In this article, we will discuss Abatacept (Dosage). So, let’s get started.
Abatacept
ORENCIA® (abatacept) is a soluble fusion protein that consists of the extracellular domain of human cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) linked to the modified Fc (hinge, CH2, and CH3 domains) portion of human immunoglobulin GI (IgGI). Abatacept is produced by recombinant DNA technology in a mammalian cell expression system. The apparent molecular weight of abatacept is 92 kilodaltons.
ORENCIA® (abatacept) is supplied as a sterile, white, preservative-free, lyophilized powder for parenteral administration. Following reconstitution with 10 mL of Sterile Water for Injection, USP, the solution of ORENCIA® (abatacept) is clear, colorless to pale yellow. with a pH range of 7.0 to 8.0. Each single-use vial of ORENCIA provides 250 mg abatacept, 500 mg maltose, 17.2 mg monobasic sodium phosphate, and 14.6 mg sodium chloride for administration
Mechanism of Action
Abatacept, a selective costimulation modulator, inhibits T cell (T-lymphocyte) activation by binding to CD80 and CD86, thereby blocking interaction with CD28. This interaction provides a costimulatory signal necessary for full activation of T lymphocytes, implicated in the pathogenesis of rheumatoid arthritis (RA). Activated T lymphocytes are found in the synovium of patients with RA.
In vitro, abatacept decreases T cell proliferation and inhibits the production of the cytokines tumor necrosis factor alpha (TNF), interferon-γ. and interleukin-2. In a rat collagen-induced arthritis model, abatacept suppresses inflammation, decreases anti-collagen antibody production, and reduces antigen specific production of interferon-γ.
The relationship of these biological response markers to the mechanisms by which ORENCIA® (abatacept) exerts its effects in RA is unknown.
Dosage
ORENCIA® (abatacept) should be administered as a 30-minute intravenous infusion at the dose specified below. Following the initial administration, ORENCIA® (abatacept) should be given at 2 and 4 weeks after the first infusion, then every 4 weeks thereafter. ORENCIA® (abatacept) may be used as monotherapy or concomitantly with disease-modifying, anti-rheumatic drugs (DMARDs) other than TNF antagonists.
Dose of ORENCIA® (abatacept)
Body Weight of Patient – Dose – Number of Vials*
<60 kg – 500 mg – 2
60 to 100 kg – 750 mg – 3
>100 kg – 1 gram – 4
*Each vial provides 250 mg of abatacept for administration.