Methotrexate - Inadequate Response Device Sub-Study

An AE is any new unfavorable symptom, sign, or disease or worsening of a preexisting condition that does not necessarily have a causal relationship with treatment. An SAE is any unfavorable medical event that at any dose results in death, persistent or significant disability/incapacity, or drug dependency or abuse; is life-threatening, an important medical event, or a congenital anomaly/birth defect; or requires or prolongs hospitalization. Treatment-related=possibly, probably, or certainly related to and of unknown relationship to study treatment.

AE=any new untoward medical occurrence or worsening of a preexisting medical condition which does not necessarily have a causal relationship with this treatment. AEs of special interest are those AEs that may be associated with the use of immunomodulatory drugs including all infections, local injection reactions (prespecified), and systemic injection reactions (within 24 hours of dosing).

BL=baseline; LLN lower limit of normal; ULN=upper limit of normal. Marked abnormality criteria: Hemoglobin: >3 g/dL decrease from BL; Hematocrit: <0.75*BL; Erythrocytes: <0.75*BL; Platelets: <0.67*LLN/>1.5*ULN, or if BL <LLN, use 0.5*BL/<100,000 mm^3; Leukocytes: <0.75*LLN/ >1.25*ULN, or if BL<LLN, use <0.8*BL/>ULN, or if BL>ULN, use >1.2*BL/<LLN; neutrophils+bands: <1.0*10^3 c/uL; eosinophils: >0.750*10^3 c/uL; basophils: >400 mm^3; monocytes: >2000 mm^3; lymphocytes: <0.750*10^3 c/uL/ >7.50*10^3 c/uL.

Marked abnormality criteria: Alkaline phosphatase (ALP): >2* ULN, or if BL>ULN then use >3* BL; aspartate aminotransferase (AST): >3* ULN, or if BL>ULN then use >4* BL; alanine aminotransferase (ALT): >3* ULN, or if BL>ULN then use >4* BL; G-Glutamyl transferase (GGT): >2* ULN, or if BL>ULN then use >3* BL; Bilirubin: >2* ULN, or if BL>ULN then use >4* BL; blood urea nitrogen (BUN): >2* BL; creatinine: >1.5* BL

Marked abnormality criteria: Sodium (Na): <0.95*LLN/ >1.05*ULN, or if BL<LLN then use <0.95* BL or >ULN, or if BL>ULN then use>1.05* BL or <LLN; potassium (K): <0.9* LLN/>1.1*ULN, or if BL<LLN then use <0.9* BL or >ULN, or if BL>ULN then use>1.1* BL or <LLN; (Cl): <0.9* LLN/>1.1* ULN, or if BL<LLN then use <0.9* BL or >ULN, or if BL>ULN then use>1.1* BL or <LLN; calcium (Ca): <0.8* LLN/>1.2* ULN, or if BL<LLN then use <0.75* BL or >ULN, or if BL>ULN then use>1.25* BL or <LLN; phosphorous (P): <0.75* LLN/ >1.25* ULN, or if BL<LLN then use 0.67* BL or >ULN, or if BL>ULN then use>1.33* BL or <LLN

MA criteria: serum glucose (Glu): <65 mg/dL/>220 mg/dL;fasting serum Glu: <0.8* LLN/>1.5*ULN,or if BL<LLN then use 0.8*BL or >ULN,or if BL>ULN then use >2.0*BL or <LLN;total protein: <0.9*LLN/>1.1*ULN,or if BL<LLN then use <0.9*BL or >UNL,or if BL>UNL then use >1.1*BL or <LLN; albumin: <0.9*LLN,or if BL<LLN then use <0.75 BL;uric acid: >1.5*ULN,or if BL>ULN then use >2*BL. Urinalysis (Urine protein,urine Glu,urine blood,leukocyte esterase,Red Blood Cells [RBCs], White Blood Cells [WBCs]):Use ≥2 when BL value missing or when pre-dose=0 or 0.5; use ≥3 when pre-dose=1, use ≥4 when pre-dose=2 or 3

Trough levels of abatacept were evaluated based upon serum samples. Day 1 pharmacokinetics were based on exposure to the pre-filled syringes and did not reflect abatacept exposure via the ACP device.

Serum samples from all treated adult participants with active rheumatoid arthritis were screened for the presence of drug-specific antibodies using ELISA. Immunogenicity was defined as the presence of a positive anti-abatacept or anti-CTLA4 antibody.

An electrochemiluminescence immunoassay screened sera for drug-specific antibodies; immunocompetition was used to identify specific anti-Abatacept reactivity. CTLA4 and Possibly immunoglobulin (Ig) category=reactivity against extracellular domain of human CTLA4, constant regions of human IgG1, or both (CTLA4Ig; Abatacept molecule). Ig and/or Junction (JNCT)category=reactivity against constant regions and/or hinge region of human IgG1. Drug-induced seropositivity defined as a post-baseline titer higher than Baseline, or any post-baseline positivity if Baseline value was missing. TRT=treatment