Continuation and long-term maintenance treatment with Hypericum extract WS® 5570 after recovery from an acute episode of moderate depression — A double-blind, randomized, placebo controlled long-term trial

The efficacy and safety of Hypericum extract WS® 5570 in preventing relapse during 6 months' continuation treatment and 12 months' long-term maintenance treatment after recovery from an episode of recurrent depression were investigated in a double-blind, placebo controlled multicenter trial. Adult out-patients with a recurrent episode of moderate major depression, a 17-item Hamilton Depression Rating Scale (HAMD) total score ≥ 20 and ≥ 3 previous episodes in 5 years participated. After 6 weeks of single-blind treatment with 3 × 300 mg/day WS® 5570 patients with score ≤ 2 on item ‘Improvement’ of the Clinical Global Impressions (CGI) scale and a HAMD total score decrease ≥ 50% versus baseline were randomized to 3 × 300 mg/day WS® 5570 or placebo for 26 weeks. 426 patients were evaluated for efficacy. Relapse rates during continuation treatment were 51/282 (18.1%) for WS® 5570 and 37/144 (25.7%) for placebo. Average time to relapse was 177 ± 2.8 and 163 ± 4.4 days for WS® 5570 and placebo, respectively (time-to-event analysis; p = 0.034; α = 0.025 one-sided). Patients treated with WS® 5570 showed more favorable HAMD and Beck Depression Inventory time courses and greater over-all improvement (CGI) than those randomized to placebo. In long-term maintenance treatment a pronounced prophylactic effect of WS® 5570 was observed in patients with an early onset of depression as well as in those with a high degree of chronicity. Adverse event rates under WS® 5570 were comparable to placebo. WS® 5570 showed a beneficial effect in preventing relapse after recovery from acute depression. Tolerability in continuation and long-term maintenance treatment was on the placebo level.