One potential disadvantage of using anti-IL-6 therapies is that they lower inflammatory markers, such as the erythrocyte sedimentation rate and C-reactive protein, explained Dr. Spiera, which means they are no longer available as reliable biomarkers of disease activity. In some cases, he argued, it can be helpful to have that information, especially in patients presenting with monocular blindness.
Dr. Spiera highlighted some technical aspects of the phase 3 GIACTA trial of tocilizumab in GCA, which demonstrated improved glucocorticoid-free remission with use of the anti-IL-6 therapy.3 However, Dr. Spiera also argued that evidence from that or other studies hasn’t clearly demonstrated that IL-6 inhibitors reduce major complications related to glucocorticoid use. He acknowledged, however, that one analysis suggested a benefit in patient-reported outcomes of quality of life and function with early use of tocilizumab.4
Dr. Spiera shared that one approach to managing an initial presentation of GCA is to start with glucocorticoids alone, with a target of tapering within six months. In this scenario, he recommends not necessarily escalating steroid therapy to try to get inflammatory markers within a normal range (in the absence of clinical signs or symptoms of active disease), thus reducing overtreatment and glucocorticoid toxicities. (Patients with vision loss early in their disease course are an important possible exception.)
In discussing PMR, Dr. Spiera noted the efficacy and low cost of corticosteroids. He explained that because PMR doesn’t show clear evidence of disease-related damage, the concept of disease modification may not apply to the condition, so the advantage of using a biologic isn’t convincing from that angle. He also underscored that not all patients require a long course of therapy, and corticosteroids are potentially dangerous or poorly tolerated in some patients with PMR, but not all.
Dr. Spiera suggested that clinicians consider that PMR is not organ or life threatening, and its disease flares are manageable. He also noted that a relatively rapid glucocorticoid taper is possible in a substantial proportion of patients, even without the introduction of glucocorticoid-sparing therapies. Thus, he advised clinicians to plan a rapid glucocorticoid taper (to zero by month four).
Dr. Spiera underscored that for both disorders, it’s not yet clear that initial treatment with IL-6 inhibition results in fewer disease-related symptoms or overall toxicities. He also noted the value in selecting out the potentially easy to treat patients, who may be less well represented in trials, particularly trials currently available for PMR.5 A subset of patients may be effectively treated with glucocorticoids, using rapid tapers to reduce toxicities.
