Chronic plaque psoriasis patients who do not improve on their initial treatment with the targeted agent alefacept appear to respond well to a second course of treatment, according to research presented February 19th at the 63rd Annual Meeting of the American Academy of Dermatology.

About half the patients who showed little improvement in the signs and symptoms of their disease in the first try with alefacept were able to achieve significant improvement when treatment was re-initiated, said Alan Menter, MD, chairman of the Division of Dermatology at Baylor University Medical Center in Dallas, Texas.

Dr. Menter scrutinized data from patients enrolled in phase 3 studies of alefacept and in the open-label extensions of those studies to identify patients who failed to achieve a Psoriasis Area and Severity Index (PASI) 50 and those who failed to a achieve a PASI 25 with the first course of alefacept. Five hundred twenty-one patients received an initial course of alefacept by intravenous injection, and 457 received alefacept in an intramuscular injection.

“As part of the clinical development program of alefacept, patients who completed phase 2 and 3 studies were eligible to participate in open-label extension studies to determine the safety and efficacy of repeated courses of alefacept,” said Dr. Menter.

After a second course of alefacept, PASI improvement was observed in 93% of the patients who failed to achieve a PASI 50 with the first treatment and in 89% of patients who did not receive a PASI 25 after one course of treatment.

“Almost everyone responded to the second course of treatment,” Dr. Menter said during his poster discussion presentation. “Nineteen percent of patients who didn’t have a PASI 50 achieved a PASI 75 with a second course of treatment, and 53% achieved a PASI 50.” Improvements were also significant among patients who failed to achieve PASI 25 with one course - 14% achieved PASI 75 and 47% achieved PASI 50%. In the study, the mean age of patients was 45, and 70% were men. The median duration of psoriasis was 19 years, and the median body surface area involvement was 22%.

Dr. Menter included data from patients who received up to five courses of treatment and noted that the proportion of patients achieving PASI 75 increased from 29% with one course to a maximum of 54% during course five, while the proportion achieving PASI 50 increased from 56% during one course to 74% during course five.

He concluded that the “patient response to additional treatment with alefacept is incrementally beneficial regardless of response to the initial treatment.”

Dr. Menter also noted that patients who have not shown improvement with other biological agents also appear to do better when they are switched to alefacept. Phoebe Rich, MD, a clinical associate professor of dermatology at Oregon Health Sciences Center in Portland, Oregon, noted that alefacept takes longer to achieve a response than some of the other biologics, which might explain the improvement with multiple courses. Dr. Rich moderated the poster session where Dr. Menter presented his findings.

Dr. Menter’s study was funded Biogen Idec, Inc., of Cambridge, Massachusetts.

[Study title: Long-term use of alefacept: Efficacy and off-treatment responses in patients who have received multiple courses of therapy. Abstract P7]