• See Also
  1. DMARD
  2. Rheumatoid Arthritis
  3. Psoriatric Arthritis
  • Indications
  1. Refractory, moderate to severe Rheumatoid Arthritis
  2. Active Rheumatoid Arthritis
  3. Juvenile Idiopathic Arthritis (JIA, moderate to severe)
  • Contraindications
  1. Do not use with TNF Inhibitors, Anankira, Tofacitinib
  2. Do not use with Live virus Vaccine 3 months before, during or 3 months after last dose
    1. Update Vaccinations (both live and passive) before starting Abatacept
  3. Stop Abatacept if serious infection occurs
  • Mechanism
  1. Abatacept is a fusion Protein of a receptor bound to the IgG Fc fragment (similar to Etanercept)
    1. Extracellular CTLA4 fused to IgG Fc of IgG1
    2. IgG Fc Fragment
      1. idAntibody.jpg
  2. Abatacept is a T-Cell Co-Stimulatory Blocker
    1. T-Cells are stimulated via CD3 with co-stimulation via various agents including CD28
      1. Abatacept inhibits CD28 to CD80/CD66 binding
    2. CD28 Inhibition
      1. Increases T-Cell Activation threshold and inhibits T-Cell proliferation
    3. Images
      1. BCellActivation.jpg
  • Medications
  1. General
    1. Keep refrigerated until 30 to 60 min before injection
    2. Protect from light
  2. Formulations
    1. Autoinjector: 125 mg/ml (adults or weight >=50 kg)
    2. Prefilled syringes: 50 mg/0.4 ml, 87.5 mg/0.7 ml, 125 mg/ml
    3. Intravenous infusion
  3. Administration
    1. Allow to warm to room Temperature for 30 to 60 minutes before injection
    2. Subcutaneous Injection is in thigh, Abdomen or outer upper arm
  • Dosing
  • Adult
  1. Intravenous (IV)
    1. IV infusion: 10 mg/kg to 500, 750 or 1000 mg over 30 minutes
      1. Weight <60 kg: 500 mg
      2. Weight 60 to 100 kg: 750 mg
      3. Weight >100 kg: 1000 mg
    2. IV Dosing Interval
      1. Give at 0, 2 and 4 weeks and then every 4 weeks (or transition to SQ dosing)
  2. Subcutaneous (SQ)
    1. Give 125 mg SQ weekly in thigh, Abdomen or outer upper arm
    2. Transitioning from IV to SQ dosing
      1. Give on the next day after the first IV dose OR
      2. At the next scheduled IV dose after regular IV dosing
  • Dosing
  • Child
  1. Indicated for Juvenile Idiopathic Arthritis
  2. Intravenous (IV, age 6 years and older)
    1. Use adult dose (see above) for weight >=75 kg
    2. IV infusion: 10 mg/kg up to maximum of 1000 mg over 30 minutes
    3. Give at 0, 2 and 4 weeks and then every 4 weeks (or transition to SQ dosing)
  3. Subcutaneous (SQ, age 2 years and older)
    1. Weight 10 to 25 kg: 50 mg
    2. Weight 25 to 50 kg: 87.5 mg
    3. Weight >=50 kg: 125 mg
  • Pharmacokinetics
  1. Half-Life: 13 to 17 days
  • Adverse Effects
  1. Hypersensitivity (including Anaphylaxis)
  2. Serious infections
    1. Higher risk of pulmonary infections in comorbid COPD
  3. Latent infection reactivation
    1. Tuberculosis reactivation
    2. Hepatitis BVirus Infection reactivation
    3. Cytomegalovirus (CMV) Reactivation
    4. Epstein-Barr Virus (EBV) Reactivation
  4. Common
    1. Headache
    2. Upper Respiratory Infection
    3. Nausea
  • Safety
  1. Unknown safety in pregnancy
  2. Avoid in Lactation
  • Drug Interactions
  1. Glucose monitoring test strips (using GDH-PQQ)
    1. Falsely elevated Glucose readings (IV Abatacept contains maltose)
  • Resources
  1. Abatacept Injection Solution (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=0836c6ac-ee37-5640-2fed-a3185a0b16eb