Dose Ranging Study of the Safety and Efficacy of R115966 in Plaque Psoriasis

PASI75 success at Visit 6 was defined as number of participants who achieved at least 75% reduction in PASI scores at Visit 6 compared to Visit 2 (Baseline). The PASI score was determined through evaluation of body surface area (BSA) covered by plaque psoriasis in four regions (head/neck, upper extremities, trunk and lower extremities). This assessment included a combination of both degree of involvement (assessed as per the % of affected body area using a 7-point scale that ranged as 0 (0% involvement), 1 = 1-9%, 2 = 10-29%, 3 = 30-49%, 4 = 50-69%, 5 = 70-89% and 6 = 90-100%) and severity (evaluated individually using a 5-point scale that ranged as 0 = No evidence of sign, 1 = slight evidence of sign, 2 = moderate evidence of sign, 3 = marked evidence of sign and 4 = very marked, most severe evidence of sign) of erythema, induration and desquamation in each of the same four regions. PASI score ranged from 0 to 72 in 0.1-unit intervals; higher scores indicating worse psoriasis.

PASI50 success was defined as number of participants who achieved at least 50% reduction in PASI scores at each post baseline visit (Visit 3 to 8) compared to Visit 2 (Baseline). The PASI score was determined through evaluation of BSA covered by plaque psoriasis in four regions (head/neck, upper extremities, trunk and lower extremities). This assessment included a combination of both degree of involvement (assessed as per the % of affected body area using a 7-point scale that ranged as 0 (0% involvement), 1 = 1-9%, 2 = 10-29%, 3 = 30-49%, 4 = 50-69%, 5 = 70-89% and 6 = 90-100%) and severity (evaluated individually using a 5-point scale that ranged as 0 = No evidence of sign, 1 = slight evidence of sign, 2 = moderate evidence of sign, 3 = marked evidence of sign and 4 = very marked, most severe evidence of sign) of erythema, induration and desquamation in each of the same four regions. PASI score ranged from 0 to 72 in 0.1-unit intervals; higher scores indicating worse psoriasis.

The IGA was used to assess the overall severity of a participant's plaque psoriasis at a particular time point and the evaluation took into consideration the three individual characteristics of plaque psoriasis (scaling, plaque elevation, and erythema). The IGA was recorded using a scale that ranged from 0 (clear), 1 = almost clear, 2 = mild, 3 = moderate to 4 (severe) in whole-unit increments; higher scores indicating worse psoriasis. Investigators did not refer to previous evaluations when conducting the IGA assessment. At every study visit, the investigator evaluated each participant's plaque psoriasis and recorded the one integer grade that best described the average, overall severity of the condition. Investigators were trained not to refer to previous assessments of the IGA, and not to base the IGA scores on any component of the PASI. Individual body regions were not assessed (as in the PASI), but rather a global evaluation for each participant at each visit was determined.

PASI75 success was defined as number of participants who achieved at least 75% reduction in PASI scores at each post baseline visit (Visit 3 to Visit 8) except Visit 6. The PASI score was determined through evaluation of BSA covered by plaque psoriasis in four regions (head/neck, upper extremities, trunk and lower extremities). This assessment included a combination of both degree of involvement (assessed as per the % of affected body area using a 7-point scale that ranged as 0 (0% involvement), 1 = 1-9%, 2 = 10-29%, 3 = 30-49%, 4 = 50-69%, 5 = 70-89% and 6 = 90-100%) and severity (evaluated individually using a 5-point scale that ranged as 0 = No evidence of sign, 1 = slight evidence of sign, 2 = moderate evidence of sign, 3 = marked evidence of sign and 4 = very marked, most severe evidence of sign) of erythema, induration and desquamation in each of the same four regions. PASI score ranged from 0 to 72 in 0.1-unit intervals; higher scores indicating worse psoriasis.