, placebo-controlled studies in adults with chronic stable plaque psoriasis involving ≥ 10% of the body surface area, a minimum PASI of 10 and who had received or were candidates for systemic anti-psoriatic therapy or phototherapy. Patients with guttate, erythrodermic, or pustular psoriasis and patients with severe infections within 4 weeks of screening were excluded from study. No concomitant major anti-psoriatic therapies were allowed during the study.
Study I eva luated 672 patients who received placebo or ENBREL® SC at doses of 25 mg once a week, 25 mg twice a week or 50 mg twice a week for 3 months. After 3 months, patients continued on blinded treatments for an additional 3 months during which time, patients originally randomized to placebo began treatment with blinded ENBREL® at 25 mg twice weekly (designated as placebo/ENBREL® in Table 8); patients originally randomized to ENBREL® continued on the originally randomized dose (designated as ENBREL®/ENBREL® groups in Table 8).
Study II eva luated 611 patients who received placebo or ENBREL® SC at doses of 25 mg or 50 mg twice a week for 3 months. After 3 months of randomized blinded treatment, patients in all three arms began receiving open-label ENBREL® at 25 mg twice weekly for 9 additional months.
Response to treatment in both studies was assessed after 3 months of therapy and was defined as the proportion of patients who achieved a reduction in score of at least 75% from baseline by the Psoriasis Area and Severity Index (PASI). The PASI is a composite score that takes into consideration both the fraction of body surface area affected and the nature and severity of psoriatic changes within the affected regions (induration, erythema, and scaling).
Other eva luated outcomes included the proportion of patients who achieved a score of “clear” or “minimal” by the Static Physician Global Assessment (sPGA) and the proportion of patients with a reduction of PASI of at least 50% from baseline. The sPGA is a 6 category scale ranging from “5 = severe” to “0 = none” indicating the physician’s overall assessment of the psoriasis severity focusing on induration, erythema, and scaling. Treatment success of “clear” or “minimal” consisted of none or minimal elevation in plaque, up to faint red coloration in erythema, and none or minimal fine scale over < 5% of the plaque.
Patients in all treatment groups and in both studies had a median baseline PASI score ranging from 15 to 17; and the percentage of patients with baseline sPGA classifications ranged from 54% to 66% for moderate, 17% to 26% for marked, and 1% to 5% for severe. Across all treatment groups, the percentage of patients who previously received systemic therapy for psoriasis ranged from 61% to 65% in Study I, and 71% to 75% in Study II; and those who previously received phototherapy ranged from 44% to 50% in Study I, and 72% to 73% in Study II.
More patients randomized to ENBREL® than placebo achieved at least a 75% reduction from baseline PASI score (PASI 75) with a dose response relationship across doses of 25 mg once a week, 25 mg twice a week and 50 mg twice a week (Table 8 and 9). The individual components of the PASI (induration, erythema, and scaling) contributed comparably to the overall treatment-associated improvement in PASI.
Table 8: Study I Outcomes at 3 and 6 Months *
p = 0.001 compared with placebo.
†
p < 0.0001 compared with placebo.&nbs |
