-fold increase in AUC0-inf and 39% increase in Cmax). One treatment-emergent adverse event (mild, treatment-related headache) was reported in a participant with normal hepatic function. No dosage adjustment of intranasal zavegepant is required in adults with mild or moderate hepatic impairment.

Clinical Evaluation of the Effect of Encorafenib on Bupropion, Rosuvastatin, and Coproporphyrin I and Considerations for Statin Coadministration.

BACKGROUND AND OBJECTIVES: Encorafenib is a kinase inhibitor indicated for the treatment of patients with unresectable or metastatic melanoma or metastatic colorectal cancer, respectively, with selected BRAF V600 mutations. A clinical drug-drug interaction (DDI) study was designed to evaluate the effect of encorafenib on rosuvastatin, a sensitive substrate of OATP1B1/3 and breast cancer resistance protein (BCRP), and bupropion, a sensitive CYP2B6 substrate. Coproporphyrin I (CP-I), an endogenous substrate for OATP1B1, was measured in a separate study to deconvolute the mechanism of transporter DDI. METHODS: DDI study participants received a single oral dose of rosuvastatin (10 mg) and bupropion (75 mg) on days - 7, 1, and 14 and continuous doses of encorafenib (450 mg QD) and binimetinib (45 mg BID) starting on day 1. The CP-I data were collected from participants in a phase 3 study who received encorafenib (300 mg QD) and cetuximab (400 mg/m2 initial dose, then 250 mg/m2 QW). Pharmacokinetic and pharmacodynamic analysis was performed using noncompartmental and compartmental methods. RESULTS: Bupropion exposure was not increased, whereas rosuvastatin Cmax and area under the receiver operating characteristic curve (AUC) increased approximately 2.7 and 1.6-fold, respectively, following repeated doses of encorafenib and binimetinib. Increase in CP-I was minimal, suggesting that the primary effect of encorafenib on rosuvastatin is through BCRP. Categorization of statins on the basis of their metabolic and transporter profile suggests pravastatin would have the least potential for interaction when coadministered with encorafenib. CONCLUSION: The results from these clinical studies suggest that encorafenib does not cause clinically relevant CYP2B6 induction or inhibition but is an inhibitor of BCRP and may also inhibit OATP1B1/3 to a lesser extent. Based on these results, it may be necessary to consider switching statins or reducing statin dosage accordingly for coadministration with encorafenib. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03864042, registered 6 March 2019.

Tigecycline does not prolong corrected QT intervals in healthy subjects.

We evaluated the effect of tigecycline (50-mg and 200-mg doses) on corrected QT (QTc) intervals and assessed safety and tolerability in a randomized, placebo-controlled, four-period crossover study of 48 (44 male) healthy volunteers aged 22 to 53 years. Fed subjects received tigecycline (50 mg or 200 mg) or placebo in a blinded fashion or an open-label oral dose of moxifloxacin (400 mg) after 1 liter of intravenous fluid. Serial electrocardiograms were recorded before, and for 96 h after, dosing. Blood samples for tigecycline pharmacokinetics were collected after each recording. QTc intervals were corrected using Fridericia's correction (QTcF). Pharmacokinetic parameters were calculated using noncompartmental methods with potential relationships examined using linear mixed-effects modeling. Adverse events were recorded. The upper limits of the 90% confidence interval for the mean difference between both tigecycline doses and placebo for all time-matched QTcF interval changes from baseline were <5 ms. The tigecycline concentrations initially declined rapidly and then more slowly. In the group given 50 mg of tigecycline, the pharmacokinetic parameters and means were as follows: maximum concentration of drug in serum (C(max)), 432 ng/ml; area under the concentration-time curve from time zero extrapolated to infinity (AUC0-∞), 2,366 ng · h/ml; clearance (CL), 21.1 liters/h; volume of distribution at steady state (V(ss)), 610 liters; and terminal half-life (t(1/2)), 22.1 h. Proportional or similar values were found for the group given 200 mg of tigecycline. Linear mixed-effects modeling failed to show an effect on QTcF values by tigecycline concentrations (P = 0.755). Tigecycline does not prolong the QTc interval in healthy subjects. This study has been registered at ClinicalTrials.gov under registration no. NCT01287793.

The evaluation of potential pharmacokinetic interaction between sirolimus and tacrolimus in healthy volunteers.

PURPOSE: Sirolimus and tacrolimus are immunosuppressive compounds that have been used concomitantly in renal transplant patients. Both drugs are dosed orally and have common intestinal and hepatic metabolism and intestinal transport mechanisms. As such, there is a potential for pharmacokinetic drug interaction. METHODS: A single-dose, open-label, four-period, four-treatment, randomized crossover study was conducted in 27 healthy fasting volunteers. Each subject received a 15-mg oral dose of sirolimus alone, a 10-mg oral dose of tacrolimus alone, sirolimus and tacrolimus administered simultaneously, and tacrolimus administered 4 h before sirolimus. Whole blood and plasma samples for sirolimus and tacrolimus testing were analyzed by liquid chromatography/tandem mass spectrometry. Pharmacokinetic parameters were assessed using noncompartmental methods and were compared using analysis of variance (ANOVA). RESULTS: The geometric mean ratio and 90 % confidence interval (CI) area under the concentration-time curve from time 0 to infinity (AUCinf) for sirolimus administered simultaneously with tacrolimus versus sirolimus alone were 97 and 89-106, respectively, and, when administered in a staggered approach versus sirolimus alone, 107 and 98-117, respectively. The geometric mean ratio (%) and 90 % CI AUCinf for tacrolimus administered simultaneously with sirolimus versus tacrolimus alone were 92 and 82-102, respectively, and, when administered in a staggered approach versus tacrolimus alone, 94 and 84-105, respectively. CONCLUSIONS: The results of this study demonstrate a lack of any clinically important drug interaction between sirolimus and tacrolimus in healthy subjects after single-dose administration. However, due to the complexity of anti-rejection immunosuppressive therapy dosing, we suggest that sirolimus and tacrolimus concentration monitoring be performed when changes in dosing are made for either drug regimen.

Repeat-dose sirolimus pharmacokinetics and pharmacodynamics in patients with hepatic allografts.

PURPOSE: To determine sirolimus steady-state pharmacokinetics, and to assess the relationship between time-normalized trough sirolimus concentration (C(min,TN)) and evidence of efficacy (rejection and death) and adverse reactions (stomatitis and pneumonia) in liver allograft patients. METHODS: Dense sampling of sirolimus was performed over a single daily-dosing interval in 11 hepatic allograft recipients on day 28 and at 3 months after start of treatment. Serial trough concentration sampling was performed in 380 hepatic allograft recipients on days 1, 7, 14, 28, 42, 60, 90, 180, 270 and 360 after start of treatment. Occurrence of stomatitis, pneumonia, rejection, and death were collected for 360 days after start of treatment. Noncompartmental pharmacokinetic parameters were analyzed in the 11 densely sampled patients; C(min,TN) was determined in the 380 patients. RESULTS: Mean maximum concentration (C(max)), time to C(max) (t(max)), area under the curve for the given dose interval (AUC(tau)), and whole blood oral clearance at 3 months were 20.8 ± 7.6 ng/mL, 3 ± 1 h, 338 ± 144 ng·h/mL, and 10.0 ± 5.6 L/hr, respectively. In the 11 densely sampled patients, linear regression showed that C(min,TN) was highly predictive of AUC(tau) (r² = 0.77, P < 0.0001) at each analysis time point. Logistic regression showed a relationship between C(min,TN) in the 380 patients and pneumonia occurrence, but not between C(min,TN) and stomatitis, rejection, or death. CONCLUSIONS: In this study, the pharmacokinetic profile of sirolimus in hepatic allograft patients was consistent with that of renal transplantation recipients. With the exception of pneumonia, no correlation was observed between C(min,TN) and the occurrence of adverse events of interest.

Evaluation of Proton Pump Inhibitor Esomeprazole on Crizotinib Pharmacokinetics in Healthy Participants.

Crizotinib is a small-molecule, multitargeted tyrosine kinase inhibitor that exhibits decreased aqueous solubility at a higher pH. This open-label, randomized, phase 1 study (NCT01549574) evaluated the effect of multiple doses of the proton pump inhibitor esomeprazole on the pharmacokinetics (PK) of crizotinib and the safety of crizotinib with or without esomeprazole in healthy adults. Participants received a single 250-mg crizotinib dose after overnight fast or a single 250-mg crizotinib dose following esomeprazole 40 mg/day for 5 days. After a washout of ≥14 days, participants crossed over to the alternate treatment. Blood samples for plasma analysis were taken up to 144 hours after crizotinib dosing and relevant PK parameters estimated. Safety was assessed in all participants receiving ≥1 dose of study medication. Fifteen participants were evaluable for PK and safety for each treatment. Coadministration with esomeprazole resulted in a slight decrease (≈10%) in the crizotinib geometric mean area under the plasma concentration-time profile from time 0 to infinity (adjusted geometric mean ratio, 89.81% [90% confidence interval, 79.05-102.03]). Coadministration of esomeprazole did not affect peak crizotinib exposure. Adverse events (AEs) occurred in similar numbers between treatments; no serious or severe AEs occurred. The most common AE was diarrhea. Although esomeprazole decreased total exposure of crizotinib, it is not considered clinically meaningful, and dose modification is not required when crizotinib is coadministered with agents that affect gastric pH.

Excretion of moxidectin into breast milk and pharmacokinetics in healthy lactating women.

Moxidectin, registered worldwide as a veterinary antiparasitic agent, is currently under development for humans for the treatment of onchocerciasis in collaboration with the World Health Organization. The objective of this study was to assess the pharmacokinetics of moxidectin in healthy lactating women, including the excretion into breast milk. Twelve women, ages 23 to 38 years, weighing 54 to 79 kg, all more than 5 months postpartum, were enrolled, following their plan to wean their infants and provision of informed consent. A single 8-mg, open-label dose was administered orally after consumption of a standard breakfast. Complete milk collection was done for approximately 28 days, and plasma samples were collected for 90 days. Moxidectin concentrations were measured by high-performance liquid chromatography (HPLC) with fluorescence detection, with a validated range of 0.08 to 120 ng/ml. Noncompartmental pharmacokinetic methods were used to find the following results: peak concentration in plasma (C(max)), 87 ± 25 ng/ml; time to C(max) (t(max)), 4.18 ± 1.59 h; terminal-phase elimination half-life (t(1/2)), 832 ± 321 h; total area under the concentration-time curve (AUC), 4,046 ± 1,796 ng · h/ml; apparent oral dose clearance (CL/F), 2.35 ± 1.07 l/h; ratio of CL/F to the terminal-phase disposition rate constant, λ(z) (Vλ(z)/F), 2,526 ± 772 liters; percentage of maternal dose excreted in milk, 0.701 ± 0.299%; absolute amount excreted in milk, 0.056 ± 0.024 mg; relative infant dose, 8.73 ± 3.17% of maternal dose assuming complete absorption; clearance in milk (CL(milk)), 0.016 ± 0.009 liter/h. Nine of 12 subjects reported adverse events, all of which were considered treatment emergent but not drug related and were mostly reported during the long outpatient period 8 to 90 days after dose administration. The most frequently reported adverse events were headache and nausea (n = 4), oropharyngeal pain (n = 2), rhinitis, viral pharyngitis, and viral upper respiratory tract infection (n = 2).

Bioequivalence of Metformin in Ertugliflozin/Metformin Fixed-Dose Combination Tablets to Canadian-Sourced Metformin Coadministered With Ertugliflozin Under Fasted and Fed States.

A fixed-dose combination (FDC) product of a selective sodium-glucose cotransporter 2 inhibitor ertugliflozin and immediate-release metformin is approved for type 2 diabetes mellitus in the United States, European Union countries, Canada, and other countries. Two studies were conducted to assess the bioequivalence of metformin in the ertugliflozin/metformin FDC tablets to the corresponding doses of Canadian-sourced metformin (Glucophage) coadministered with ertugliflozin. Both studies were phase 1 randomized, open-label, 2-period, single-dose crossover studies (n = 32) in which healthy subjects received an ertugliflozin/metformin FDC tablet (2.5/500 mg or 7.5/850 mg) and the respective doses of the individual components (ertugliflozin coadministered with Canadian-sourced metformin) under fasted (n = 18) or fed (n = 14) conditions. Blood samples were collected 72 hours postdose to determine metformin concentrations. The 90% confidence intervals were within the bioequivalence acceptance criteria for the adjusted geometric mean ratios (FDC:coadministered) for metformin area under the plasma concentration-time curve from time zero to time t, where t is the last point with a measurable concentration and peak observed plasma concentration for both dose strengths under fasted and fed conditions. All study medications were well tolerated. Bioequivalence was demonstrated for the metformin component of the ertugliflozin/metformin FDC tablets and the corresponding doses of the Canadian-sourced metformin coadministered with ertugliflozin.

Phase I Pharmacokinetic Study of Fixed-Dose Combinations of Ibuprofen and Acetaminophen in Healthy Adult and Adolescent Populations.

INTRODUCTION: A fixed-dose combination (FDC) of ibuprofen and acetaminophen has been developed that provides greater analgesic efficacy than either agent alone at the same doses without increasing the risk for adverse events. METHODS: We report three clinical phase I studies designed to assess the pharmacokinetics (PK) of the FDC of ibuprofen/acetaminophen 250/500 mg (administered as two tablets of ibuprofen 125 mg/acetaminophen 250 mg) in comparison with its individual components administered alone or together, and to determine the effect of food on the PK of the FDC. Two studies in healthy adults aged 18-55 years used a crossover design in which subjects received a single dose of each treatment with a 2-day washout period between each. In the third study, the bioavailability of ibuprofen and acetaminophen from a single oral dose of the FDC was assessed in healthy adolescents aged 12-17 years, inclusive. RESULTS: A total of 35 and 46 subjects were enrolled in the two adult studies, respectively, and 21 were enrolled in the adolescent study. Ibuprofen and acetaminophen in the FDC were bioequivalent to the monocomponents administered alone or together. With food, the maximum concentration (Cmax) for ibuprofen and acetaminophen from the FDC was reduced by 36% and 37%, respectively, and time to Cmax (i.e. tmax) was delayed. Overall drug exposure to ibuprofen or acetaminophen in the fed versus fasted states was similar. In adolescents, overall exposure to acetaminophen and ibuprofen was comparable with that in adults, with a slightly higher overall exposure to ibuprofen. Exposure to acetaminophen and ibuprofen in adolescents aged 12-14 years was slightly higher versus those aged 15-17 years. Adverse events were similar across all treatment groups. CONCLUSIONS: The FDC of ibuprofen/acetaminophen 250/500 mg has a PK profile similar to its monocomponent constituents when administered separately or coadministered, indicating no drug-drug interactions and no formulation effects. Similar to previous findings for the individual components, the rates of absorption of ibuprofen and acetaminophen from the FDC were slightly delayed in the presence of food. Overall, adolescents had similar exposures to acetaminophen and ibuprofen as adults, while younger adolescents had slightly greater exposure than older adolescents, probably due to their smaller body size. The FDC was generally well tolerated.

Pharmacokinetic Properties of Single and Multiple Doses of Ertugliflozin, a Selective Inhibitor of SGLT2, in Healthy Chinese Subjects.

Ertugliflozin, a sodium-glucose cotransporter 2 inhibitor for the treatment of type 2 diabetes mellitus, prevents renal glucose reabsorption resulting in urinary glucose excretion. This open-label, parallel cohort, randomized study conducted in healthy Chinese adults residing in China assessed the pharmacokinetics, tolerability, and safety of 5 mg and 15 mg of ertugliflozin following single (fasted condition) and multiple-dose (fed condition) administration. Sixteen subjects were randomized and completed the study. Ertugliflozin absorption was rapid, with maximum plasma concentrations observed 1 hour after dosing under fasted conditions and 2 to 4 hours after dosing under fed conditions. Following single- and multiple-dose administration, ertugliflozin exhibited dose-proportional exposures with an apparent mean terminal half-life of approximately 9.5 to 11.9 hours. Steady state was reached after 4 once-daily doses. The accumulation ratio based on the area under the plasma concentration-time curve after multiple-dose administration was approximately 1.3 and 1.2 for ertugliflozin 5 mg and 15 mg, respectively. Ertugliflozin was generally well tolerated following administration of single and multiple oral doses of 5 mg and 15 mg in healthy Chinese subjects. Pharmacokinetic comparison with non-Asian subjects indicated that there are no clinically meaningful racial differences and no dose modification of ertugliflozin is required based on race or body weight.