The agenda for this year’s Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) annual meeting included sessions on juvenile psoriatic arthritis (PsA), the microbiome in psoriasis and PsA, and setting up longitudinal cohort studies. There was also a workshop to define the clinical fit and feasibility of PsA outcome measures for clinical trials and updates on several GRAPPA-associated projects.

The meeting, held July 13-15 in Amsterdam, opened with the annual trainee session. This year’s trainee session attracted more than 40 abstracts, of which 6 were selected for oral presentations on a variety of topics including outcome measure assessment, imaging, the microbiome in PsA, and T-cell subsets in synovial fluid.

The juvenile PsA session highlighted the similarities and differences between juvenile and adult PsA. For example, nearly half of children develop the arthritis prior to the skin symptoms, as opposed to adults where the vast majority develop psoriasis first.

The jPsA session also emphasized the need for efforts to better define this disease entity and to study outcomes related to it. The current International League of Associations for Rheumatology criteria for juvenile idiopathic arthritis split jPsA into other subgroups (for example, enthesitis-associated arthritis, undifferentiated arthritis, etc).

Three investigators – Matt Stoll, MD, PhD, Devy Zisman, MD, and Elizabeth Mellins, MD – also presented studies of the epidemiology of jPsA.

Among the most intriguing sessions at the GRAPPA meeting was a series of three talks by Jose Scher, MD, Hok Bing Thio, MD, PhD, and Dirk Elewaut, PhD, that introduced the audience to the complexity of the micro-organisms that call the human host “home” and the potential role in the development of inflammatory conditions, in particular psoriasis and PsA. These talks touched on the potential uses of the microbiome of the gut, skin, and oral mucosa in predicting therapy response and modulating the immune system.

Dafna Gladman, MD, led a session on “how to set up a cohort.” In this session, speakers provided a road map for setting up a longitudinal cohort and discussed opportunities and challenges along the way. This session provided a foundation for a meeting that followed the annual meeting, the GRAPPA Research Collaborative Network meeting (held July 15-16). The RCN meeting aimed to develop a plan for a GRAPPA research network supporting collaborative research to identify biomarkers and outcomes in psoriasis and PsA. Speakers/panelists from academics and industry kicked off the meeting with a discussion of prior experiences in establishing international cohort studies. Subsequent sessions presented individual aspects of beginning a longitudinal cohort study for biomarkers, including methods for sample collection, regulatory processes, and data collected at potential sites; capturing and harmonizing clinical data for such studies; and policies for publication of RCN studies.

This year’s workshop was focused on the GRAPPA-Outcome Measures in Rheumatology (OMERACT) working group’s plan to develop a Core Outcome Measure Set, a collection of outcome measurement instruments to be used in randomized, controlled trials (RCTs) for PsA. During the plenary session, the team presented a process for the group to evaluate instruments, including assessment of match to the domain or concept of interest, feasibility, construct validity, and discrimination (including reliability and the ability to distinguish between two groups such as responders and nonresponders). Breakout groups then discussed one of the six tools being considered and voted on match to the domain of interest and feasibility for RCTs.

In a skin session, ongoing efforts to standardize and simplify the measurement of skin psoriasis in both the clinic and RCTs were presented. While the Psoriasis Area and Severity Index (PASI) is the current standard for measuring psoriasis severity and response to therapy in RCTs, the PASI is challenging for use in clinical practice. Joseph Merola, MD, presented data to support the use of the psoriasis Physician Global Assessment (PGA) x body surface area (BSA), a simpler measure than the PASI, as a potential substitute for the PASI. Updates from the International Dermatology Outcome Measures board included reporting of the psoriasis core domain set and a summary of the PsA symptoms working group’s efforts to identify patient-reported outcomes to identify and measure PsA among patients enrolled in psoriasis RCTs. April Armstrong, MD, discussed the National Psoriasis Foundation’s efforts to develop treat-to-target goals for psoriasis. Finally, Laura Coates, MBChB, PhD, presented a report on her efforts to examine a variety of psoriasis cut points for minimal disease activity and very low disease activity outcomes.

Dr. Ogdie is director of the Penn Psoriatic Arthritis Clinic at the University of Pennsylvania, Philadelphia, and is a member of the GRAPPA Steering Committee.

Psoriasis, psoriatic arthritis research makes headway at GRAPPA meeting