N-Acetyl-L-Cysteine or Acetylcysteine is a well known medication useful as a mucolytic and for the treatment of acetaminophen intoxication when administered by oral and/or intravenous route.
Mucolytic treatment consists in acetylcysteine oral administration of daily amounts comprised between 200 mg and 800 mg divided in 2 or 3 doses.
For the treatment of acetaminophen overdoses, the therapy involves emptying the gastrointestinal tract with ipecac or by means of lavage with a large-bore tube. If drug blood levels exceed 250 μg/mL four hours after ingestion, the overdose is probably severe. Because hepatotoxicity is caused by a gluthathione-depleting metabolite of acetaminophen, the sulfhydryl donor acetylcysteine is an effective antidote. Acetylcysteine is given orally as five percent solution diluted with three volumes of a soft drink. The initial loading dose is 140 mg/kg; thereafter a dose of 70 mg/kg is given every four hours for an additional 17 doses. If the patient is unable to swallow, the solution is administered by gastric or enteral tube. Treatment is most effective when it is begun within eight hours of ingestion but can still be beneficial if it is delayed for as long as 24 hours. In one series of 2,540 poisonings, there were no deaths among persons who received the antidote within 16 hours. Intravenous acetylcysteine (300 mg/kg, given during a 20 hour period) has been used in Europe and Canada. The 72 hour oral treatment appears to be as effective as the 20 hour intravenous regimen.
In both these conditions it is believed that acetylcysteine when taken orally is, via hepatic metabolisation, a source of glutathione a natural tripeptide circulating antioxidant. Therefore mucolytic and acetaminophen detoxification activities are de factum the results of the action of glutathione, and the acetylcysteine is given as a precursor (source) of the glutathione.
U.S. Pat. No. 4,847,282 discloses water-soluble acetylcysteine salts, useful as mucolytic agents, consisting of the reaction products of acetylcysteine with at least one basic amino-acid, the later being preferably selected from the group comprising arginine, lysine, histidine and ornithine. These water soluble salts, having a neutral pH are suitable for pulmonary administration. Also the patent discloses that these new salts of acetylcysteine do not produce bronchospasms, contrary to the parent product acetylcysteine, when administered to the lungs.
EP Patent Application 0876814A1 and PCT/BE03/00048 discloses inhalation pharmaceutical preparations and devices suitable for pulmonary administration of active drugs and in particular the highly soluble basic amino salts of acetylcysteine. One example of such salts is L-Lysine-N-Acetylcysteinate, also called Nacystelyn or NAL.
Pharmaceutical compositions derived from these 2 patents teach pharmaceutical compositions useful to administer acetylcysteine or a salt thereof, directly to the lungs and/or nose. This very effective method of administration is safe since it does not produce bronchospasms.
A new clinical trial has been performed with a dry powder inhaler (DPI) formulation of NAL in moderate to severely ill COPD patients. The study was performed with two doses of NAL DPI: 20 mg twice a day and 40 mg twice a day versus placebo.
The complete title of the study was “A 12-week, multicentre, randomised, double-blind, placebo controlled, pilot study of the safety and efficacy of Nacystelyn (20 mg b.i.d. and 40 mg b.i.d.) in patients with chronic obstructive pulmonary disease (COPD).”
NAL pulmonary administration was performed using a Dry Powder Inhaler consisting of a capsule containing NAL and a carrier, and of an inhalation device.
The primary end-point of the study was to evaluate the effect of NAL, versus placebo, on the quality of life in COPD patients between baseline values (T0) and after 12 weeks of treatment (T12).
During the same study, sputum of COPD patients was collected at baseline (T0), after 4 weeks (w4) and after 12 weeks of treatment (T12).
The purpose of collecting sputum was to assess if NAL DPI administration could affect (increase or decrease) lung inflammation parameters in such patients. Lung inflammation may be reflected by the sputum concentration of some pro-inflammatory markers, called cytokines, such as interleukine 6 (IL-6) and interleukine 8 (IL-8) or anti-inflammatory markers, such as interleukine 10 (IL-10).
It is understood that, the lower the concentration of pro-inflammatory markers in the lung, the lower the lung inflammation status.
After collection of the mucus, the said mucus was centrifugated and the cytokines IL-8 and IL-6 were quantified using a validated analytical method. The results are presented in Table I. It should be noted that only subjects presenting a quantifiable value of cytokines at the time considered were taken into account.
As seen, NAL induces a decrease of IL-6 in the sputum of COPD patients in a dose related manner. After 12 weeks of treatment, the concentration in IL-6 decreased by 17% and 42% respectively after administration of NAL 20 mg or 40 mg while the levels of IL-6 increased by 51% after administration of placebo for 12 weeks. NAL is also able to significantly decrease the IL-8 levels in the sputum. However, for this marker, the maximal effect is obtained with the 20 mg dose. Indeed, after 12 weeks of treatment of NAL 20 mg and 40 mg, the levels of IL-8 decreased by 17% and increased by 3% respectively, while during the same period, the levels of IL-8 in sputum of patients taking placebo increased by 29%.
So it has surprisingly been demonstrated in the present study that administration of Nacystelyn to patients with COPD is able to decrease the level of lung inflammation in those patients.
This is extremely surprising since the product was administered directly to the lungs, the NAL cannot be converted into GSH which is recognised by the scientific community as a substance with a known anti-inflammatory substance.
Number | Date | Country | |
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60528482 | Dec 2003 | US |
Number | Date | Country | |
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Parent | 12003694 | Dec 2007 | US |
Child | 12285724 | US | |
Parent | 11009017 | Dec 2004 | US |
Child | 12003694 | US |