Distribution of Improvements in Psoriasis Area and Severity Index from the Phase 2 Trial of Risankizumab  
in Moderate to Severe Plaque Psoriasis
Bruce Strober,

1
 Kim A Papp,

2
 Mary Flack,

3
 Yihua Gu,

4
 Elizabeth H Z Thompson,

5
 Wendell C Valdecantos

4

1University of Connecticut Health Center and Probity Medical Research, Farmington, CT, USA; 2K Papp Clinical Research and Probity Medical Research, Waterloo, ON, Canada;  
3Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, CT, USA; 4AbbVie Inc., North Chicago, IL, USA; 5AbbVie Inc., Redwood City, CA, USA

INTRODUCTION

1. Papp KA, et al. N Engl J Med 2017; 376: 1551-60.

OBJECTIVE
• The objective of this analysis was to examine the distribution of 

PASI responses in patients from the phase 2 trial treated with 
risankizumab versus ustekinumab.

MATERIALS & METHODS

RESULTS

CONCLUSIONS
• The overall improvements in PASI scores at weeks 12 and 16 

were higher in patients treated with 90 or 180 mg risankizumab 
compared with ustekinumab.

• Patients treated with 90 or 180 mg risankizumab showed a greater 
shift in PASI distribution towards PASI 90-100 response rates 
compared with ustekinumab-treated patients.

• Risankizumab is a humanized IgG1 monoclonal antibody that inhibits 
IL-23 by binding its p19 subunit. In a phase 2 trial, risankizumab 
demonstrated superiority over ustekinumab in patients with moderate 
to severe plaque psoriasis.1

• Response rates derived from dichotomizing a continuous variable at a 
certain threshold (eg, 90% improvement in Psoriasis Area and Severity 
Index, PASI 90) are often used as primary endpoints in clinical trials to 
demonstrate efficacy of investigational products.

• However, additional visualization of the cumulative distribution of 
responses can help assess the consistency of PASI improvement at the 
population level.

STUDY DESIGN AND PATIENTS
• Patients (N=166) with moderate to severe plaque psoriasis were 

randomized to receive subcutaneous injections of risankizumab (18 mg  
single dose, 90 or 180 mg at weeks 0, 4, and 16) or ustekinumab  
(45 or 90 mg, based on body weight at weeks 0, 4, and 16, Figure 1).

Figure 1. Study Design of Phase 2 Trial of Risankizumab in 
Psoriasis Patients

REFERENCES

16Week 0 4 12 4824

= dose

Ra
nd

om
is

ed
 1

:1
:1

:1

Risankizumab 18 mg s.c.bN=43

N=40 Ustekinumab 45/90 mg s.c.a 

Risankizumab 180 mg s.c.N=42

N=41 Risankizumab 90 mg s.c.

1o Endpoint:  PASI 90 at Week 12

Double-Blind Period (N=166)

Follow-upc

a. Used as per label (45 mg or 90 mg in patients with body weight ≤100 kg or >100 kg at randomization, respectively). 
b. Placebo only at weeks 4 and 16. c. Patients who failed to achieve at least 50% improvement from baseline in PASI 
(<PASI 50) during the follow-up period (indicated by gray shading), were eligible to enter the OLE (NCT02203851).  
Abbreviations:  PASI=Psoriasis Area and Severity Index; q12w=every 12 weeks; s.c.=subcutaneous.

EFFICACY ANALYSES
• The proportions of patients achieving different levels of PASI responses 

were assessed at weeks 12 and 16 in an intent-to-treat population.
• Patients with a missing assessment were counted as non-responders 

for that assessment.
• Cumulative probability plots were generated to assess the distribution 

of changes from baseline in PASI score across treatment groups.

• The proportions of patients achieving PASI 75, PASI 90, and PASI 100 
responses are shown in Figure 2.

• At week 12, the proportions of patients achieving the primary end 
point of PASI 90 response were 30.2% (13/43), 73.2% (30/41), and 
78.6% (33/42) for 18 mg, 90 mg, and 180 mg risankizumab groups, 
respectively, compared with 40% (16/40) for ustekinumab-treated 
patients (Figure 2).1

Figure 2. PASI 75, PASI 90, and PASI 100 Response Rates 
Through Week 16 (NRI)

Week 0 Week 4 Week 8 Week 12 Week 16
0

10

20

30

40

50

60

70

80

90

100
Pa

tie
nt

s 
Ac

hi
ev

in
g 

PA
SI

 7
5 

(
)

Ustekinumab 45 90 mga (N 40)
Risankizumab 1  mga (N 43)
Risankizumab 90 mg (N 41)
Risankizumab 1 0 mg (N 42)

97.6
92.7

88.1 90.5

67.5
72.5

67.4
62.8

Week 0 Week 4 Week 8 Week 12 Week 16
0

10

20

30

40

50

60

70

80

90

100

Pa
tie

nt
s 

A
ch

ie
vi

ng
 P

A
SI

 9
0 

(
)

73.2
78.0

78.6 81.0

42.5
40.0

48.8

30.2

Week 0 Week 4 Week 8 Week 12 Week 16
0

10

20

30

40

50

60

70

80

90

100

Pa
tie

nt
s 

A
ch

ie
vi

ng
 P

A
SI

 1
00

 (
)

47.6
54.8

41.5 41.5

20.017.5

16.314.0

PASI 75

PASI 90

PASI 100

aOne patient each with missing response in risankizumab 18 mg and ustekinumab 45/90 mg groups, and were imputed as  
non-responders. Abbreviations:  NRI=non-responder imputation; PASI=Psoriasis Area and Severity Index.

• Patients treated with 90 mg or 180 mg of risankizumab achieved 
higher response rates across all levels of PASI improvement when 
compared with patients treated with 18 mg risankizumab (single dose) 
or ustekinumab (Figure 3).

Figure 3. Distribution of Changes in PASI Responses from 
Baseline at Weeks 12 and 16 (NRI)

W
ee

k 
12

W
ee

k 
16

PASI 100
PASI 90 - <100
PASI 75 - <90

PASI 50 - <75
PASI 25 - <50

PASI 0 - <25
Worsening

0 20 40 60 80 100

Risankizumab
180 mg (N=42)

Risankizumab 
90 mg (N=41)

Risankizumab
18 mga (N=43)

Ustekinumab
45/90 mga (N=40)

Percentage of Patients

0 20 40 60 80 100

Risankizumab
180 mg (N=42)

Risankizumab 
90 mg (N=41)

Risankizumab
18 mga (N=43)

Ustekinumab
45/90 mga (N=40)

Percentage of Patients
a. One patient each with missing response in risankizumab 18 mg and ustekinumab 45/90 mg groups, and were imputed as having 
no (0%) improvement. Abbreviations:  NRI=non-responder imputation; PASI=Psoriasis Area and Severity Index.

Figure 4. Cumulative Probability of Percent Change from 
Baseline in PASI Scores at Weeks 12 and 16 (NRI)

• The cumulative probability plot demonstrated that patients treated 
with 90 or 180 mg of risankizumab had a higher likelihood of achieving 
greater improvements from baseline in PASI score compared with 
patients treated with 18 mg risankizumab or ustekinumab (Figure 4).

 – Median values for improvement in PASI scores at week 12 were 
81.7%, 94.6%, and 98.8% in patients treated with 18 mg, 90 mg, 
and 180 mg of risankizumab, respectively, compared with 85.6% in 
ustekinumab-treated patients.

 – At week 16, median values for improvement in PASI scores were 
87.4%, 97.5%, and 100.0% in patients treated with 18 mg, 90 mg, 
and 180 mg of risankizumab, respectively, compared with 87.0% in 
ustekinumab-treated patients.

-100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40
0

10

20

30

40

50

60

70

80

90

100
Week 12

Percent Change from Baseline in PASI Score

Cu
m

ul
ati

ve
 P

ro
ba

bi
lit

y

Risankizumab 1  mga
Risankizumab  90 mg
Risankizumab 1 0 mg

Ustekinumab 45 90 mga

PA
SI

 9
0

PA
SI

 1
00

PA
SI

 5
0

PA
SI

 7
5

-100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40
0

10

20

30

40

50

60

70

80

90

100
Week 16

Percent Change from Baseline in PASI Score

Cu
m

ul
ati

ve
 P

ro
ba

bi
lit

y

PA
SI

 9
0

PA
SI

 1
00

PA
SI

 5
0

PA
SI

 7
5

PASI Response
Mean
76.0%
72.3%
93.4%
88.6%

Median
85.6%
81.7%
94.6%
98.8%

PASI Response
Mean
77.8%
79.5%
93.1%
90.3%

Median
87.0%
87.4%
97.5%

100.0%

B Strober has received honoraria or fees for serving on advisory boards and as a consultant for AbbVie, Almirall, Amgen, Boehringer Ingelheim, Celgene, Dermira, Eli Lilly, Janssen-Ortho, Leo 
Pharma, Maruho, Merck, Novartis, Pfizer, Sanofi/Regeneron, Sun Pharma, and UCB. He is a scientific director for the CORRONA-NPF Psoriasis Registry. KA Papp has received honoraria or fees for 
serving on advisory boards, as a speaker, as a consultant, grants as an investigator from AbbVie, Amgen, Astellas, Baxalta, Baxter, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Dermira, 
Eli Lilly, Forward Pharma, Galderma, Genentech, GlaxoSmithKline, Janssen, Kyowa-Hakko Kirin, Leo Pharma, MedImmune, Merck-Serono, Merck Sharp & Dohme, Novartis, Pfizer, Regeneron, 
Roche, Sanofi-Genzyme, Stiefel, Sun Pharma, Takeda, UCB, and Valeant. M Flack is a full-time employee of Boehringer Ingelheim. Y Gu, EHZ Thompson, and WC Valdecantos are full-time salaried 
employees of AbbVie and may own stock/options. Boehringer Ingelheim funded the study (NCT02054481), contributed to its design and participated in data collection. AbbVie participated in data 
analysis and interpretation of the data, and in writing, review, and approval of the publication. Medical writing support was provided by Deepa Venkitaramani, PhD, of 
AbbVie.

a. One patient each with missing response in risankizumab 18 mg and ustekinumab 45/90 mg groups, and were  
imputed as having no (0%) improvement. Abbreviations: NRI=non-responder imputation; PASI=Psoriasis Area and Severity Index.

DISCLOSURES

Presented at the Fall Clinical Dermatology Conference - 36th Anniversary • Las Vega, Nevada • October 12 – 15, 2017


	FC17PosterAbbVieStroberDistributionofImprovements.pdf