Vitamin B12: a Biological Marker of Systemic Disease or Infection Flare-up in Patients Treated with Tocilizumab?
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 56
- 试验地点
- 1
- 主要终点
- Variationof serum level of vitamin B12 (pmol/L) between a clinical suspicion of relapse autoimmune or autoinflammatory desease (AI/ID) or infection and a remission state, in patients treated by tocilizumab.
研究概览
简要总结
Tocilizumab is a monoclonal antibody that acts as an IL-6 receptor antagonist It is responsible for a reduction in the hepatic synthesis of inflammatory proteins, including CRP (C-reactive protein).
Thus, the diagnosis of a relapse of the autoimmune or auto inflammatory disease (AI/ID) or an infection is made difficult in patients treated with tocilizumab and there is to date no marker of inflammation validated in patients receiving tocilizumab.
Vitamin B12 is an essential element that participates to haematopoiesis, myelin integrity, neuronal function and DNA synthesis. Vitamin B12 is carried by haptocorrin and transcobalamin II (TCII). Vitamin B12 increases in many pathological situations, including infections and AI/ID due to the increase of its transport proteins elevation (mostly transcobalamin II).
The sponsor did not find any study in the literature studying the level of vitamin B12 or TCII in patients taking tocilizumab. The sponsor also did not find any physiopathological argument in favor of an inhibition of TCII synthesis by tocilizumab.
As such, TCII dosage could be of interest, but the dosage is not available in routine whereas vitamin B12 dosage is available in every laboratory and is four times cheaper.
详细描述
The main objective is to study the variation in serum vitamin B12 level in case of clinical suspicion of AID/I flare or infection in patients treated with tocilizumab compared to the B12 level of the patient in remission period. , and excluding infection, under tocilizumab
Also, serum vitamin B12 will be measured during a biological assessment carried out either in the event of a suspected outbreak of MAI/I or infection, or in the event of remission (during the follow-up assessment carried out systematically in a patient on tocilizumab).
This determination of serum vitamin B12 will be carried out during a blood test carried out at the request of the patient's doctor.
The study will involve taking an additional tube of venous blood but will not result in additional venipuncture.
There will be no specific visit related to the study.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Diagnostic
- 盲法
- None
盲法说明
Each patient is his own witness to express the variation in the serum level of vitamin B12: this way we overcome individual variability.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age > 18 years old
- •Patient with:
- •A diagnosis of rheumatoid arthritis according to ACR EULAR 2010 classification criteria
- •Or a diagnosis of polymyalgia rheumatica according to ACR EULAR 2012 classification criteria
- •Or a diagnosis of giant cell arteritis (with or without polymyalgia rheumatica associated) according to 2022 revised classification criteria
- •Or a diagnosis of systemic sclerosis according to ACR EULAR 2013 classification criteria
- •Or a diagnosis of Takayasu vasculitis according to ACR 2022 classification criteria
- •Or a diagnosis of Still disease according to Yamaguchi or Fautrel classification criteria
- •Or a diagnosis of VEXAS with UBA1 somatic mutation
- •Or a diagnosis of unclassified autoimmune or auto-inflammatory disease treated by tocilizumab
- •Receiving intravenous or subcutaneous tocilizumab (treatment can be introduce before inclusion or started at the inclusion)
- •Capable of giving informed consent
- •Covered by a social protection system
排除标准
- •Patient treated by oral or subcutaneous vitamin B12
- •Pregnant or breastfeeding women
- •Patient under guardianship or curatorship, deprived or liberty, placed under judicial protection
- •Rejection to participate
结局指标
主要结局
Variationof serum level of vitamin B12 (pmol/L) between a clinical suspicion of relapse autoimmune or autoinflammatory desease (AI/ID) or infection and a remission state, in patients treated by tocilizumab.
时间窗: - At study inclusion - During the 3 years of the patient's participation and if included during a remission, new sample in case of suspicion of new infection or recurrence of autoimmune or inflammatory disease - During the 3 years of the patient's par
Percentage change of vitamin B12 serum level (pmol/L) between a remission state without infection ongoing and an relapse AI/ID or an infection.
次要结局
- Description of distribution of patients according to occurrence infection or AI/ID desease.(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according the events(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according event under treatment(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according the duration of treatment by tocilizumab(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according Previous AI/ID treatment(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according patients characteristics(from enrollment to the 3 years of the patient's participation)
- Comparaison of the level serum vitamin B12 level (pmol/L) in relapse AI/ID or infection with other inflammatory markers:(from enrollment to the 3 years of the patient's participation)
- variation of serum vitamin B12 level (pmol/L) according the way of tocilizumab administration(from enrollment to the 3 years of the patient's participation)
- To compare vitamin B12 serum level (in pmol/L) variation between: infection with tocilizumab / relapse AI/ID with or without tocilizumab / remission state with tocilizumab(from enrollment to the 3 years of the patient's participation)
- To study presence of a vitamin B12 serum level (in pmol/L) greater than upper laboratory bound if infection or relapse AI/ID (without tocilizumab) and to compare objectives cited in 2 according to this serum level.(from enrollment to the 3 years of the patient's participation)