Pharmacokinetics and Safety of Eptinezumab in Healthy Chinese Participants: A Randomized Clinical Trial.

BACKGROUND AND OBJECTIVE: Most evidence suggests that the pharmacokinetics of monoclonal antibodies (mAbs) are not meaningfully altered by patient characteristics, including racial/ethnic differences. Nevertheless, the pharmacokinetic profile of eptinezumab has not been evaluated in a Chinese population. This study was designed to confirm the hypothesis that the pharmacokinetic profile of the anti-calcitonin gene-related peptide mAb, eptinezumab, is similar in healthy Chinese individuals to that of healthy non-Asian individuals and non-Asian patients with migraine. METHODS: Over a study period of 12 weeks, healthy adult Chinese participants (N = 20) were randomized (1:1) to receive a single intravenous dose of eptinezumab 100 mg (n = 10) or 300 mg (n = 10) in a prospective, single-site, open-label parallel-group trial. Blood samples for the evaluation of plasma eptinezumab concentrations were obtained over 84 days, and standard pharmacokinetic parameters were derived. RESULTS: Mean maximum plasma concentrations (Cmax) of eptinezumab occurred 1.0-1.5 h post start of infusion, were similar between the 100 mg and 300 mg dose groups, and slowly declined in a biphasic manner. Cmax and area under the drug concentration-time curve (AUC) increased in a dose-proportional manner. Volume of distribution and clearance were similar between the 100 mg and 300 mg dose groups, and half-life was 22.5-28.1 days. Eptinezumab was generally well tolerated with no new safety signals identified. Only one participant, randomized to the 100 mg dose group, was positive for eptinezumab anti-drug antibodies, but negative for neutralizing antibodies, with no impact on pharmacokinetics. CONCLUSION: The pharmacokinetic profile of eptinezumab in healthy Chinese individuals was generally similar to that reported for non-Asian populations with migraine, and eptinezumab was generally well tolerated. Evaluation of immunogenicity showed no evidence of an impact of anti-drug antibodies or neutralizing antibodies on safety profiles. This supports the globally approved doses of 100 mg and 300 mg as being appropriate for Chinese patients with episodic migraine or chronic migraine.

Bioavailability of probucol from lipid and surfactant based formulations in minipigs: influence of droplet size and dietary state.

The influence of droplet size on the absorption from lipid and surfactant based formulations was evaluated from two self-emulsifying formulations, a surfactant solution, and an oil solution. The self-emulsifying formulations was a self-emulsifying (SEDDS) and a self-nanoemulsifying (SNEDDS) formulation containing equal lipid and surfactant load, but exhibiting a large difference (approx 100 times) in the mean particle diameter of the resultant emulsion. The formulations were evaluated in a bioavailability study in fasted and fed Göttingen minipigs using probucol as model drug. In order to determine the bioavailability, an oil-in-water emulsion was included as i.v. formulation. The fasted group was fasted overnight and offered the first daily meal approx 4 h after treatment. The fed group was offered the first daily meal (50% energy from fat) 30 min prior to treatment. In the fasted group the SNEDDS exhibited a slightly faster absorption and higher bioavailability than the SEDDS, though non-significant. Furthermore, the bioavailability from the surfactant solution and the oil solution were slightly lower compared to the SNEDDS, indicating that both small particle size and digestibility are important in ensuring optimal bioavailability. Comparing the absorption in fasted and fed minipigs showed that probucol exhibited no significant food effect, when formulated in a lipid and surfactant based formulations.

PET measurement of serotonin transporter occupancy: a comparison of escitalopram and citalopram.

The selective serotonin reuptake inhibitor (SSRI) citalopram (R,S-citalopram) is a racemic compound of two enantiomers. On the basis of in-vitro studies, inhibition of the human serotonin transporter (5-HTT) is achieved by the S-enantiomer (S-citalopram or escitalopram). The aim of the present PET study was to compare 5-HTT occupancy after single equimolar doses (with respect to S-enantiomer) in humans in vivo using R,S-citalopram (20 mg) and S-citalopram (10 mg) using PET and the radioligand [(11)C]MADAM. The design was a single-dose, double-blind, two-way crossover study in eight healthy male subjects. The 5-HTT binding potential at baseline and after single doses of study drugs was used to calculate 5-HTT occupancy in seven brain regions. Serum concentrations of the study drugs were determined in order to calculate the apparent inhibition constant (K(i),(app)), a secondary parameter of interest for the comparison. In all brain regions examined, occupancy was numerically higher after treatment with R,S-citalopram [66+/-19% to 78+/-17% (mean+/-s.d.) depending on the region] than after S-citalopram (59+/-15% to 69+/-13%; overall comparison: F=14.8, d.f.=1, 90, p<0.001). In line with this the apparent inhibition constant was significantly lower for R,S-citalopram than for S-citalopram (overall comparison: F=6.7, d.f.=1, 90, p<0.05). The small but significant difference in occupancy and K(i),(app) found between R,S-citalopram and S-citalopram suggests that not only S-citalopram but also R-citalopram to some degree occupies the 5-HTT in the human brain in vivo.