GRAPPA is an amazing network of people interested in psoriasis and PsA. Through involvement, you can share ideas, collaborate on research, and lead projects aiming to improve the lives of people living with psoriatic disease.


About Us

Originally inspired by the Assessment in Ankylosing Spondylitis Working Group (ASAS), GRAPPA was formed in 2003. GRAPPA has pulled together many different groups, including preeminent researchers and thought-leaders in psoriatic arthritis (PsA) and psoriasis (PsO). In 2015 a team of Patient Research Partners was added to round out our perspective.  The idea was to form a consortium of rheumatologists, dermatologists, radiologists, epidemiologists, patient representatives and others who would like to contribute to the field of PsA. At the inaugural meeting in 2003, a consensus exercise started the group toward prioritizing domains of inquiry in PsA and PsO. Subsequent annual meetings have focused on identifying and initiating research projects, advancing standardized criteria for psoriatic arthritis registries, and developing treatment guidelines for PsA. GRAPPA is a 501(c)3 nonprofit organization with offices in Seattle, WA and members from around the world.

Today, more than 1,000 thought-leaders participate in GRAPPA including rheumatologists, dermatologists, radiologists, geneticists, methodologists, epidemiologists, patient research partners, and biopharmaceutical industry representatives. Approximately 75 percent of our members live and work outside North America; creating a truly international effort.

Our Goals

GRAPPA is focused on research and treatment of psoriasis and psoriatic arthritis.

Our mission is to share information, facilitate networking among medical disciplines, and to enhance research, diagnosis, and treatment.

  • Provide a forum for networking and communication between international researchers in rheumatology and dermatology, industry, patient service leagues, and regulatory agencies
  • Provide the opportunity for in-person meetings and online communication to share knowledge, research findings, and develop or conduct collaborative research, education and other projects
  • Develop and validate a criteria set for the definition of psoriatic arthritis (PsA)
  • Review, develop and validate effective and feasible outcome measures for the assessment of PsA and psoriasis (PsO)
  • Promote the development of national and international collaborative registries of PsA and PsO patients to standardize the data being obtained and learn more about the natural history of the disease as well as its genetic underpinnings
  • Work closely with representatives of patient service leagues to promote public education and awareness of PsA and PsO
  • Work closely with representatives of member biopharmaceutical companies to promote and conduct research on effective therapies for PsA and PsO
  • Reach out to representatives of regulatory agencies to establish appropriate guidelines for regulatory approval of new therapies
  • Work with other professional organizations, such as the American College of Rheumatology, American Academy of Dermatology, and OMERACT to promote knowledge of research about PsA and PsO within the context of those disciplines
  • Develop and maintain current Treatment Guidelines for psoriatic arthritis

Our Accomplishments

Publications authored by GRAPPA members every year since 2005


Publications authored by GRAPPA members every year since 2005


Development of evidence-based review of psoriatic arthritis (PsA) treatments published Spring 2006 and publication of refreshed Treatment Recommendations in 2016


Participation as the PsA working group at every OMERACT meeting since 2004


Meetings held adjacent to AAD, EULAR and ACR (2004 to the present)


GRAPPA Annual Meetings at various locations around the world in 2005 to the present. See the Events tab for information on the latest Annual Meeting. A supplement covering the Annual Meeting activities has been published every year since 2006 in the Journal of Rheumatology


More than a dozen committees are pursuing a variety of research projects


Response Measure Project was completed in 2014 after participation by more than 40 centers worldwide


GRAPPA has produced video training modules to learn exams such as the PASI, NAPSI, PSSI, PGA, Palmar-Plantar, Axial Spine and others. These are available through our partner ePharma Solutions. Contact [email protected] for more information on accessing these online trainings


GRAPPA also operates in the EU! The mission of GRAPPA EU is to further the work of GRAPPA with a specific focus on participating in research projects relating to psoriasis and psoriatic arthritis in the European Union.

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