FDA Approves Sarilumab for pJIA

In June 2024, sarilumab, an interleukin (IL) 6 receptor antagonist administered as a subcutaneous injection, garnered its first pediatric indication from the U.S. Food & Drug Administration (FDA). The treatment is now approved to treat active polyarticular juvenile idiopathic arthritis (pJIA) in patients who weigh at least 63 kgs.¹

The FDA initially approved sarilumab in May 2017 for the treatment of adults with moderate to severe active rheumatoid arthritis (RA) for whom one or more disease-modifying anti-rheumatic drugs (DMARDs) had proved inadequate or intolerable.² In 2023, sarilumab was approved to treat polymyalgia rheumatica in adults who’ve had an inadequate response to corticosteroids or who could not tolerate tapering corticosteroids.³

This recent FDA approval is supported by findings from studies in adults with RA, pharmacokinetic data from adults with RA and a pharmacokinetic, pharmacodynamic, dose-finding and safety study in pediatric patients with pJIA aged 2 years and older.⁴

Sarilumab in pJIA

In patients with pJIA, sarilumab can be used alone or in combination with conventional DMARDs. The recommended dose in these patients is a 200 mg injection given once every two weeks for patients who weigh at least 63 kg. Sarilumab is not approved in pediatric patients who weigh less than 63 kg because no dose is available for this population.⁴

The most common adverse effects seen in patients with pJIA taking sarilumab were nasopharyngitis, neutropenia, upper respiratory tract infection and injection site redness.⁵ Sarilumab should not be started in patients with an absolute neutrophil count less than 2,000/mm³, a platelet count less than 150,000/mm³ or liver transaminases more than 1.5 times the upper limit of normal.² (Note: Dose reduction due to cytopenias caused by sarilumab in pediatric patients with pJIA has not been studied.)

Risks: Sarilumab has a boxed warning about serious infections leading to hospitalization or death, including bacterial, viral, invasive fungal and other opportunistic infections.⁴

If a serious infection develops in a patient, sarilumab should be stopped until the infection is controlled. Also, cases of tuberculosis in patients taking sarilumab have been reported. Therefore, it’s recommended patients be tested for latent tuberculosis prior to starting the sarilumab. If a patient tests positive, tuberculosis treatment should be started. Finally, throughout treatment with sarilumab, patients should be closely monitored for signs and symptoms of infection.

No new adverse reactions or safety signals were identified in the pJIA population compared with the adult RA population.