Tapering of biological treatment in autoinflammatory diseases: a scoping review.

BACKGROUND: Biological treatment and treat-to-target approaches guide the achievement of inactive disease and clinical remission in Autoinflammatory Diseases (AID). However, there is limited evidence addressing optimal tapering strategies and/or discontinuation of biological treatment in AID. This study evaluates available evidence of tapering biological treatment and explores key factors for successful tapering. METHODS: A systematic literature search was conducted in Embase, MEDLINE, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials using the OVID platform (1990-08/2020). Bibliographic search of relevant reviews was also performed. Studies/case series (n ≥ 5) in AID patients aged ≤ 18 years with biological treatment providing information on tapering/treatment discontinuation were included. After quality assessment aggregated data were extracted and synthesized. Tapering strategies were explored. RESULTS: A total of 6035 records were identified. Four papers were deemed high quality, all focused on systemic juvenile idiopathic arthritis (sJIA) (1 open-label randomized trial, 2 prospective, 1 retrospective observational study). Biological treatment included anakinra (n = 2), canakinumab (n = 1) and tocilizumab (n = 1). Strategies in anakinra tapering included alternate-day regimen. Canakinumab tapering was performed randomized for dose reduction or interval prolongation, whereas tocilizumab was tapered by interval prolongation. Key factors identified included early start of biological treatment and sustained inactive disease. CONCLUSION: Tapering of biological treatment after sustained inactive disease should be considered. Guidance for optimal strategies is limited. Future studies may leverage therapeutic drug monitoring in combination with pharmacometric modelling to further enhance personalized "taper-to-target" strategies respecting individual patients and diseases aspects.

Variant in the PLCG2 Gene May Cause a Phenotypic Overlap of APLAID/PLAID: Case Series and Literature Review.

Background: Variants in the phospholipase C gamma 2 (PLCG2) gene can cause PLCG2-associated antibody deficiency and immune dysregulation (PLAID)/autoinflammation and PLCG2-associated antibody deficiency and immune dysregulation (APLAID) syndrome. Linking the clinical phenotype with the genotype is relevant in making the final diagnosis. Methods: This is a single center case series of five related patients (4−44 years), with a history of autoinflammation and immune dysregulation. Clinical and laboratory characteristics were recorded and a literature review of APLAID/PLAID was performed. Results: All patients had recurrent fevers, conjunctivitis, lymphadenopathy, headaches, myalgia, abdominal pain, cold-induced urticaria and recurrent airway infections. Hearing loss was detected in two patients. Inflammatory parameters were slightly elevated during flares. Unswitched B-cells were decreased. Naïve IgD+CD27− B-cells and unswitched IgD+CD27+ B-cells were decreased; switched IgD-CD27+ B-cells were slightly increased. T-cell function was normal. Genetic testing revealed a heterozygous missense variant (c.77C>T, p.Thr26Met) in the PLCG2 gene in all patients. Genotype and phenotype characteristics were similar to previously published PLAID (cold-induced urticaria) and APLAID (eye inflammation, musculoskeletal complaints, no circulating antibodies) patients. Furthermore, they displayed characteristics for both PLAID and APLAID (recurrent infections, abdominal pain/diarrhea) with normal T-cell function. Conclusion: The heterozygous missense PLCG2 gene variant (c.77C>T, p.Thr26Met) might cause phenotypical overlap of PLAID and APLAID patterns.