Sarilumab, an injectable biologic that blocks a key inflammatory signaling molecule called interleukin-6, is the first and currently only steroid-sparing drug approved specifically for polymyalgia rheumatica (PMR) in both the United States and Europe. Its approval marks a genuine turning point for a condition that has been managed almost exclusively with glucocorticoids for decades, often at considerable cost to patients’ long-term health. But sarilumab is not the only drug generating interest; several other therapies, from JAK inhibitors to rituximab, are in various stages of clinical testing and could reshape how the disease is treated in the years ahead.
Why Glucocorticoids Alone Are Not Enough
Prednisone and its equivalents remain the backbone of PMR treatment because they work fast. Most people feel dramatically better within days of starting a dose in the range of 12.5 to 25 mg daily, and the goal is to taper down gradually, ideally over about 12 months. In practice, tapering rarely goes that smoothly. In a large cohort study, the median time it took patients to taper below 5 mg per day and stay there for six months was roughly a year and a half, and the median time to stop glucocorticoids entirely was nearly six years.1PubMed Central. Comparable Rates of Glucocorticoid-Associated Adverse Events in Patients With Polymyalgia Rheumatica and Comorbidities in the General Population Relapses during tapering are common, which often means bumping the dose back up and extending the overall course of treatment.
That prolonged steroid exposure comes with real consequences. The same cohort study found that patients with PMR had a higher risk of developing cataracts compared to matched controls. Weight gain, thinning bones, elevated blood sugar, mood disturbances, and increased infection susceptibility are all well-documented effects of long-term glucocorticoid use. These harms are not rare outliers; they are baked into the standard treatment course for a disease that disproportionately affects people over 50, who already carry higher baseline risks for many of these problems.1PubMed Central. Comparable Rates of Glucocorticoid-Associated Adverse Events in Patients With Polymyalgia Rheumatica and Comorbidities in the General Population The cumulative steroid dose at five years averaged over 6 grams in that study, which is a lot of glucocorticoid for a body to absorb.
This is the core problem that every newer therapy is trying to solve: how to get people off steroids faster without letting the disease flare back up.
Sarilumab, the First Approved Steroid-Sparing Drug
Sarilumab works by blocking the receptor for interleukin-6 (IL-6), a signaling protein that plays a central role in driving the systemic inflammation behind PMR. Fatigue, fever, and weight loss in PMR are thought to be largely driven by IL-6 signaling, so dampening that pathway addresses the disease at a more specific level than glucocorticoids, which suppress inflammation broadly.2PubMed Central. An update on polymyalgia rheumatica
The pivotal evidence came from a phase 3 trial published in the New England Journal of Medicine. In this study, patients whose PMR had relapsed during glucocorticoid tapering were randomized to receive either sarilumab injections every two weeks alongside a rapid 14-week steroid taper, or placebo injections alongside a standard 52-week taper. At one year, about 28% of patients on sarilumab had achieved sustained remission, compared to 10% in the placebo group. Just as importantly, the sarilumab group’s cumulative glucocorticoid dose over that year was dramatically lower: a median of 777 mg versus over 2,000 mg in the placebo group.3PubMed. Sarilumab for Relapse of Polymyalgia Rheumatica during Glucocorticoid Taper
A follow-up analysis of patient-reported outcomes from the same trial found that people on sarilumab reported meaningfully better physical and mental quality-of-life scores compared to placebo. More than half of sarilumab-treated patients reached quality-of-life scores at or above population norms for several measures, something no patients in the placebo group achieved across any domain. The improvements were most pronounced in people with more severe disease at baseline.4The Lancet Rheumatology. Sarilumab in relapsing polymyalgia rheumatica: patient-reported outcomes from a phase 3, double-blind, randomised controlled trial
Sarilumab is not without trade-offs. In the trial, the most common side effects compared to placebo were low white blood cell counts (neutropenia, seen in about 15% of sarilumab-treated patients versus none on placebo), joint pain, and diarrhea. About 12% of sarilumab patients stopped treatment due to side effects, compared to 7% in the placebo group.3PubMed. Sarilumab for Relapse of Polymyalgia Rheumatica during Glucocorticoid Taper Neutropenia requires monitoring through regular blood tests, and IL-6 blockade can also mask signs of infection by suppressing fever and inflammatory markers. These are real considerations, but for patients stuck on high-dose steroids with accumulating side effects, the trade-off is often worthwhile.
Tocilizumab, the Other IL-6 Blocker
Tocilizumab targets the same IL-6 receptor pathway as sarilumab and has been studied in PMR for longer, though it has not received a specific PMR approval. In an early open-label trial, all nine patients who completed the tocilizumab treatment course achieved relapse-free remission without any glucocorticoid use at six months, and that remission persisted through 15 months of follow-up. Every patient was able to stop steroids within four months.5PubMed Central. A Prospective Open-Label Phase IIa Trial of Tocilizumab in the Treatment of Polymyalgia Rheumatica
A more rigorous randomized trial (PMR-SPARE) tested tocilizumab against placebo in newly diagnosed patients undergoing rapid glucocorticoid tapering. About 63% of tocilizumab-treated patients achieved glucocorticoid-free remission by week 16, compared to roughly 12% on placebo. Tocilizumab also extended the average time before a first relapse and reduced cumulative steroid exposure.6PubMed. Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial These numbers are striking, though the trial was small. Tocilizumab is already approved for giant cell arteritis, a closely related condition that overlaps with PMR in a significant minority of patients, so many rheumatologists already have experience prescribing it. It is sometimes used off-label for PMR, particularly in patients who cannot tolerate or taper from glucocorticoids.
JAK Inhibitors on the Horizon
Janus kinase (JAK) inhibitors are oral medications already approved for rheumatoid arthritis and other inflammatory conditions, and they are now being tested in PMR. The appeal is obvious: a pill rather than an injection, and a different mechanism of action that could work for patients who do not respond well to IL-6 blockade.
Tofacitinib is the JAK inhibitor farthest along in PMR research. A small phase 2 study found that about 86% of tofacitinib-treated patients reached remission, with researchers noting a good safety profile and the potential to reduce glucocorticoid use.7PubMed. Efficacy and safety of tofacitinib in patients with polymyalgia rheumatica: a phase 2 study A larger randomized trial compared tofacitinib head-to-head against glucocorticoids in newly diagnosed patients over 24 weeks. Both groups had similar disease activity scores by the end, with all patients in each group reaching low disease activity. Inflammatory markers dropped comparably in both groups, and no severe adverse events occurred in either arm.8PLOS Medicine. Efficacy and Safety of Tofacitinib in Patients with Polymyalgia Rheumatica (EAST PMR): An open-label randomized controlled trial
A retrospective study from China comparing JAK inhibitors with conventional disease-modifying drugs also found comparable effectiveness, with the JAK inhibitor group using less glucocorticoid overall.9PubMed Central. Efficacy of JAK Inhibitors versus DMARDs in the Treatment of Polymyalgia Rheumatica in China The evidence is still early-stage, and JAK inhibitors carry their own safety concerns, including elevated risks of blood clots and certain infections that have been identified in their use for other conditions. But the preliminary results suggest these drugs could eventually join the treatment toolkit, particularly for patients who need an oral option.
Rituximab and B-Cell Depletion
Rituximab, a drug that depletes a specific population of immune cells called B cells, has shown proof-of-concept results in PMR. In a randomized trial, about 48% of rituximab-treated patients achieved glucocorticoid-free remission at 21 weeks, compared to 21% on placebo. That translates to roughly double the likelihood of getting off steroids.10The Lancet Rheumatology. Efficacy of rituximab for the treatment of polymyalgia rheumatica: a double-blind, randomised, placebo-controlled, proof-of-concept trial A one-year extension of that trial found that the proportion of patients in glucocorticoid-free remission remained stable after just a single 1,000 mg dose, and the steroid-sparing effect was still apparent.11PubMed. 1-year results of treatment with rituximab in polymyalgia rheumatica: an extension study of a randomised double-blind placebo-controlled trial
Rituximab is interesting because it works through a completely different mechanism than IL-6 blockers or JAK inhibitors, which suggests it could be useful for patients who fail those therapies. It is given as an intravenous infusion, typically in a clinic or hospital, and its immune-suppressing effects last for months after a single dose. Larger confirmatory trials are needed before it could become a standard option for PMR, but the early signal is encouraging.
Methotrexate, the Familiar Steroid-Sparing Option
Methotrexate has been used alongside glucocorticoids for PMR for years, but its track record is genuinely mixed. One randomized trial found no difference between methotrexate (at 7.5 mg weekly) and placebo in time to remission, relapse rate, or cumulative prednisone dose.12PubMed Central. Can methotrexate be used as a steroid sparing agent in the treatment of polymyalgia rheumatica and giant cell arteritis? Another randomized trial using methotrexate at 10 mg weekly told a different story: 28 of 32 patients on methotrexate were off prednisone by 76 weeks, compared to 16 of 30 on placebo, and methotrexate-treated patients had fewer flares and a lower total steroid dose.13PubMed. Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial
The conflicting results likely come down to dosing and patient selection. A review of real-world practice found that methotrexate is still the most commonly used steroid-sparing drug for PMR, typically started at 7.5 to 10 mg weekly, but the overall benefits reported in studies are generally small.14Rheumatology Advances in Practice. Effectiveness of methotrexate and leflunomide as corticoid-sparing drugs in patients with polymyalgia rheumatica Methotrexate is inexpensive, widely available, and well-understood, which keeps it in the conversation. But its effect size in PMR is modest compared to the newer biologics and JAK inhibitors, and it is not a realistic option for everyone because of its own side effect profile, particularly liver toxicity and its interaction with alcohol.
Therapies That Did Not Pan Out
Not every drug tested for PMR has delivered useful results, and knowing what failed helps put the successful candidates in context. Abatacept, a drug that modulates T-cell activation and is used in rheumatoid arthritis, was tested as a standalone first-line therapy for early PMR. While half of abatacept-treated patients achieved low disease activity at 12 weeks compared to about 22% on placebo, the difference was not statistically significant, and the researchers concluded that abatacept alone was not strong enough to justify larger studies in early PMR.15The Lancet Rheumatology. Abatacept in early polymyalgia rheumatica (ALORS): a proof-of-concept, randomised, placebo-controlled, parallel-group trial The investigators did note that their findings do not rule out a potential role for abatacept in patients who are dependent on glucocorticoids and cannot taper, a different clinical scenario than was tested.
Etanercept, a TNF-alpha blocker widely used for conditions like psoriatic arthritis and ankylosing spondylitis, was also tested as a standalone therapy in steroid-naïve PMR patients. It did reduce disease activity, but the effect was modest, leading researchers to conclude that TNF-alpha plays only a minor role in PMR’s underlying inflammation.16PubMed Central. Effect of etanercept in polymyalgia rheumatica: a randomized controlled trial This is a useful finding because it tells us something about the biology: PMR is driven more by IL-6 and related pathways than by TNF-alpha, which explains why IL-6 blockers have outperformed TNF blockers in trials.
What Might Come Next
Beyond the drugs already in clinical trials, a few emerging approaches are worth watching. IL-17 inhibitors, a class of biologics already used for psoriasis and some forms of spondyloarthritis, are being considered for PMR. And an intriguing compound called clofutriben takes a different tack entirely: rather than replacing glucocorticoids, it aims to reduce their toxicity. Clofutriben inhibits an enzyme involved in how glucocorticoids are metabolized in tissues, potentially allowing patients to get the anti-inflammatory benefit of steroids with fewer of the damaging side effects on bone, metabolism, and other organ systems. Early results have shown promise, though the drug is still in development.
Telling PMR Apart from Conditions That Mimic It
One reason treatment outcomes vary so much in PMR is that the condition can be hard to distinguish from several look-alikes, and getting the diagnosis wrong obviously means the “newest” treatment is beside the point. Elderly-onset rheumatoid arthritis is a common mimic. In one study, testing for anti-CCP antibodies proved useful: 65% of patients with elderly-onset rheumatoid arthritis tested positive for those antibodies, while no PMR patients did. Even among rheumatoid arthritis patients who initially presented with PMR-like symptoms, some were anti-CCP positive, making the test a strong clue that what looks like PMR might actually be RA requiring different treatment.17PubMed. Clinical utility of anti-CCP antibodies in the differential diagnosis of elderly-onset rheumatoid arthritis and polymyalgia rheumatica
Another increasingly recognized mimic is PMR triggered by immune checkpoint inhibitor cancer drugs. A study comparing checkpoint inhibitor-associated PMR to primary PMR found that patients with the drug-triggered version less frequently met standard classification criteria, and classic features like morning stiffness and elevated inflammatory markers were less common.18PubMed Central. Immune checkpoint inhibitor-mediated polymyalgia rheumatica versus primary polymyalgia rheumatica: comparison of disease characteristics and treatment requirement As cancer immunotherapy becomes more widespread, this type of PMR mimic is turning up more often, and it requires its own treatment considerations because managing the cancer therapy adds a layer of complexity.
Imaging and Monitoring Advances
Treatment decisions increasingly rely on better ways to see what the disease is actually doing in the body. FDG-PET/CT scanning, which highlights areas of active inflammation, has become a valuable tool for PMR. Characteristic patterns include high uptake around the shoulders, hips, and sternoclavicular joints, as well as in areas between spinal processes and near the pelvis.19PubMed Central. 18F-FDG PET/CT in polymyalgia rheumatica-a pictorial review A recent study found that standardized PMR-specific PET scoring systems were able to accurately distinguish PMR from non-inflammatory conditions in cases where routine scan reports were ambiguous.20Frontiers in Nuclear Medicine. 18F-FDG-PET/CT for polymyalgia rheumatica: agreement and diagnostic accuracy of routine PET scan report vs. standardized PMR PET scores
On the blood-test side, researchers have been working to identify which markers best track disease activity beyond the standard CRP and ESR tests. A study examining multiple serum markers found that fibrinogen and haptoglobin, in addition to CRP and ESR, showed very high sensitivity and specificity for distinguishing active disease from remission. Fibrinogen in particular achieved a perfect area-under-the-curve score in distinguishing baseline disease activity from remission.21Arthritis & Rheumatology. Serum Markers of Disease Activity in Polymyalgia Rheumatica Better biomarkers matter for treatment decisions because they help clinicians tell the difference between a true flare that needs more aggressive therapy and residual symptoms that might resolve on their own. As drugs like sarilumab suppress CRP and ESR directly through their mechanism of action, having additional markers to track disease activity independently becomes even more important.
Why PMR Is a Disease of Older Adults
Understanding why PMR almost exclusively strikes people over 50 is not just an academic question; it shapes how researchers think about which treatments to pursue next. Several age-related changes in the immune system converge to create vulnerability. The aging immune system becomes both less effective and paradoxically more prone to chronic low-grade inflammation, a phenomenon sometimes called “inflammaging.” Hormonal shifts, increased susceptibility to infections that can trigger immune reactions, and age-related changes in the gut microbiome have all been identified as potential contributing factors.22PubMed. Why is polymyalgia rheumatica a disease of older adults? Explanations through etiology and pathogenesis: a narrative review This means PMR is not simply one broken pathway that can be fixed with a single targeted drug. The disease arises from a tangle of age-related immune dysfunction, which is part of why no single therapy has emerged as a cure and why the treatment landscape involves multiple drugs aimed at different parts of the inflammatory cascade.