The Salmeterol or Corticosteroids (SOCS) and the Salmeterol with and without Inhaled Corticosteriods (SLIC) Trials

Objectives:

These two randomized, placebo-controlled, blinded clinical trials were concurrently managed to determine whether Inhaled Corticosteriod (ICS) therapy can be reduced or eliminated in patients with persistent asthma after adding a long-acting Beta 2-agonist to their treatment regimen.

Background:

Treatment guidelines recommend the addition of long-acting Beta 2-agonists for patients with persistent asthma that is inadequately controlled through mild to moderate doses of inhaled corticosteroids (ICSs). No evidence exists, however, to support their use as monotherapy in adults with persistent asthma. The SOCS trial was initiated to determine the efficacy of salmeterol therapy as a replacement for ICS therapy. The SLIC trial sought to determine if the addition of a long acting beta 2-agonist permitted a reduction in dose, and/or elimination of, inhaled corticosteroids over time.

Subjects:

Patients were randomized to either the SOCS or SLIC trial at 6 Asthma Clinical Research Network sites after a 6 week run-in period in which patients were treated with inhaled triamcinolone acetonide (400 µg twice per day). Patients whose asthma was well-controlled at 4 weeks into the run-in period were randomized into the SOCS trial while patients whose asthma was not well-controlled were randomized into the SLIC trial. In the SOCS Study, one hundred sixty-four patients aged 12 through 65 years were randomized into one of three arms: 1) triamcinolone therapy, 2) salmeterol xinafoate, or 3) placebo. In the SLIC study, one hundred seventy-five patients aged 12 through 65 years initially continued the triamcinolone therapy. During a two-week salmeterol induction phase, 13 of every 15 patients received slameterol add-on therapy and two of every thirteen patients received placebo. After two weeks, half of patients assigned to salmeterol add-on therapy were randomly assigned to either maintain triamcinolone therapy or undergo a blinded, 1-step reduction in triamcinolone for the first 8 weeks followed by triamcinolone elimination.

Conclusions:

The results indicate that in patients with persistent asthma suboptimally controlled by triamcinolone therapy alone but whose asthma symptoms improve after addition of salmeterol, a substantial reduction (50%) in triamcinolone dose can occur without a significant loss of asthma control. However, total elimination of triamcinolone therapy results in a significant deterioration in asthma control and, therefore, cannot be recommended. (JAMA, 2001;285:2583-2593. JAMA, 2001;285:2594-2603.)