Polymyalgia rheumatica and giant cell arteritis induced by immune checkpoint inhibitors: A systematic literature review highlighting differences from the idiopathic forms.

INTRODUCTION: An altered immune tolerance disturbed by immune checkpoint inhibitors (ICIs) may contribute to new-onset polymyalgia rheumatica (PMR) and giant cell arteritis (GCA). This systematic literature review (SLR) examines the characteristics of PMR and GCA-like syndromes following anticancer treatment with ICIs, summarizing their demographic, clinical and treatment-related features to provide insights whether they differ from the idiopathic forms. METHODS: The SLR was conducted in Medline and EMBASE databases from inception to July 2024, and in the EULAR/ACR abstract database (2021-2023). ICI-induced PMR and GCA syndromes were compared to the primary forms of the diseases using data from studies that included both groups as comparators. For manuscripts lacking direct comparisons, we summarized the main findings and discussed the differences using systematic reviews or large observational studies on the primary forms. RESULTS: From 1237 screened abstracts, 46 met the inclusion criteria, involving 358 patients (314 with ICI-PMR and 44 with ICI-GCA). ICI-PMR had an estimated pooled prevalence of 0.1% [95% CI: 0.07%, 0.14%] among ICI recipients and 15.9% [95% CI: 12.6%, 19.9%] among patients experiencing rheumatic immune-related adverse events. Patients with ICI-PMR had a male-to-female ratio of 1.7:1 and a mean age of 71 ± 4 years. Most cases were associated with PD1/PDL1 blockers (87%). Clinical features included inflammatory pain in the girdles (100%), though pelvic girdle involvement was under-reported in some cases (3/28 studies). Peripheral arthritis was present in 35% of patients. Laboratory tests showed normal or slightly elevated inflammatory markers in 26% of cases. Glucocorticoids (GCs) led to symptom improvement in 84% of cases although 20% required immunosuppressive treatment and 14% experienced relapses. ICI-GCA had a prevalence of 0.06% among ICI recipients, with equal gender distribution and a mean age of 71 ± 5 years. Most patients received anti-PD1/PDL1 blockers (57%). Clinical manifestations included cephalic symptoms (75%), permanent visual loss (23%) and symptoms related to large-vessel involvement (54%). High-dose GCs were effective, with 96% achieving remission, though 17% experienced relapses. CONCLUSIONS: ICI-induced PMR and GCA may have distinct clinical profiles compared to idiopathic forms, with potentially milder symptoms and better treatment responses. Further studies are needed to confirm these findings and better understand the long-term outcomes and pathophysiology of these conditions.

The pipeline of immunomodulatory therapies in polymyalgia rheumatica and giant cell arteritis: A systematic review of clinical trials.

INTRODUCTION: The objective of this systematic review was to provide an overview of current developments and potentially available therapeutic options for polymyalgia rheumatic (PMR) and giant cell arteritis (GCA), in the coming years. METHODS: We conducted a systematic review of 17 national and international clinical trial databases for all disease-modifying anti-rheumatic drugs (DMARDs) for PMR and GCA that are already marketed, in clinical development or withdrawn. The search was performed on January 2024, with the keywords "polymyalgia rheumatica" and "giant cell arteritis". For each molecule, we only considered the study at the most advanced stage of clinical development. RESULTS: For PMR, a total of 15 DMARDs were identified: 2 conventional synthetic DMARDs (csDMARDs), 11 biologic DMARDs (bDMARDs) and 2 targeted synthetic DMARDs (tsDMARDs). For GCA, 18 DMARDs were identified: 2 csDMARDs, 14 bDMARDs and 2 tsDMARDs. Currently, there are only 2 approved corticosteroid-sparing therapies in these diseases, which both target the IL-6 signaling pathway, namely tocilizumab in GCA and sarilumab in PMR. Most of the molecules in current development are repurposed from from other conditions and clinical research in PMR/GCA seems to be mostly driven by the potential to repurpose existing treatments rather than by translational research. CONCLUSION: This systematic review identified 23 DMARDs evaluated for PMR and GCA: 3 csDMARDs, 17 bDMARDs and 3 tsDMARDs. Several promising treatments are likely to be marketed in the coming years.

[Polymyalgia rheumatica: What's new?] / Polymyalgia rheumatica ­ Was gibt es Neues?

Currently, only 25% of all polymyalgia rheumatica (PMR) patients are referred to specialists. An expert committee has recently recommended confirmation of diagnosis by specialist care. This can help to avoid misdiagnoses and hospital stays and can result in lower glucocorticoid doses.Using ultrasound, magnetic resonance imagining (MRI), or positron emission tomography-computed tomography (PET-CT), typical periarticular inflammatory changes are observed, especially in the shoulder and pelvic girdle area. However, for clinical use, ultrasound is usually sufficient.In 20-25% of newly diagnosed PMR patients without symptoms of giant cell arteritis (GCA), GCA can be detected through vascular ultrasound. These patients require higher glucocorticoid doses in analogy to GCA therapy. There is growing awareness of a joint GCA-PMR spectrum disease.Glucocorticoids remain the primary treatment. The interleukin-6 inhibitor Sarilumab has recently been approved in the USA for patients with recurrent PMR. Studies have also demonstrated the effectiveness of Tocilizumab in PMR.

What Is Polymyalgia Rheumatica?

This JAMA Patient Page describes polymyalgia rheumatica and its signs and symptoms, diagnosis, and treatment.

Polymyalgia rheumatica is a risk factor for more recalcitrant disease in giant cell arteritis: A retrospective cohort study.

OBJECTIVES: To evaluate differences in presentation and outcome of giant cell arteritis (GCA) patients with and without polymyalgia rheumatica (PMR) symptoms. METHODS: Consecutive patients diagnosed with GCA between 2000 and 2020 and followed for ≥12 months at the University Hospitals Leuven (Belgium), were included retrospectively. RESULTS: We included 398 GCA patients, of which 181 (45%) with PMR symptoms. Patients with PMR symptoms had a longer symptom duration (11 vs 6 weeks, p < 0.001). They less frequently reported fever (19% vs 28%, p = 0.030) and fatigue (52% vs 64%, p = 0.015) and tended to have less permanent vision loss (12% vs 19%, p = 0.052). There was no difference in the cumulative oral GC dose at 2 years (4.4 vs 4.3 g methylprednisolone, p = 0.571). However, those with PMR symptoms were treated with higher GC doses during subsequent follow-up (p < 0.05 from 38 months after diagnosis) and had a lower probability of stopping GC (62% vs 71%, HR 0.74 [95%CI 0.58-0.94], p = 0.018) with a longer median duration of GC treatment (29 vs 23 months, p = 0.021). In addition, presence of PMR symptoms was associated with an increased risk of relapse (64% vs 51%, HR 1.38 [95%CI 1.06-1.79], p = 0.017) with a higher number of relapses (1.47 [95%CI 1.30-1.65] vs 1.16 relapses [95%CI 1.02-1.31], p = 0.007). Patients with PMR symptoms less frequently developed thoracic aortic aneurysms during follow-up (3% vs 11%, p = 0.005). CONCLUSION: GCA patients with PMR symptoms had more recalcitrant disease with a higher risk of relapse and longer duration of GC treatment with need for higher GC doses.

ANCA-associated vasculitis with muscle involvement mimicking polymyalgia rheumatica.

We report a case of a woman in her early 80s with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis presented as myalgia mimicking polymyalgia rheumatica (PMR). She had positive results for the Neer and Hawkins-Kennedy impingement tests, and a normal serum creatine kinase (CK) concentration. At first, we suspected PMR; however, the patient did not strictly meet the classification criteria. Electromyography revealed an abnormal myogenic pattern, and muscle MRI revealed intramuscular and fascial hyperintensity. Moreover, chest CT revealed interstitial lung disease, and test results for ANCAs were positive. We diagnosed the patient with ANCA-associated vasculitis based on the criteria and treated her with corticosteroids and rituximab. Thus, ANCA-associated vasculitis can cause muscle involvement without elevation of the CK concentration and mimic PMR.

Investigational agents for polymyalgia rheumatica treatment: assessing the critical needs for future development.

INTRODUCTION: Polymyalgia rheumatica (PMR) is an inflammatory rheumatic disorder characterized by pain and stiffness in the shoulder and pelvic girdles, constitutional symptoms, and elevated acute-phase reactants. Glucocorticoids (GCs) remain the first-choice treatment for PMR, but relapses are common. Identification of steroid-sparing agents is therefore of utmost importance. AREAS COVERED: The efficacy of conventional immunosuppressive drugs is controversial. The use of interleukin (IL)-6 receptor inhibitors proved to be effective and safe in treating PMR patients. Currently, there are 12 ongoing clinical trials exploring potential treatments such as leflunomide, low-dose IL-2, rituximab, abatacept, secukinumab, Janus kinase inhibitors, and selective inhibitors like SPI-62 and ABBV 154. EXPERT OPINION: The high efficacy of IL-6 R receptor inhibitors as well as the numerous drug trials currently recruiting suggest that several therapeutic options will be available in the near future. Accurate diagnosis and early stratification of PMR patients according to the giant cell arteritis-PMR Spectrum Disease 'GPSD' and potential risk factors for relapsing disease or GC-related adverse events are crucial to identify patients who would benefit most from GC-sparing agents. The development of internationally accepted definitions for remission and relapse is urgently needed. Early referral strategies to specialist settings would improve disease stratification and personalized treatment.

Polymyalgia rheumatica shows metabolomic alterations that are further altered by glucocorticoid treatment: Identification of metabolic correlates of fatigue.

OBJECTIVE: In polymyalgia rheumatica (PMR), glucocorticoids (GCs) relieve pain and stiffness, but fatigue may persist. We aimed to explore the effect of disease, GCs and PMR symptoms in the metabolite signatures of peripheral blood from patients with PMR or the related disease, giant cell arteritis (GCA). METHODS: Nuclear magnetic resonance spectroscopy was performed on serum from 40 patients with untreated PMR, 84 with new-onset confirmed GCA, and 53 with suspected GCA who later were clinically confirmed non-GCA, and 39 age-matched controls. Further samples from PMR patients were taken one and six months into glucocorticoid therapy to explore relationship of metabolites to persistent fatigue. 100 metabolites were identified using Chenomx and statistical analysis performed in SIMCA-P to examine the relationship between metabolic profiles and, disease, GC treatment or symptoms. RESULTS: The metabolite signature of patients with PMR and GCA differed from that of age-matched non-inflammatory controls (R2 > 0.7). There was a smaller separation between patients with clinically confirmed GCA and those with suspected GCA who later were clinically confirmed non-GCA (R2 = 0.135). In PMR, metabolite signatures were further altered with glucocorticoid treatment (R2 = 0.42) but did not return to that seen in controls. Metabolites correlated with CRP, pain, stiffness, and fatigue (R2 ≥ 0.39). CRP, pain, and stiffness declined with treatment and were associated with 3-hydroxybutyrate and acetoacetate, but fatigue did not. Metabolites differentiated patients with high and low fatigue both before and after treatment (R2 > 0.9). Low serum glutamine was predictive of high fatigue at both time points (0.79-fold change). CONCLUSION: PMR and GCA alter the metabolite signature. In PMR, this is further altered by glucocorticoid therapy. Treatment-induced metabolite changes were linked to measures of inflammation (CRP, pain and stiffness), but not to fatigue. Furthermore, metabolite signatures distinguished patients with high or low fatigue.

Recommendations of the French Society of Rheumatology for the management in current practice of patients with polymyalgia rheumatica.

OBJECTIVE: To develop recommendations for the routine management of patients with polymyalgia rheumatica (PMR). METHODS: Following standard procedures, a systematic review of the literature by five supervised junior rheumatologists, based on the questions selected by the steering committee (5 senior rheumatologists), was used as the basis for working meetings, followed by a one-day plenary meeting with the working group (15 members), leading to the development of the wording and determination of the strength of the recommendations and the level of agreement of the experts. RESULTS: Five general principles and 19 recommendations were drawn up. Three recommendations relate to diagnosis and the use of imaging, and five to the assessment of the disease, its activity and comorbidities. Non-pharmacological therapies are the subject of one recommendation. Three recommendations concern initial treatment based on general corticosteroid therapy, five concern the reduction of corticosteroid therapy and follow-up, and two concern corticosteroid dependence and steroid-sparing treatments (anti-IL-6). CONCLUSION: These recommendations take account of current data on PMR, with the aim of reducing exposure to corticosteroid therapy and its side effects in a fragile population. They are intended to be practical, to help practitioners in the day-to-day management of patients with PMR.

The effect of prednisolone and a short-term prednisolone discontinuation for the diagnostic accuracy of FDG-PET/CT in polymyalgia rheumatica-a prospective study of 101 patients.

PURPOSE: 2-[18F]Fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) has been suggested as an imaging modality to diagnose polymyalgia rheumatica (PMR). However, the applicability of FDG-PET/CT remains unclear, especially following glucocorticoid administration. This study aimed to investigate the diagnostic accuracy of FDG-PET/CT before and during prednisolone treatment, as well as following short-term prednisolone discontinuation. METHODS: Treatment naïve suspected PMR patients were clinically diagnosed at baseline and subsequently had an FDG-PET/CT performed. Patients diagnosed with PMR were administered prednisolone following the first FDG-PET/CT and had a second FDG-PET/CT performed after 8 weeks of treatment. Subsequently, prednisolone was tapered with short-term discontinuation at week 9 followed by a third FDG-PET/CT at week 10. An FDG-PET/CT classification of PMR/non-PMR was applied, utilizing both the validated Leuven score and a dichotomous PMR score. The final diagnosis was based on clinical follow-up after 1 year. RESULTS: A total of 68 and 27 patients received a final clinical diagnosis of PMR or non-PMR. A baseline FDG-PET/CT classified the patients as having PMR with a sensitivity/specificity of 86%/63% (Leuven score) and 82%/70% (dichotomous score). Comparing the subgroup of non-PMR with inflammatory diseases to the PMR group demonstrated a specificity of 39%/54% (Leuven/dichotomous score). After 8 weeks of prednisolone treatment, the sensitivity of FDG-PET/CT decreased to 36%/41% (Leuven/dichotomous score), while a short-term prednisolone discontinuation increased the sensitivity to 66%/60%. CONCLUSION: FDG-PET/CT has limited diagnostic accuracy for differentiating PMR from other inflammatory diseases. If FDG-PET/CT is intended for diagnostic purposes, prednisolone should be discontinued to enhance diagnostic accuracy. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04519580). Registered 17th of August 2020.

Immune Checkpoint Inhibitor-induced Polymyalgia Rheumatica.

Polymyalgia rheumatica (PMR) immune-related adverse events (ICI-PMRs) represent a novel, distinct entity, despite many clinical, laboratory, and imaging similarities to classical PMR. Important questions remain in differentiating ICI-PMR from classical PMR, as well as other immune-related adverse events and PMR mimics. Despite this, ICI-PMR currently takes treatment cues from classical PMR, albeit with considerations relevant to cancer immunotherapy. Comparisons between ICI-PMR and classical PMR may provide further bidirectional insights, especially given that important questions remain unanswered about both diseases. The cause of classical PMR remains poorly understood, and ICI-PMR may represent a model of induced PMR, with important therapeutic implications.

Rheumatology: What You May Have Missed in 2023.

Many patients with rheumatologic conditions receive care from physicians other than rheumatologists. Here we note key findings from 6 studies in rheumatology published in 2023 that offer valuable insights for internal medicine specialists and subspecialists outside of rheumatology. The first study investigated the effect of low-dose glucocorticoids on patients with rheumatoid arthritis (RA) over 2 years and challenged existing perceptions about the risks of glucocorticoids in this setting. The second study focused on the updated guideline for preventing and treating glucocorticoid-induced osteoporosis. With the chronic and widespread use of glucocorticoids, the American College of Rheumatology emphasized the importance of assessing fracture risk and initiating pharmacologic therapy when appropriate. The third study explored the potential use of methotrexate in treating inflammatory hand osteoarthritis, suggesting a novel approach to managing this challenging and common condition. The results of the fourth article we highlight suggest that sarilumab has promise as an adjunct treatment of polymyalgia rheumatica relapse during glucocorticoid dosage tapering. The fifth study evaluated sublingual cyclobenzaprine for fibromyalgia treatment, noting both potential benefits and risks. Finally, the sixth article is a systematic review and meta-analysis that assessed the therapeutic equivalence of biosimilars and reference biologics in the treatment of patients with RA. Knowledge of this recent literature will be useful to clinicians regardless of specialty who care for patients with these commonly encountered conditions.

Outcomes of polymyalgia rheumatica in real-world practice: a longitudinal cohort study.

Background: Polymyalgia rheumatica (PMR) is an inflammatory condition closely linked with giant cell arteritis, which is a large vessel vasculitis. To provide real-world evidence on PMR outcomes and their determinants, we conducted a longitudinal study focusing on symptom relief and acute phase reactant normalization. Methods: We followed patients with PMR who were registered in Tabriz University of Medical Sciences Vasculitis Registry (TUOMS-VR) until February 2023. We measured sustained remission (primary outcome) and secondary outcomes including glucocorticoids (GCs)-free remission, medication-free remission, relapse rate and disease-induced damage. Results: We identified eighty-one patients with PMR and followed them for a median time of 57 months. In a median duration of 3 weeks, 98.8% of patients achieved symptom control, with 86.4% achieving sustained remission in a median duration of 9 weeks. Sustained remission was more common in non-smokers and adherent to therapy patients. Relapse occurred in 22.1% of patients, primarily due to non-adherence. Medication-free remission was observed in 30.9% of patients, especially among females and those with an initial prednisolone dose > 15 mg/d. Damage occurred in 42.0% of patients. Conclusion: Although sustained remission in PMR is not an unattainable goal in daily practice and most patients are in remission at the last visit, two-thirds of patients require long-term treatment.

Concordance and agreement between different activity scores in polymyalgia rheumatica.

OBJECTIVE: The C reactive protein polymyalgia rheumatica activity score (CRP-PMR-AS) is a composite index that includes CRP levels and was developed specifically for PMR. As treatments such as interleukin-6 antagonists can normalise CRP levels, the erythrocyte sedimentation rate (ESR) of PMR-AS, the clinical (clin)-PMR-AS and the imputed-CRP (imp-CRP)-PMR-AS have been developed to avoid such bias. Our primary objective was to measure the correlation of these activity scores. Our secondary objective was to evaluate the concordance between different cutoffs of the PMR-ASs. METHOD: Data from the Safety and Efficacy of tocilizumab versus Placebo in Polymyalgia rHeumatica With glucocORticoid dEpendence (SEMAPHORE) trial, a superiority randomised double-blind placebo-controlled trial, were subjected to post hoc analysis to compare the efficacy of tocilizumab versus placebo in patients with active PMR. The CRP-PMR-AS, ESR-PMR-AS, clin-PMR-AS and imp-CRP-PMR-AS were measured at every visit. The concordance and correlation between these scores were evaluated using kappa correlation coefficients, Bland-Altman correlations, intraclass correlation coefficients (ICCs) and scatter plots. RESULTS: A total of 101 patients were included in the SEMAPHORE trial, and 100 were analysed in this study. The correlation between the PMR-ASs was excellent, as the ICC and kappa were >0.85 from week 4 until week 24 (CRP-PMR-AS ≤10 or >10). Bland-Altman plots revealed that the differences between the CRP-PMR-AS and the other threescores were low. The cut-off values for the clin-PMR-AS were similar to those for the CRP-PMR-AS 86% of the time. CONCLUSION: The correlation between all the PMR-ASs was excellent, reflecting the low weight of CRP. In clinical trials using drugs that have an impact on CRP, the derived activity scores can be used. TRIAL REGISTRATION NUMBER: NTC02908217.

The usefulness of 18F-FDG-PET/CT in detecting musculoskeletal and vascular involvement in patients with polymyalgia rheumatica receiving glucocorticoids.

OBJECTIVE: Fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT is a promising diagnostic tool for polymyalgia rheumatica (PMR) and large vessel vasculitis (LVV). PET/CT performance is recommended before the onset of steroid therapy because glucocorticoids (GC) may decrease the intensity of FDG uptake. However, this is not always possible in clinical practice. Our aim was to assess if PET/CT could be also useful to detect musculoskeletal and vascular involvement in patients receiving GC. METHODS: Single-center study of patients with PMR diagnosis based on 2012 EULAR/ACR criteria who underwent a PET/CT scan due to LVV suspicion. We compared the musculoskeletal and vascular FDG uptake between two groups: (a) steroid-naïve and (b) steroid-resistant patients. A sub-analysis was conducted in patients who were receiving GC to discern if the cumulative prednisone dose influences the FDG uptake. RESULTS: We evaluated 75 patients (27 men/ 48 women); mean age±SD: 68.2 ± 10.7 years. PET/CT was performed in 14 steroid-naïve and 61 steroid-resistant patients. Patients under GC had received a median cumulative prednisone dose of 1.8 [0.6-3.9] g. The pattern of musculoskeletal FDG uptake was similar in steroid-naïve and steroid-resistant patients. FDG uptake in the vessel wall was more frequently detected in steroid-naïve patients. However, PET/ CT was also useful to detect LVV in 62.3 % of the patients who were receiving GC. The percentage of patients who had positive PET/CT scans tended to decrease with higher cumulative prednisone doses. CONCLUSION: Even though GC therapy may decrease the 18-FDG uptake, PET/CT continues to be a useful tool to detect musculoskeletal and LVV involvement in PMR.

Review of phase 2/3 trials in polymyalgia rheumatica and giant cell arteritis.

INTRODUCTION: GCA (giant cell arteritis) and PMR (polymyalgia rheumatica) are two overlapping inflammatory rheumatic conditions that are seen exclusively in older adults, sharing some common features. GCA is a clinical syndrome characterized by inflammation of the medium and large arteries, with both cranial and extracranial symptoms. PMR is a clinical syndrome characterized by stiffness in the neck, shoulder, and pelvic girdle muscles. Both are associated with constitutional symptoms. AREAS COVERED: In this review, we assess the established and upcoming treatments for GCA and PMR. We review the current treatment landscape, completed trials, and upcoming trials in these conditions, to identify new and promising therapies. EXPERT OPINION: Early use of glucocorticoids (GC) remains integral to the immediate management of PMR and GCA but being aware of patient co-morbidities that may influence treatment toxicity is paramount. As such GC sparing agents are required in the treatment of PMR. Currently there are limited treatment options available for PMR and GCA, and significant unmet needs remain. Newer mechanisms of action, and hence therapeutic options being studied include CD4 T cell co-stimulation blockade, IL-17 inhibition, IL-12/23 inhibition, GM-CSF inhibition, IL-1ß inhibition, TNF-α antagonist and Jak inhibition, among others, which will be discussed in this review.