A global Phase 3 study of Enbrel (etanercept) demonstrated that a significant number of psoriasis patients given initial loading doses of Enbrel for three months rapidly achieved psoriasis clearing and then maintained the response while receiving half the drug dose.

In this double-blind, placebo-controlled study, 583 patients with moderate to severe psoriasis were randomized to receive placebo (n=193), 25 mg of Enbrel twice weekly (n=196), or a loading dose of 50 mg of Enbrel twice weekly (n=194), for 12 weeks. Following this initial period, patients then continued treatment for an additional 12 weeks. During the second 12 weeks, those taking the loading dose of Enbrel were "stepped down" to half the dose (25 mg twice weekly), while patients taking 25 mg twice weekly continued with the same dose. Patients initially taking placebo were started on 25 mg Enbrel twice weekly. As previously reported, patients in both groups initially receiving Enbrel experienced improvement in psoriasis in as early as two weeks.

The new data show that during the second 12 weeks of the study, Enbrel continued to provide significant relief of psoriasis symptoms in all groups. Forty-nine per cent of patients treated with the loading dose achieved 75 per cent improvement in the Psoriasis Area Severity Index (also known as PASI 75) in the first 12 weeks of the study as compared to 34 per cent of patients taking 25 mg twice weekly and three per cent of patients taking placebo. A large majority (77 per cent) of the patients treated with the loading dose who had achieved a PASI 75 response at week 12 maintained this response through week 24 while receiving the stepped down dose. In addition, at week 24, the percentage of step down patients achieving PASI 75 increased to 54 per cent.

"In this study, more step down patients achieved the clinical milestone of PASI 75 by week 12," said Craig Leonardi, clinical associate professor of dermatology at Saint Louis University. "It was very exciting to see that a large majority of these patients maintained the effect while receiving half the loading dose."

"Psoriasis is a chronic condition and patients must sometimes stop treatment due to life circumstances such as pregnancy or surgery," said Alice Gottlieb, director of the Clinical Research Center at University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School.