N-acetylcysteine (NAC) for the Treatment of Acute Exacerbation of COPD
Status:
Not yet recruiting
Trial end date:
2025-09-30
Target enrollment:
Participant gender:
Summary
Patients with Chronic obstructive pulmonary disease (COPD) experience gradually deteriorating
lung function, which may be complicated by acute exacerbations. N- acetylcysteine (NAC) is
frequently used in patients with COPD as a mucolytic. Besides its mucolytic effects,
high-dose NAC has additional benefits in patients with stable COPD, including improving lung
function and reducing exacerbations. Studies on the dose-dependent effects of NAC in COPD
patients showed a high dose of NAC was needed to achieve its antioxidant effects and clinical
benefits in COPD patients, whereas a dose of 600 mg once daily was not able to increase
glutathione levels. According to a study conducted in Hong Kong on patients with stable COPD,
1 year of treatment with high-dose NAC at 600 mg twice daily improved small airways function
in terms of forced expiratory flow and forced oscillation technique, and also significantly
reduced exacerbation frequency with a decreasing trend in admission rate. In a meta-analysis,
patients treated with NAC had significantly and consistently fewer exacerbations of COPD. The
role of NAC was examined in a Delphi consensus study involving 53 COPD experts from 12
countries. Respondents agreed that regular treatment with mucolytic agents could effectively
decrease the frequency of exacerbations and the duration of mild-to-moderate exacerbations,
while delaying the time to first exacerbation and increasing symptom-free time in COPD
patients. The panel also approved the doses of NAC with favourable side effect profiles to be
recommended for regular use in patients with a bronchitic phenotype.
However, there have been conflicting results regarding the efficacy of NAC for treating acute
exacerbation of COPD. NAC has not been included as an adjunct for the treatment of COPD
exacerbation in international guidelines. As NAC is relatively low cost, readily available,
and has a favourable side effect profile as a treatment for COPD exacerbation, it is
important to properly assess the clinical benefits of NAC as an adjunct to standard medical
treatments to hasten recovery. This study is a double-blind randomised controlled trial on
NAC as an adjunctive treatment for acute COPD exacerbation. It will assess the role of NAC in
the treatment of acute COPD exacerbation.