Prolonged remission after stop of tocilizumab for patients with giant cell arteritis

Treatment with tocilizumab not only led to a reduction in cumulative steroid intake in giant cell arteritis (GCA), but many patients profited from ongoing remission after drug discontinuation [1].

In terms of sustained glucocorticoid-free remission in patients with GCA, therapy with weekly or biweekly tocilizumab 162 mg plus 26-week prednisone tapering demonstrated to be superior to placebo plus 26-week or 52-week prednisone tapering, in the first part of the GiACTA trial [2].

Of included patients from part 1 of GiACTA, 215 entered an open-label second part of the phase 3 trial in order to investigate continued 2-year safety as well as maintenance of efficacy after the stop of treatment with tocilizumab [1]. Data on the amount of steroid use was also analysed. Status of clinical remission was defined by the absence of flare, without requirement of normalisation of C-reactive protein <1 mg/dL. Blinded injections were terminated at week 52 of part 1. Depending on the status of the disease, the investigators were able to choose to treat or terminate treatment with tocilizumab and/or glucocorticoid in part 2 in case of a flare.

“Of the patients who received tocilizumab weekly during the original trial, 42% showed complete remission over the following 24 months,” said Prof. John H. Stone (Harvard Medical School, Boston, USA). A median period of 575 or 428 days elapsed for the tocilizumab patients of weekly or biweekly dosing scheme before the first flare occurred. Respective time spans for the placebo arms were 162 or 295 days, depending on steroid tapering over 26 or 52 weeks. In case of a flare, treatment with tocilizumab with or without combination of steroid was able to restore remission in 8.5 or 15.0 days. Therapy with glucocorticoid only took a median of 37.5 days to reach the same goal. The median cumulative dose of glucocorticoid over the entire 3 years was lowest in the group receiving tocilizumab every week (2,647 mg), followed by the arm of tocilizumab every other week (3,782 mg). Both placebo groups had much higher need for steroids (5,248 mg and 5,323 mg).

New safety issues were not observed: over the 3 years of part 1 plus part 2, rates for serious infections per 100 patient-years were 4.6 for patients who never received tocilizumab and 3.5 for those who took ≥1 dose of tocilizumab. “Patients should start on tocilizumab as soon as they are diagnosed. The goal should be to get them off steroids as quickly as possible and maintain their response with tocilizumab,” concluded Prof. Stone. Obviously, steroids are inexpensive and work rapidly for the majority of GCA patients and the field is a long way from such a global strategy. Tocilizumab therapy for the disease and its use for the foreseeable future in the real world will be reserved for steroid-resistant severe disease.

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   1.  Stone J, et al. Abstract 808. ACR 2019. 8-13 November, Atlanta (GA/USA).
   2. Stone J, et al. N Engl J Med. 2017;377:317-28.

 



Posted on 4 February 202012 March 2021