IPC’s Disease Severity Working Group has refined the criteria for psoriasis disease severity based on the latest clinical trials and observational data. These tables demonstrate where and how our new classification is already being applied, helping to build momentum for broader adoption:
Additional tables identify published treatment targets to assist clinicians in identifying transition points from topical to systemic therapy.
Designed as a transparent, citable resource, these tables showcase real-world implementation of IPC’s new severity criteria, both in peer-reviewed studies worldwide and within official practice guidelines, to provide compelling evidence that encourages others to follow suit. Use the quick links below to jump directly to each table, or scroll for the full dataset.
| Study | Drug and Study Population | Results | Reference |
|---|---|---|---|
| IXORA-Q | Ixekizumab in patients with moderate to severe genital psoriasis | 73% of patients on ixekizumab reached SPGA 0 or 1 vs 8% of patients on placebo at week 16 | Ryan C, Menter A, Guenter , et al. Efficacy and safety of ixekizumab in a randomized, double-blinded, placebo-controlled phase IIIb study of patients with moderate-to-severe genital psoriasis Br J Dermatol. 2018;179:844-852. doi: 10.1111/bjd.16736. |
| DISCREET | Apremilast in patients with moderate to severe genital psoriasis | 39.6% of patients on apremilast reached a Modified sPGA-G 0 or 1 and a reduction ≥2 points of Modified sPGA-G vs 19.5% of patients on placebo at week 16 | Merola JF, ParishLC, Guenter L, et al. Efficacy and safety of apremilast in patients with moderate-to-severe genital psoriasis: Results from DISCREET, a phase 3 randomized, double-blind, placebo-controlled trial J Am Acad Dermatol. 2024;90:485-493. doi: 10.1016/j.jaad.2023.10.020 |
| G-PLUS | Guselkumab in nonpustular palmolantar psoriasis | 35.9% of patients on guselkumab reached ppPASI75 vs 28.2% of patients on placebo at week 16 | Passeron T, Carrascosa JM, Warren RB, et al. A Phase IIIb, Multicentre, Interventional, Randomised Placebo-Controlled Clinical Trial Investigating the Efficacy and Safety of Guselkumab for the Treatment of Nonpustular Palmoplantar Psoriasis (G-PLUS). Dermatologic Therapy Volume 2023, Article ID 9967747 |
| REACH | Adalimumab in patients with moderate to chronic plaque psoriasis of hands and feet | 31% of patients on adalimumab reached hfPGA75 vs 4% of patients on placebo at week 16 | Leonardo C, Langley RG, Papp K, et al Adalimumab for treatment of moderate to severe chronic plaque psoriasis of the hands and feet: efficacy and safety results from REACH, a randomized, placebo-controlled, double-blind trial. Arch Dermatol. 2011;147:429-36 |
| GESTURE | Secukinumab in palmoplantar psoriasis | 33.3% of patients on secukinumab 300mg reached ppIGA 0/1 and a reduction of ≥2 points in ppIGA vs 22.1% of patients on secukinumab 150mg vs 1.5% of patients on placebo at week 16 | Gottlieb A, Sullivan J, van Doorn M, et al. Secukinumab shows significant efficacy in palmoplantar psoriasis: Results from GESTURE, a randomized controlled trial. J Am Acad Dermatol 2017 ;76:70-80. doi: 10.1016/j.jaad.2016.07.058 |
| IMMprint | Risankizumab in patients with moderate-to-severe plaque psoriasis with non-pustular palmoplantar involvement | 33.3% of patients on Risankizumab 150 mg reached ppIGA 0/1 and a reduction of ≥2 points in ppIGA vs 16.1% of patients on placebo at week 16 | Lebwohl M, Bukhalo M, Stein Gold L, et al. randomized phase 3b study evaluating the safety and efficacy of risankizumab in adult patients with moderate-to- severe plaque psoriasis with non- pustular palmoplantar involvement J Am Acad Dermatol 2024;91:1150-7 |
| STYLE | Apremilast in patients with moderate to severe plaque psoriasis of the scalp | 43% of patients on apremilast reached ScPGA score 0 or 1 with ≥2-point reduction from baseline vs 13,7% of patients on placebo at week 16 | Van Voorhees AS, SteinGold L, Lebwohl M, et al. Efficacy and safety of apremilast in patients with moderate to severe plaque psoriasis of the scalp: Results of a phase 3b, multicenter, randomized, placebo-controlled, double-blind study. J Am Acad Dermatol. 2020 ;83:96-103. |
| Secukinumab in patients with scalp psoriasis | Secukinumab in patients with moderate to severe scalp psoriasis | 57% of patients on secukinumab reached IGA-scalp score of 0 or 1 vs 6% of patients on placebo on placebo at Week 12 | Bagel J, Calis Duffin K, Moore A, et al. The effect of secukinumab on moderate-to-severe scalp psoriasis: Results of a 24-week, randomized, double-blind, placebo-controlled phase 3b study. J Am Acad Dermatol 2017;77:667-74. |
| PSORIATYK SCALP | Deucravacitinib in patients with scalp psoriasis | 57.6% of patients reached sPGA 0 or 1 in vs 57,6% vs 5,3% on placebo at week 24. | Lebwohl M, et al. EADV 2024, FC04.07 |
| SPECTREM | Guselkumab in patients with low BSA and involvement of high impact sites | 74% of patients on Guselkumab reached IGA score of 0 or 1 vs 12% in the placebo group at week16 Site-specific IGA/PGA 0/1 response rates for guselkumab versus placebo were: scalp, 75.0% (114/152) versus 14.5% (11/76); face, 87.8% (79/90) versus 28.6% (12/42); genital, 78.0% (64/82) versus 37.5% (15/40); and intertriginous, 86.5% (96/111) versus 28.8% (15/52). | Presented by L Stein Gold at Fall Clinical Dermatology Conference; October 24-27, 2024; Wynn Las Vegas, NV, USA Presented at the 2025 Fall Clinical Dermatology Conference; October 23-26, 2025; Las Vegas, NV, USA. |
| GULLIVER | Guselkumab in patients with facial (FP) and genital psoriasis (GP) | .3% of FP patients achieving a facial sPGA score of 0 or 1 at Week 12; 76.5% of GP patients achieving a facial sPGA score of 0 (clear) or 1 (almost clear) at Week 12 | Bonifati C, Lembo S, Richetta AG, et al. Effectiveness of guselkumab in patients with facial and/or genital psoriasis: Interim analysis results at Week 12 from the GULLIVER study. J Eur Acad Dermatol Venereol. 2025;39(Suppl 1):7-14. |
| ICONIC-TOTAL | Icotrokinra in psoriasis on high-impact sites (scalp, genitals, hands, and feet) | The proportions of icotrokinra-treated and placebo-treated participants achieving absence/clear or minimal/almost clear high-impact site psoriasis were : scalp 65.9% vs10.6%); genitalia 76.5% vs 21.4%; and hand and foot 41.7% vs 26.1%. | Gooderham M, Lain E, Bissonnette R, Huang YH, Lynde CW, Hoffmann M, Song EJ, Weirich O, Ceitlin RHG, Rubens JH, DeLozier AM, Ota T, Hsu MC, Li S, DeKlotz CMC, Nunes F, Warren RB. Targeted Oral Peptide Icotrokinra for Psoriasis Involving High-Impact Sites. NEJM Evid. 2025 Nov 5:EVIDoa2500155. doi: 10.1056/EVIDoa2500155. Epub ahead of print. PMID: 41191932. |
| 1-year ICONIC TOTAL | Icotrokinra in patients with psoriasis on the genitals, hands, feet, scalp, and nails. | Icotrokinra demonstrated high and durable rates of psoriasis clearance across high impact sites, with a favourable safety profile , through 1 year. | Warren RB, Gooderham M, Lain E, Bissonnette R, Huang Y-H, Ringuet J, et al. Durability of response to icotrokinra for high-impact site psoriasis: 1-year ICONIC-TOTAL findings. J Eur Acad Dermatol Venereol. 2026; 00: 1–13. https://doi.org/10.1111/jdv.70471 |
Table last updated August 5, 2026
hfPGA: Global Assessment of Hands and/or Feet; ppPASI: Palmoplantar Psoriasis Area and sSeverity Index; ppIGA: Palmoplantar Investigator’s Global Assessment; sPGA: Static Physician Global Assessment; IGA: Investigator Global Assessment; ScPGA: Scalp Physician Global Assessment; ppIGA: Palmoplantar Investigator’s Global Assessment; ppPASI: Palmoplantar Psoriasis Area and Severity Index; Modified sPGA-G: Modified Static Physician Global Assessment of Genitalia
Table last updated September 15, 2026.
Striving for clear skin has a major impact on improving quality of life (1, 2).
Outcome Measure | Source | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Region Country | % PASI | PASI (res) | BSA (res) | DLQI | PGA | National Guideline | Expert Group | Time Frame | Ref |
| Africa/Eastern Mediterranean | |||||||||
| Saudi Arabia | ≤90 | ≤3 | 0/1 | X | 17 | ||||
| Europe | |||||||||
| Denmark | ≤3 | DDS | 16 | ||||||
| Europe | ≤90 | ≤2 | ≤2 | 0/1 | EDF | 8, 25 | |||
| France | ≤90 | ≤3 | 0/1 | FSD | 11 | ||||
| Germany# | ≤90 | ≤3 | ≤2 | DDG | 20 | ||||
| Italy | ≤90 | ≤3 | X | 3–4 months | 10 | ||||
| Poland | ≤90 | PDS | 14 | ||||||
| Portugal | ≤90 | ≤2 | SPVD | 12 | |||||
| Spain | ≤90 | ≤3-5 | minimal | 0/1 | 0/1 | SADV | 13 | ||
| Switzerland* | ≤75 | ≤5 | SSDV | 24 | |||||
| United Kingdom | ≤2 | 0/1 | BAD | 5 | |||||
| Latin America/Caribbean | |||||||||
| Argentina@ | ≤90 | ≤3 | 0/1 | 0/1 | SAD | 22 | |||
| Brasil@ | ≤90-100 | ≤3 | ≤3 | 0/1 | 0/1 | SBD | 21 | ||
| Colombia | ≤90 | ≤3 | ACDD | 23 | |||||
| Colombia | ≤75! | ≤5! | ACDD | 23 | |||||
| North America | |||||||||
| Canada | ≤3 | ≤1 | 0/1 | X | 6 | ||||
| Canada | ≤75 | CDA | 7 | ||||||
| United States | ≤1 | NPF | 3 months | 3, 4 | |||||
| Southeast Asia/Western Pacific | |||||||||
| Australia | ≤90 | ≤3 | 0/1 | ACD | 9 | ||||
| China | ≤90-100 | 0/1 | SCD | 19 | |||||
| Japan | ≤90 | ≤2 | 0/1 | JDA | 15 | ||||
| Malaysia | ≤3 | ≤5 | JDA | 18 | |||||
Table last updated August 14, 2025
Abbreviations: PASI: Psoriasis Area and Severity Index; PASI res: residual PASI; BSA: Body Surface Area; BSA res: residual BSA; DLQI: Dermatology Life Quality Index; PGA: Physician’s Global Assessment; DDS Danish Dermatological Association; EDF: European Dermatology Forum; FSD: Frech Society of Dermatology; DDG: Deutsche Dermatologische Gesellschaft; PDS: Polish Dermatological Society; SPVD: Portuguese Society of Dermatology and Venereology; SADV: Spanish Academy of Dermatology and Venereology; SSDV: Swiss Society of Dermatology and Venereology; BAD: British Association of Dermatologists; SAD: Sociedad Argentina de Dermatologia; SBD: Sociedade Brasileira de Dermatologia; ACDD: Asociación Colombiana de Dermatología y Cirugía Dermatológica; CDA: Canadian Dermatology Association; NPF: National Psoriasis Foundation; ACD: Australian College of Dermatologists; SCD: Chinese Society of Dermatology; JDA: Japanese Dermatological Association; DSM: Dermatologic Society of Malaysia
#There is an ongoing discussion within DDG.
*A potential future goal of reaching PASI90 within 52 weeks after starting therapy seems achievable with newer therapies.
@PASI 75 can be accepted as minimum treatment maintenance index if patient has no negative impact in quality of life.
!Combination required.
All guidelines emphasize topical failure as a key indicator for systemic escalation, but exact definitions vary:
| Country | Guidance (Year) | When to Switch to Systemic Treatment | Ref. |
|---|---|---|---|
| United States | AAD-NPF Guidelines (2018–2021) | Systemic therapy indicated if >5–10% BSA involved or if topical treatments fail to achieve control. Also if psoriasis affects high-impact sites (hands, face, genitals, etc.) or causes significant life impact. | 1 |
| United Kingdom | NICE Guideline (2012, updated) | If topicals are inadequate and disease has significant impact. E.g. >10% BSA or PASI >10, or localized severe sites (nails, scalp, etc. with functional impairment), or rapid relapse after other therapy. | 2,3 |
| Canada | CDA Guidelines (2009 + 2016 addendum) | If topical agents no longer suffice to control disease. | 4 |
| Europe | EuroGuiDerm (2025, updated) | Failure of topical treatments. | 5 |
| France | SFD Psoriasis Guidelines (2019) | Systemic therapy (incl. phototherapy) indicated if >10% BSA or PASI >10 or DLQI >10, or if significant physical/psychological impact, or if localized disease not controlled by topicals (e.g. severe nail, scalp, palmoplantar or genital psoriasis). | 6 |
| Denmark | DDS guidelines (2023) | Insufficient efficacy of topical treatment in adults is defined as insufficient efficacy of daily use of a class 3-4 topical steroid or a combination of topical steroid and calcipotriol for 4 weeks, possibly extended to 8 weeks after assessment. | 7 |
| Australia | ACD Guidelines (2024) | Psoriasis worsens during topical treatments. | 8 |
Table last updated August 14, 2025
Abbreviations: AAD: American Academy of Dermatology; NICE: National Institute for Health and Care Excellence; DLQI: Dermatology Quality of Life Index; SFD: Société Française de Dermatologie; CDA: Canadian Dermatological Association; DDS: Danish Dermatological Association; NPF:National Psoriasis association; ACD: Australasian College of Dermatologists
IPC Jr. Councilor Towhida Noor reviews the psoriasis pipeline: selective TYK2 inhibitors, long-acting IL-17 and IL-23 biologics, and IL-36 blockade in GPP.
IPC Board Member and Treasurer Joel Gelfand, MD, MSCE, is the editor of a new textbook, Psoriasis: An Expert Global Perspective, now available for preorder from Elsevier. He worked with associate editors IPC President Bruce Strober, MD, PhD; IPC Vice President/President-Elect Claudia de la Cruz, MD; and IPC Chief Medical Officer Peter van de Kerkhof, MD, PhD. Nearly 50 authors from 20 countries contributed 30 chapters covering psoriasis from its earliest descriptions through genetics, immunology, and current therapies, with clinical images of psoriasis across diverse skin tones. All royalties support IPC.
PRE-ORDER YOUR COPY
In this video, IPC Councilor Rodrigo Garcia Salinas, MD, a rheumatologist from Argentina, explains how to recognize psoriatic arthritis early, including why joint pain, how long a patient has had psoriasis, and family history can matter more than skin severity alone. He also reviews how imaging helps catch early disease and how to choose treatment based on each patient’s joint, spine, and skin involvement.
IPC President Bruce Strober reviews the link between psoriasis and metabolic disease, drawing on findings from IPC’s recent paper in the Journal of the American Academy of Dermatology (JAAD). He translates this growing body of evidence into five concrete priorities from the 2025 IPC Think Tank for improving cardiometabolic screening and care.
