Researchers lead by Yusheng Qiu, MD, head, department of respiratory medicine, Glenfield Hospital, Leicester, United Kingdom, hypothesized that treating patients with fluticasone/salmeterol 500/50 mcg for 12 weeks could reduce relevant inflammation in the airways as measured by CD8+, CD45+ CD4+, CD68+, and mast cells found in bronchial biopsies.

Although lung function decreases as the concentrations of CD8+ lymphocytes increases, previous studies demonstrated that inhaled corticosteroids alone have no effect on airway inflammation.

Following a 3-week run-in period, the researchers obtained biopsy samples from all 140 subjects with COPD, mean age 64 years. Patients carried on with 1 more week of run-in therapy before being randomized to receive either the Serevent (n = 73) or a placebo (n = 67). Second biopsies were taken after 12 weeks of treatment.

Patients were excluded if that had a history of asthma or any other respiratory disease other than COPD.

Results show that compared with placebo subjects, patients on Serevent had important reductions in the levels of most inflammatory cells and pro-inflammatory cytokines associated with the development and progression of COPD, Dr. Qiu said.

For example, CD8+ cells were reduced by 45% compared with baseline in the Serevent group and by 7.8% in the placebo group (P = .001). The absolute difference in numbers of CD8+ cells was 118 cells/mm² between the two groups.

The analysis also found that CD4+ cell count was reduced from 95 cells/mm² to 43 cells/mm² in the Serevent group, while the count increased by 2.7% in the placebo group, from 75 cells/mm² to 94 cells/mm². This corresponds to a treatment difference of 40% in favor of Serevent (P = .002), Dr. Qiu said.

While CD45+ lymphocyte levels increased by 3.2% from baseline in the placebo group, they decreased by 30% in the Serevent group (P = .001).

Overall, Dr Qiu said, the differences in reductions in CD4+ and CD8+ T-lymphocytes were statistically significant, as were the changes in cells expressing mRNA for tumor necrosis factor a and interferon IFN gamma.

These anti-inflammatory effects may contribute to the clinical and therapeutic benefit seen with Serevent, Dr. Qiu commented. Although this part of the study was only designed to observe the changes in inflammatory cells and markers, a further part of the study showed significant changes in lung function such as forced expiratory volume in 1 second, among subjects treated with Serevent.

Reiterating that past studies have shown no effect from inhaled steroids alone at reducing airway inflammation, he said these data show that while reducing the markers of inflammation is not a steroid effect, he cannot conclude that the benefit is caused by salmeterol alone.

Serevent is manufactured by GlaxoSmithKline


[Presentation title: Anti-Inflammatory Effects of Salmeterol/Fluticasone Propionate (SFC) on Airway T-lymphocyte Populations in COPD. Abstract1325]

Copyright © 2009 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content.