Shikha Singla, MD, on Comparative Analysis of Guidelines for PsA

Dr Singla reviews the comparative analysis she and colleagues conducted of guidelines for the diagnosis and treatment of psoriatic arthritis and how they differ between the professional societies.

Shikha Singla, MD, is an associate professor of medicine (rheumatology) at the Medical College of Wisconsin, where she serves as the medical director of the psoriatic arthritis program in Milwaukee, Wisconsin.

Psoriatic Arthritis Guidelines (ACR, EULAR, GRAPPA, BSR, PANLAR): Comparative Clinical Brief

• Psoriatic arthritis (PsA): All global guidelines (ACR, EULAR, GRAPPA, BSR, PANLAR endorse treat-to-target, but targets and timing vary. EULAR specifies 3–6 months, PANLAR requires 1-year remission before tapering, and GRAPPA emphasizes individualized, patient-centered assessment. Clinicians should integrate minimal disease activity (MDA) or DAPSA targets with shared decision-making and reassess every 12–24 weeks, incorporating comorbidities and patient-reported outcomes.
• Biologic/tsDMARD selection and sequencing: ACR favors TNF inhibitors and recommends switching to a second TNF after failure, while EULAR, BSR, GRAPPA, and PANLAR offer broader class options (TNF, IL-17, JAK). EULAR favors combination therapy; PANLAR prefers monotherapy. Lack of consensus exists on sequencing; abatacept is included but ranked lower (EULAR/BSR). IL-23 inhibitors are absent in older guidelines due to publication timing.
• Comorbidities: TNF inhibitors are preferred over IL-17 inhibitors in IBD/uveitis due to safety/efficacy concerns. Enthesitis/dactylitis recommendations vary: ACR suggests NSAIDs, TNF inhibitors, or tofacitinib in treatment-naive patients; EULAR recommends biologics after NSAID/local failure. Cost, access, and regional policy (e.g., PANLAR vs US ACR) significantly influence recommendations and implementation.

Welcome to this podcast from the Rheumatology and Arthritis Learning Network. I'm your moderator, Rebecca Mashaw. And today I'm delighted to have Dr. Shika Singla, an associate professor at the Medical College of Wisconsin who will be talking to us about the comparative analysis on guidelines for psoriatic arthritis management that she and colleagues conducted. Thank you for joining us today, Dr. Singla.

Dr Singla:

Thank you for having me, Rebecca.

RALN:

So first of all, what led you and your colleagues to do this comparison of, comparing global guidelines for treating psoriatic arthritis?

Dr Singla:

Yeah, so we are all aware of the heterogeneity of psoriatic arthritis and many different domains getting affected by the disease. This can present as a challenge for health care professionals to select the most appropriate therapy for the patients. So we thought of providing a guide to clinicians by consolidating and comparing recommendations from major rheumatology organizations to provide some global perspective of psoriatic arthritis management.

RALN:

In this comparative review, did you find that any differences in methodology like the GRADE versus expert consensus across these guidelines made any significant difference in the strength of recommendations or the direction they took?

Dr Singla:

Great question, Rebecca. There were two factors that influenced the guidelines. One was the team composition. Each organization used different multidisciplinary groups such as dermatologists, rheumatologists, and patient advocates, and some used epidemiologists as well. And the second one was the grading method, like GRADE versus Oxford evidence-based medicine. So I do not think that these differences explicitly influenced the strength or directions of the recommendations. I believe that the direction of recommendation was more influenced by the timing of publication. For example, the ACR guidelines were noted being a little older as compared to GRAPPA and EEULAR recommendations.

RALN:

And with the pace of medications, I imagine that makes a difference in which medications are being reviewed in the process as well, right?

Dr Singla:

Exactly. So IL-23s are comparatively newer class of drugs which were not included in some of the recommendations.

RALN:

While treat-to-target is pretty much universally endorsed, how do the guidelines differ in defining treatment targets, such as minimal disease activity versus DAPSA remission? And is there a way clinicians can reconcile those differences in clinical practice?

Dr Singla:

Yes, treat-to-target was universally endorsed, but there were some differences with EULAR requiring specific 3 to 6 months target, PANLAR mandating a strict 1-year remission for tapering and GRAPPA focusing on patient-centered individualized assessments. To reconcile these clinicians should blend strict evidence-based targets such as MDA and DAPSA with shared decision-making with regularly assessing patients every 12 to 24 weeks, I would say, while balancing disease activity, comorbidities, and patient reported outcomes as well.

RALN:

Can you elaborate a bit on any key divergences in first-line biologic or targeted synthetic DMARD selection, particularly between TNF inhibitors, IL-17, IL-23s, and the JAK inhibitors?

Dr Singla:

Yeah, I think the divergence is based on the timing like we discussed. The ACR favored TNF inhibitors like EULAR, BSR, GRAPPA, and PANLAR offered broader, but different preferences for TNF and IL-17 inhibitors, as well as JAK inhibitors. The key differences included that EULAR favored combination therapy, whereas PANLAR preferred monotherapy and ACR recommended switching toward second TNF over switching to a class.

RALN:

Well, I think that answers my next question, which is how do they vary in recommendations for sequencing therapy? And so it sounds like some of what you were just explaining gives some insight into that, but can you tell us a little bit more about differences in how therapies should be sequenced according to these guidelines?

Dr Singla:

There is clearly a lack of consensus on the optimal sequencing leading to different hierarchical preferences among the societies. For example, GRAPPA's broad endorsement versus ACR’s specific preference for TNF. When a biologic DMARD fails, ACR specifically favors another TNF, as I said, whereas EULAR and BSR include abatacept as an option, but rank it lower than other classes.

RALN:

To what extent do comorbidities like IBD, uveitis, metabolic syndrome, drive therapeutic selection across these guideline frameworks?

Dr Singla:

Comorbidities such as IBD and uveitis significantly dictate the selection with guidelines uniformly favoring TNF inhibitors over IL-17 inhibitors due to safety risk in IBD or reduced efficacy in uveitis. While ACR, BSR, and GRAPPA prioritized TNF inhibitors, they also recommended specialized interdisciplinary approach for managing these conditions with some guidelines advising against specific agents like IL-17 inhibitors in IBD.

RALN:

In the management of enthesitis and dactylitis, which agents are preferentially recommended across the guidelines? Did you find significant inconsistency in those and in the evidence base for them?

Dr Singla:

Yes, Rebecca. There are inconsistencies in the role of conventional DMARDs. ACR, BSR and GRAPPA, they prioritize advancing therapies while GRAPPA cautiously accepts methotrexate for dactylitis and enthesitis. Particularly for enthesitis, ACR recommends NSAIDs, TNFs, or tofacitinib in treatment-naive patients. And EULAR suggests imaging and recommends biologic DMARDs for failure of NSAIDs or local injections. And BSR supports any biologic or targeted synthetic DMARDs after conventional DMARD failure, while GRAPPA prefers IL-17s and TNF inhibitors.

RALN:

How do regional factors such as drug availability, cost considerations, regulatory approvals, shape these variations among the guidelines?

Dr Singla:

Good question. While scientific evidence is similar globally, the recommendations differ due to focus on expert consensus, cost-effectiveness, or regional accessibility. For example, PANLAR focuses on local realities, including high cost and limited access, often prioritizing affordable option first. In USA, ACR guidelines, they're tailored towards navigating complex restricted insurance formularies and high drug-related costs. And GRAPPA tends to provide comprehensive guidance, often featuring strong input from dermatologists, but may struggle with rapid updates in local availability.

RALN:

Did your analysis look at meaningful differences in the guidances on tapering or de-escalating medications among patients who have achieved sustained remission or low disease activity?

Dr Singla:

There were minimum differences regarding timing and strictness or approach and details of de-escalation, such as PANLAR is more conservative than others, advising that at least 1 year of remission must be achieved before tapering is considered in clinical practice. GRAPPA provides the most detailed guidance compared to EULAR and BSR, advocating for specific methods like interval extension, dose reduction, and individualized risk assessment. There were also some differences in the focus. While EULAR and BSR support tapering, BSR specifically emphasized shared decision-making and specialist consultation.

RALN:

The emergence of newer targets like TYK2 inhibition or the novel IL-23 pathway agents—how do you anticipate future updates are going to shift current treatment algorithms?

Dr Singla:

That's a great question. With the emergence of newer targets, shifts of treatment algorithms will be from a TNF-first approach towards more tailored mechanism-driven strategies. The key updates are likely to emphasize earlier intervention with these agents, positioning them as premier options for patients with significant skin involvement, or those who prefer oral agents over injectable therapies. There is a shift from broad JAKs to selective TYK2 inhibition option, and also a shift towards precision medicine, which is tailored therapies and selection based on particular domains.

RALN:

So based on your findings, do you envision movement toward more global harmonization of these PSA guidelines?

Dr Singla:

We all wish that, right? There is an unmet need to reduce redundant evidence synthesis and to standardize care in a rapidly evolving therapeutic landscape. Most international guidelines already align on domain-based treatment and treat-to-target strategies. There is hope that there are going to be some hybrid framework model and global collaborations. We've already seen that organizations like GRAPPA and ILAR, International League of Association of Rheumatology have actively created recommendations that adapt high-resource guidelines for resource-poor settings.

RALN:

Very good. Well, this has been very interesting, and we really appreciate your insights into this, and hopefully we will see more of that harmonization so that clinicians can be confident that they're getting the best advice, and hopefully insurers will pay attention to that as well.

Dr Singla:

Agreed.

RALN:

Thank you very much for your time today.

Dr Singla:

Thank you for having me.