In a RCT conducted in 40 patients under mechanical ventilator due to exacerbation of COPD, the blood levels of IL-6, IL-8 and TNF-α did not differ between patients receiving daily administration of a glutamine solution for 5 days and those receiving administration of a placebo for the same period [63]. The gene discussed is CXCL8; the disease is chronic obstructive pulmonary disease.