Oral liarozole in the treatment of patients with moderate/severe lamellar ichthyosis: results of a randomized, double-blind, multinational, placebo-controlled phase II/III trial.

BACKGROUND: Oral liarozole, a retinoic acid metabolism-blocking agent, may be an alternative to systemic retinoid therapy in patients with lamellar ichthyosis. OBJECTIVE: To demonstrate the efficacy and safety of once-daily oral liarozole in the treatment of moderate/severe lamellar ichthyosis. METHODS: This was a double-blind, multinational, parallel phase II/III trial (NCT00282724). Patients aged ≥ 14 years with moderate/severe lamellar ichthyosis [Investigator's Global Assessment (IGA) score ≥ 3] were randomized 3 : 3 : 1 to receive oral liarozole (75 or 150 mg) or placebo once daily for 12 weeks. Assessments included: IGA; a five-point scale for erythema, scaling and pruritus severity; Short Form-36 health survey; Dermatology Life Quality Index (DLQI); and safety parameters. The primary efficacy variable was response rate at week 12 (responder: ≥ 2-point decrease in IGA from baseline). RESULTS: Sixty-four patients were enrolled. At week 12, 11/27 (41%; liarozole 75 mg), 14/28 (50%; liarozole 150 mg) and one out of nine (11%; placebo) patients were responders; the difference between groups (liarozole 150 mg vs. placebo) was not significant (P = 0.056). Mean IGA and scaling scores decreased from baseline in both liarozole groups at weeks 8 and 12 vs. placebo; erythema and pruritus scores were similar between treatment groups. Improvement in DLQI score was observed in both liarozole groups. Treatment with liarozole for 12 weeks was well tolerated. CONCLUSIONS: The primary efficacy variable did not reach statistical significance, possibly owing to the small sample size following premature termination. However, once-daily oral liarozole, 75 and 150 mg, improved scaling and DLQI and was well tolerated in patients with moderate/severe lamellar ichthyosis.

Development of a novel fluorescent microsphere technique to combine serial cerebral blood flow measurements with histology in the rat.

The aim of the study was to evaluate the microsphere technique for the quantitative assessment of regional cerebral blood flow (rCBF) at different time points in the same animal. Yellow-green and red fluorescent microspheres with a diameter of 15 microm were injected into the rat at two different time points via a cannula inserted into the left ventricle of the heart. The reproducibility of the rCBF measurements in normocapnic conditions (n=7) and the responsiveness of the flow to hypercapnia induced by 7% CO(2) (n=7) was examined. The fluorescent spheres were counted on 100 microm vibratome sections of perfusion-fixed brains and rCBF was calculated. The median total CBF in normocapnic rats was 224 ml/min/100 g for the first microsphere injection and 216 ml/min/100 g for the second one. In the hypercapnic group CBF amounted to 400 ml/min/100 g and after 30 min of normocapnia decreased to 178 ml/min/100 g. No differences between the left and right hemisphere were found and there was no indication that the first injection might have influenced the second one. The described approach allows combining the assessment of rCBF at different time points in physiological or pathological conditions with histological evaluation of related morphological alterations in the same brain region of the same animal.

Impaired autoregulation of cerebral blood flow in an experimental model of traumatic brain injury.

In order to study the pathophysiology and the intracranial hemodynamics of traumatic brain injury, we have developed a modified closed-head injury model of impact-acceleration that expresses several features of severe head injury in humans, including acute and long-lasting intracranial hypertension, diffuse axonal injury, neuronal necrosis, bleeding, and edema. In view of the clinical relevance of impaired autoregulation of cerebral blood flow after traumatic brain injury, and aiming at further characterization of the model, we investigated the autoregulation efficiency 24 h after experimental closed-head injury. Cortical blood flow was continuously monitored with a laser-Doppler flowmeter, and the mean arterial blood pressure was progressively decreased by controlled hemorrhage. Relative laser-Doppler flow was plotted against the corresponding mean arterial blood pressure, and a two-line segmented model was applied to determine the break point and slopes of the autoregulation curves. The slope of the curve at the right hand of the break point was significantly increased in the closed head injury group (0.751 +/- 0.966%/mm Hg versus -0.104 +/- 0.425%/mm Hg,p = 0.028). The break point tended towards higher values in the closed head injury group (62.2 +/- 20.8 mm Hg versus 46.9 +/- 12.7 mm Hg; mean +/- SD, p = 0.198). It is concluded that cerebral autoregulation in this modified closed head injury model is impaired 24 h after traumatic brain injury. This finding, in addition to other characteristic features of severe head injury established earlier in this model, significantly contributes to its clinical relevance.

Validation of a closed head injury model for use in long-term studies.

To study pharmacotherapy of traumatic brain injury in rats, a modified closed head injury model was used that expresses clinically relevant features including intracranial hypertension and morphological alterations. Long-term survival under ethically acceptable conditions would greatly improve its clinical relevance. To ensure this goal with great reproducibility, the experimental protocol was adapted, in particular the impact-acceleration kinetics. Variations in impact-acceleration conditions were obtained by modifying the stiffness of the impact site and changing the height of a 400 g weight dropped from 51.5 to 31.5 cm (51.5/400; 31.5/400). Impact and acceleration were measured with a force sensor incorporated in a rigid dummy-rat and an accelerometer mounted on the platform onto which the animals are positioned. Significant correlation was shown between impact and acceleration. Accelerations obtained in rats were significantly lower than those in the dummy. Unlike the 51.5/400 group, in the 31.5/400 group no mortality or cranial fractures were observed. In both groups intracranial pressure rose to pathological values immediately after trauma and remained elevated longer than 24 h. Diffuse axonal injury developed in all groups and remained present for at least 7 days. By reducing the impact-acceleration conditions, post-traumatic complications were diminished, while the clinically important features were maintained.

Economic evaluation of antifungal agents in the treatment of toenail onychomycosis in Germany.

BACKGROUND: The strategies for the management of onychomycosis have changed since the availability of the newer generation of antifungal agents, particularly, itraconazole and terbinafine. Itraconazole (1-week pulse) therapy may have higher efficacy and an improved adverse-effects profile compared to the continuous therapy regimen. OBJECTIVE: We performed a pharmacoeconomic evaluation of the most commonly used treatments in Germany for toenail onychomycosis from a health care payer perspective. METHODS: A 5-step approach was used. Firstly, the purpose of the study, the comparator drugs, their dosage regimens and the time frame of the analysis were defined. Next, the medical practice and resource consumption patterns associated with the treatment of onychomycosis were identified. In step III, a meta-analysis was used to determine the relative efficacy of the comparator drugs. In step IV, a decision tree of the treatment algorithms was constructed for each comparator. The expected cost analysis and cost-effectiveness analysis were also performed. Finally, a sensitivity analysis was carried out. RESULTS: For the four main comparator drugs used to treat toenail onychomycosis in Germany, the clinical response rates (clinical cure plus marked improvement) at the end of the follow-up period (month 12 after starting therapy) were, for itraconazole (1-week pulse dosing): 89.8 +/- 3% (mean +/- SE), terbinafine: 79.4 +/- 10%, itraconazole (continuous dosing): 77.5 +/- 9%, and ciclopirox nail varnish: 55 +/- 5%. Itraconazole (1-week pulse dosing) was most cost-effective at DM 1,107 per successful treatment, followed by oral terbinafine at DM 1,224, ciclopirox nail varnish and itraconazole (continuous dosing). Sensitivity analyses indicated that itraconazole (1-week pulse dosing) and terbinafine had similar cost-effectiveness ratios. CONCLUSION: Itraconazole is an effective, broad-spectrum triazole used as continuous or pulse therapy in the treatment of onychomycosis. Itraconazole (1-week pulse) and terbinafine are the most cost-effective therapies for toenail onychomycosis.

Photothrombosis in rabbit brain cortex: follow up by continuous pO2 measurement.

Continuous recording of changes in local pO2 during and after brain infarction in surviving animals which can be followed for months or years, may provide interesting information concerning pathophysiology and treatment of stroke and thrombosis. We performed such measurements before, during and till 4 weeks after photochemical induction of a cerebrocortical infarction in three rabbits. Rose bengal--a photosensitive dye which sticks to endothelial cells and gives rise to endothelial damage and thrombosis when illuminated--was injected intravenously. After injection, a circular area (diameter 3 mm) of the brain cortex was illuminated using an optic fiber conducting light from a halogen lamp, whether or not filtered by heat and colour filters. In order to enable pO2 measurement in and near the infarct zone, we constructed a transparent plastic frame in which pO2 electrodes were fixed beneath and 1 mm besides a shaft permitting mounting of the optic fiber. A black adhesive ring (inner diameter 3 mm) was attached to the bottom of the frame providing a perfectly demarcated illumination area. After fixation the electrodes were calibrated and the frame was implanted in the rabbit's skull. Ten days later an infarction was induced; pO2 was monitored continuously before, during and till 4 hours after this induction. Furthermore, pO2 was recorded 24 hours, 48 hours, 5 days, 14 days and 4 weeks after infarction. Parameters describing the time course of pO2 were determined. In the illuminated area pO2 decreased after a certain latency time to reach a very low level, probably zero level, where it remained for at least 24 hours. Gradually, recovery was observed during the following days, and four weeks after infarction both level and pattern of electrode current appeared to be normal again. In the border zone pO2 decreased but did not reach zero level. Recovery was observed earlier than in the illuminated area.

Construction, calibration and evaluation of pO2 electrodes for chronical implantation in the rabbit brain cortex.

Aiming at continuous polarographic measurement of the mean pO2 in the rabbit brain cortex before, during and after photochemically induced infarction, we designed and constructed monopolar platinum oxygen electrodes of the open type for chronical implantation. The measuring tip (length 1 mm, diameter 0.1 mm) is covered with a homogenous membrane of cellulose acetate. The electrode currents are measured by a four-channel amplifier of proper design; the device permits accurate and stable polarisation, identical for each channel. Moreover, a calibration device has been constructed. It consists of a Buchner funnel filled with Ringer solution and mounted in a temperature-controlled bath. In order to create a specific partial pressure of oxygen in the calibration chamber, predetermined gasmixtures are bubbled through the solution using computer controlled mass flow regulators. The calibration device thus permits the determination of primary and secondary electrode parameters, i.e. linearity, oxygen sensitivity and residual current, and polarisation dependency, temperature dependency, sensitivity to CO2, electrode stability, dynamic behaviour and oxygen consumption. Three groups, each of them containing ten electrodes, have been tested with regard to electrode parameters: the first group contains bare electrodes, the second and the third group contain membrane covered electrodes, with a membrane thickness of 10 and 20 microns respectively. In order to evaluate acute and long-term effects of implantation on the brain cortical tissue and on the sensors' measuring qualities, electrodes have been implanted for different time periods (51 days, 30 days, 9 days, 5 min). pO2 was recorded regularly and polarograms have been registered. The effects on cortical tissue have been studied with the aid of light microscopy.