Findings from an international, phase-3 clinical study comparing the efficacy and safety of Stelara (ustekinumab) with etanercept (Enbrel) in the treatment of moderate to severe plaque psoriasis appear in The New England Journal of Medicine. The results showed a significantly higher clinical response with both doses of Stelara than with etanercept over a 12-week period. The first-of-its-kind head-to-head study comparing two biologic agents for plaque psoriasis also shows the efficacy of Stelara among patients in the study who failed to respond to etanercept.

Psoriasis is an inflammatory disorder characterized by raised, inflamed, red lesions, or plaques, which can cause physical pain. It is estimated that approximately 7.5 million Americans and nearly 3 per cent of the world's population are living with psoriasis, which can present in various forms, ranging from mild to severe and disabling.

"This study provides important comparative efficacy information about the treatment of moderate to severe plaque psoriasis with two biologic agents," said professor Christopher Griffiths, FRCP, University of Manchester, Manchester, UK, and lead trial investigator. "We observed a substantial proportion of patients achieving high levels of skin clearance with ustekinumab, both through the study's primary endpoint at week 12 and following crossover from etanercept, including in those patients who showed a lack of response to etanercept during the study."

In the comparator study, 68 and 74 per cent of patients receiving subcutaneous injections of Stelara (45 mg or 90 mg) at weeks zero and four achieved at least a 75 per cent reduction in psoriasis as measured by the Psoriasis Area and Severity Index (PASI 75) at week 12, the primary endpoint, compared with 57 per cent of patients receiving subcutaneous injections of 50 mg etanercept twice per week for 12 weeks (P = 0.01 for Stelara 45 mg; P < 0.001 for Stelara 90 mg, each compared with etanercept). Onset of clinical response appeared more rapidly among Stelara-treated patients, with higher numbers of patients achieving PASI 75 by week eight compared with patients receiving etanercept.

Investigators also reported that a greater proportion of patients receiving Stelara achieved a marked improvement in psoriasis as assessed by PASI 90 response, or nearly complete clearance of psoriasis. At week 12, 36 per cent of patients receiving Stelara 45 mg and 45 per cent of patients receiving Stelara 90 mg achieved PASI 90 compared with 23 per cent of patients receiving etanercept (P < 0.001 for each comparison versus etanercept). Moreover, a greater proportion of patients in both the Stelara 45 mg and 90 mg treatment groups achieved a Physician Global Assessment (PGA) score of 'cleared' or 'minimal' (65 per cent and 71 per cent, respectively) compared with patients in the etanercept treatment group (49 per cent).

Stelara, a human interleukin (IL)-12 and IL-23 antagonist, is approved for the treatment of adult patients (18 years or older) with moderate to severe plaque psoriasis who are candidates for phototherapy or systemic therapy.