Effect of opicapone multiple-dose regimens on levodopa pharmacokinetics

AIMS

To compare the levodopa/carbidopa (LC) and levodopa/benserazide (LB) pharmacokinetic profiles following repeated doses of opicapone (OPC) administered apart from levodopa.

METHODS

Two randomized, double blind, sex-balanced, placebo-controlled studies in four groups of 12 or 18 healthy subjects each. In each group, enrolled subjects received a once-daily morning (5, 15 and 30 mg) or evening (5, 15 and 50 mg) administration of OPC or placebo for up to 28 days. On the morning of Day 11, 12 h after the OPC or placebo evening dose, or the morning of Day 21, 1 h after the OPC or placebo dose, a single dose of immediate-release 100/25 mg LC was administered. Similarly, on Day 18 morning, 12 h after the OPC or placebo evening dose, or Day 28 morning, 1 h after the OPC or placebo dose, a single dose of immediate-release 100/25 mg LB was administered.

RESULTS

All OPC treatments, in relation to the placebo group, presented a higher extent of exposure (AUC) to levodopa following either LC or LB doses. A relevant but not dose-dependent increase in the levodopa AUC occurred with all OPC dose groups in relation to placebo. All active treatments significantly inhibited both peak (Emax ) and extent (AUEC) of the catechol-O-methyltransferase activity in relation to placebo. The tolerability profile was favourable.

CONCLUSION

Opicapone, as once-daily oral evening regimen and/or 1 h apart from levodopa therapy, increases the bioavailability of levodopa associated with its pronounced, long-lasting and sustained catechol-O-methyltransferase inhibition. The tolerability profile was favourable and similar between OPC and placebo.

Pharmacodynamic interactions of a solid formulation of sodium oxybate and ethanol in healthy volunteers

AIM

The pharmacologic effects of sodium oxybate (SO) have a number of similarities with those of alcohol. This study evaluated the pharmacodynamic interaction of SMO.IR (a solid immediate release formulation of SO) and alcohol (0.7 (males) or 0.57 (females) g kg(-1) alcohol using 40% vodka).

METHODS

In a randomized, double-blind, double-dummy, crossover trial, 24 healthy volunteers received randomly a) 2.25 g SMO.IR and placebo alcohol preparation, b) 2.25 g f SMO.IR and alcohol, c) 2.25 g SMO.IR matching placebo and alcohol and d) 2.25 g of SMO.IR matching placebo and placebo alcohol preparation. Objective and subjective cognitive parameters, adverse events and vital signs were assessed before, 15 and 165 min after treatment administration.

RESULTS

Alcohol produced the expected cognitive impairment and the expected subjective sedation rapidly after intake (from 15 min). The objective effects of SMO.IR were much less pronounced than those of alcohol. The reverse was observed for subjective complaints, which were related to lesser stimulation and greater sedation. Nevertheless, 165 min after administration this sedation feeling was less with SMO.IR than with alcohol. There was a significant interaction between SMO.IR and alcohol at 15 min (i.e. increase in alertness and stimulation and decrease in sedation). In addition, an isolated mild decrease in digit vigilance accuracy occurred at 165 min post-dose after the combination. The co-administration of SMO.IR and alcohol was safe and well-tolerated.

CONCLUSION

SMO.IR and alcohol have distinct adverse effect profiles. The objective effects of SMO.IR are much less marked than those of alcohol. No deleterious interaction was observed.

The Milieu Intérieur study - an integrative approach for study of human immunological variance

The Milieu Intérieur Consortium has established a 1000-person healthy population-based study (stratified according to sex and age), creating an unparalleled opportunity for assessing the determinants of human immunologic variance. Herein, we define the criteria utilized for participant enrollment, and highlight the key data that were collected for correlative studies. In this report, we analyzed biological correlates of sex, age, smoking-habits, metabolic score and CMV infection. We characterized and identified unique risk factors among healthy donors, as compared to studies that have focused on the general population or disease cohorts. Finally, we highlight sex-bias in the thresholds used for metabolic score determination and recommend a deeper examination of current guidelines. In sum, our clinical design, standardized sample collection strategies, and epidemiological data analyses have established the foundation for defining variability within human immune responses.

Interaction between brivaracetam (100 mg/day) and a combination oral contraceptive: a randomized, double-blind, placebo-controlled study

This randomized, double-blind, placebo-controlled, two-way crossover study aimed to assess the pharmacokinetic interactions between brivaracetam 100 mg/day and a combination oral contraceptive (OC) containing 30 μg ethinylestradiol and 150 μg levonorgestrel. The study was performed in 28 healthy women over five 28-day menstrual cycles: baseline (OC only), two treatment cycles with brivaracetam (50 mg b.i.d.) or placebo coadministered with OC separated by a wash-out cycle (OC only), and a follow-up cycle (OC only). The OC was administered on days 1-21 of each cycle, and brivaracetam or placebo on days 1-28 of the treatment cycles. Pharmacokinetics of ethinylestradiol and levonorgestrel were determined on day 20; brivaracetam morning trough levels on days 20 (with OC) and 29 (without OC) were compared. Cmax (maximum plasma concentration) and AUC (area under the plasma concentration versus time curve) ratios for brivaracetam versus placebo (90% confidence interval [CI]) were 0.96 (0.88-1.04) and 0.90 (0.86-0.95) for ethinylestradiol, and 0.95 (0.91-0.99) and 0.92 (0.88-0.97) for levonorgestrel, within predefined bioequivalence limits (0.80-1.25). Brivaracetam trough levels were similar on days 20 and 29 (ratio 1.08; 90% CI 0.98-1.18). No differences in breakthrough bleeding were seen across the five cycles. It was concluded that there were no interactions between brivaracetam 100 mg/day and the OC.

Similar immunogenicity of the A/H1N1 2009 pandemic influenza strain when used as a monovalent or a trivalent vaccine

BACKGROUND

The WHO recommended including the A (H1N1) 2009 pandemic strain in the influenza vaccines for use in the 2010-2011 northern hemisphere (NH) influenza season. The immunogenicity and safety of the trivalent split inactivated vaccine (Vaxigrip®) NH 2010-2011 formulation was compared to that observed for the corresponding non-adjuvanted monovalent A (H1N1) pandemic vaccine (Panenza®), when tested in similar populations of adult and elderly volunteers.

METHODS

The monovalent vaccine was evaluated in two clinical trials, conducted respectively in both adult and elderly subjects and in a population of adults. The trivalent vaccine was evaluated in a clinical study that enrolled both adult and elderly subjects. Antibody titers were measured in serum samples drawn at day 0 (before vaccination) and 21 days after one vaccine injection using the same hemagglutination inhibition (HI) assay method. The occurrence of adverse events was reported up to 21 days after vaccination.

RESULTS

Before immunization in the three studies, most of the volunteers had antibody titers below seroprotective levels against the pandemic A(H1N1) 2009 virus. After vaccination, in each trial and in each age group, high seroprotection rates, GMT ratios and seroconversion rates were observed. Seroprotection rates after administration of the monovalent vaccine reached 93% and 98% in the adult groups, and 83.7% in the elderly group. After administration of the trivalent vaccine, seroprotection rates of 92.2% and 81.3% were obtained respectively in the adult and the elderly groups. No related serious adverse events and no safety signals were detected either with the monovalent or trivalent vaccine.

CONCLUSION

Comparable immunogenicity profiles were observed in three clinical trials of the pandemic A(H1N1) 2009 strain when formulated either as a monovalent or as a component of a seasonal trivalent vaccine.

[Effects of Diprivan on cerebral blood flow, intracranial pressure and cerebral metabolism in head injured patients]

The effects of propofol on cerebral blood flow, intracranial pressure (ICP) and cerebral oxygen consumption (CMRO2) were assessed in ten severely head-injured patients undergoing surgery for limb fractures. The patients, aged between 15 and 40 years, were in deep coma, scored 6-7 on the Glasgow coma score. They were mechanically ventilated and sedated with 1 mg.h-1 phenoperidine. Anaesthesia was carried out with a 2 mg.kg-1 intravenous bolus of propofol, immediately followed by a 150 micrograms.kg-1.min-1 infusion, which lasted for a mean time of 41.4 +/- 7.3 min. Data were collected 5 min before any propofol was given, 15 min after the start of the infusion, and 15 min after its end. A radial artery cannula, a 7.5 Fr thermodilution flow-directed pulmonary arterial catheter, a cerebral intraventricular catheter and a catheter in the jugular venous bulb were used for this purpose. Carotid arterial injection of 133Xenon was used to determine regional cerebral blood flow (rCBF). Anaesthetic blood concentrations of propofol (3 to 5 micrograms.ml-1) were associated with a decrease in all the parameters studied: cerebral perfusion pressure, from 82 +/- 14 mmHg to 59 +/- 7 mmHg (p less than 0.001); rCBF, from 35 +/- 6 ml.100 g-1.min-1 to 26 +/- 5 ml.100 g-1.min-1 (p less than 0.01); ICP from 11.3 +/- 2.6 mmHg to 9.2 +/- 2.5 mmHg (p less than 0.001); CMRO2 from 1.63 +/- 0.38 mlO2 +/- 100 g-1.min-1 to 1.18 +/- 0.38 mlO2.100 g-1.min-1 (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of propofol on cerebral hemodynamics and metabolism in patients with brain trauma

The authors determined the effect of propofol on cerebral blood flow, intracranial pressure, and cerebral arteriovenous oxygen content difference in severely brain-injured patients during orthopedic treatment of fractures of the extremities. The Glasgow Coma Scale score was 6 or 7 at the time of the study. Data were collected in the operating room before and during (5 and 15 min) administration of propofol (2 mg/kg iv bolus immediately followed by a 150 micrograms.kg-1.min-1 infusion) before surgical stimulation. Propofol was infused during 41.4 +/- 7.3 min. After operation, the last set of measurements was made 15 min after propofol was stopped. The study was performed on 10 adults (age range, 15-40 yr) whose lungs were mechanically ventilated (air/O2) and who were sedated (phenoperidine, 1 mg/h), and was conducted using a radial artery cannula; a 7.5-Fr, thermodilution, flow-directed, pulmonary artery catheter; an intraventricular catheter; and a catheter in the jugular venous bulb. The 133xenon intra-internal carotid artery injection technique was used to determine regional cerebral blood flow (rCBF). Anesthetic blood concentration of propofol (3-5 micrograms/ml) was associated with decreases in cerebral perfusion pressure (CPP; from 82 +/- 14 to 59 +/- 7 mmHg; P less than 0.001), rCBF (from 35 +/- 6 to 26 +/- 5 ml.100 g-1.min-1; P less than 0.001), and intracranial pressure (ICP; from 11.3 +/- 2.6 to 9.2 +/- 2.5 mmHg; P less than 0.001). Cerebrovascular resistance and cerebral arteriovenous oxygen content difference were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

[Peroperative autotransfusion]

Intraoperative autotransfusion was used in 15 patients undergoing peripheral vascular, porta-caval and liver surgery. This technique is blood saving in these indications. The most important physiopathological consequence is disseminated intravascular coagulation, whatever anticoagulation protocol is used. Low-dose heparin continuously administered is considered.