Phase I study of the pharmacokinetics and safety of single and multiple doses of intravenous N-acetylcysteine in healthy Chinese subjects.

OBJECTIVE: The aim of the study was to determine the pharmacokinetics (PK) and safety of single and repeat doses of intravenous (IV) N-acetylcysteine (NAC) in Chinese subjects. PATIENTS AND METHODS: A total of 24 healthy male and female Chinese subjects aged 19-40 years were enrolled in this open-label phase I study. All subjects received a single dose of NAC 600 mg IV on day 1 and, after a 3-day washout, received repeat doses of NAC 600 mg IV (twice daily on days 4 and 5 and once on day 6). RESULTS: Following a single dose, plasma NAC concentrations peaked rapidly, starting to fall at the end of the 5-minute infusion in a multiphasic manner. Mean Cmax was 83.30 µg/mL (CV% 30.7%), median Tmax was 0.083 h (range 0.08-0.25 h), and mean AUC(0-12 h) was 81.87 h*µg/mL (CV 14.0%). Following repeat dosing, Cmax was approximately 20% higher than after a single dose, with similar Tmax. Total exposure AUC(0-12) was 13% higher at steady state than after single dosing. The accumulation ratio was approximately 1.13, indicating only a slight accumulation with multiple dosing. NAC was eliminated with T1/2 of approximately 8 hours. Around 15% of the total NAC dose was excreted in the urine in the 32 hours post-dose, keeping with extensive NAC metabolism and transformation. Renal clearance of NAC was 995.2 mL/h (CV 50.2%). IV NAC was well tolerated after both single and multiple dosing. CONCLUSIONS: This is the first robust study evaluating the PK and safety of IV NAC 600 mg in Chinese subjects and provides important data if this agent is to be used IV as a mucolytic in this population.

Methylene blue MMX® tablets for chromoendoscopy. Bioavailability, colon staining and safety in healthy volunteers undergoing a full colonoscopy.

Methylene blue-MMX® tablets are proposed as an aid for detection and visualisation of adenomas and carcinomas in patients undergoing colonoscopy, by improving their detection rate and highlighting the presence of the intestinal dysplastic lesions. Single total doses of 100 and 200 mg were administered to healthy volunteers undergoing a bowel cleansing preparation and a full colonoscopy to investigate the colonic staining. The pharmacokinetics of methylene blue and the safety after exposure to the tablets were also investigated. With 200 mg, the best staining, assessed as the sum of acceptable and good staining, was achieved in the ascending colon and rectosigmoid (75% subjects each), the transverse and the descending colon (approximately 63% each). Absence of staining or overstaining were reported for no colonic region of interest in any subject. Similar results were observed in the 100 mg dose group. Methylene blue blood concentrations reached a peak (Cmax) in a median time (Tmax) of 12 h with 100 mg and 16 h with 200 mg. AUC0-t was 10.7 ±â€¯6.7 µg/mLxh after 100 mg and 25.2 ±â€¯7.4 µg/mLxh after 200 mg. Half-life ranged between 9 and 22 h after the lower dose and between 6 and 26 h after the higher dose. The cumulative urinary excretion was about 28% after 100 mg and about 39% after 200 mg up to 60 h post-dose. The overall frequency of adverse events after single dose of the test product administered along with a bowel cleansing preparation was 39%, but only one was related to the test product: abnormal transaminases. The most frequent adverse event was a transient polyuria (17%). One serious adverse event (gastrointestinal haemorrhage) led the subject to study discontinuation and hospitalisation and another subject withdrew the study due to one adverse event (haematemesis). Either event was not related to methylene blue.

Methylene blue MMX tablets for chromoendoscopy. Safety tolerability and bioavailability in healthy volunteers.

Methylene blue-MMX tablets are proposed as colonic diagnostic staining. Methylene blue taken prior to colonoscopy is expected to provide an effective staining of colonic and rectal mucosa leaving unstained the dysplastic or polypoid areas. The present single dose, open-label study investigated the safety of methylene blue after single oral doses of 200 and 400mg in healthy volunteers. The absolute bioavailability was also investigated after the intake of 2L of bowel cleansing preparation in 2h and by comparing the dose of 200mg with a single iv dose of 100mg in the same subjects. Only non-serious adverse events occurred. Related events occurred to 8/22 subjects. Most of the events were mild and transient. Abnormal transaminases, gastrointestinal disorders and dysuria frequency were 13.6%. After intake of the laxative and the oral dose of 200mg, systemic exposure to methylene blue was shown in all subjects with concentrations increasing for 12h. The peak was reached in a median of 16 h. Peak blood concentration did not increase proportionally with the dose. AUC(0-t) was 32.94 µg/mL × h after 200mg and 38.08 µg/mL × h after 400mg. Half life ranged between 14 and 27 h after the lower dose and between 6 and 26 h after the higher dose. The cumulative excretion was about 40% of the injected dose, 39.67% after 200mg and 23.48% after 400mg. Absolute bioavailability of methylene blue calculated as ratio between AUC(0-t) oral/iv corrected for the dose was on average F(abs)=139.19 ± 52.00%.

Clinical trial: Preliminary efficacy and safety study of a new Budesonide-MMX® 9 mg extended-release tablets in patients with active left-sided ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory disease with relapses. Many patients need systemic corticosteroids to induce clinical remission. AIM: Efficacy and safety of Budesonide-MMX® 9 mg tablets, a new oral, extended-release formulation, were evaluated in patients suffering from active, left-sided UC with colitis activity index (CAI) <14. METHODS: 36 patients were treated once daily for 4 weeks with Budesonide-MMX® 9 mg tablets or placebo. In an additional 4-week period, all patients received Budesonide-MMX®. CAI, endoscopic index and histology were assessed after 4 and 8 weeks. Primary end-point was remission, and/or CAI reduction by 50% after 4 weeks. Morning cortisol was assayed after 4 and 8 weeks, and a short ACTH-test was performed at week 8. RESULTS: 32 patients were analysed. After 4 weeks, 47.1% of the patients in the Budesonide-MMX® 9 mg tablets group achieved the primary end-point vs. 33.3% of patients on placebo. In addition, 47.1% of budesonide patients and another 33.3% of placebo recipients improved without remission by 4 weeks. The CAI reduction was significant with Budesonide (p<0.0001) tablets and not with placebo (p=0.1). Neither morning cortisol nor pituitary-adrenal axis was more frequently suppressed with Budesonide tablets than with placebo. CONCLUSIONS: Budesonide-MMX® 9 mg tablets induced a fast and significant clinical improvement of active left-sided UC without suppression of adrenocortical functions and without important toxicity EudraCT number 2004-000896-33.