Abatacept

INDICATIONS AND USAGE ORENCIA is a selective T cell costimulation modulator indicated for: • the treatment of adult patients with moderately to severely active rheumatoid arthritis (RA). (1.1) • the treatment of patients 2 years of age and older with moderately to severely active polyarticular juvenile idiopathic arthritis (pJIA). (1.2) • the treatment of patients 2 years of age and older with active psoriatic arthritis (PsA). (1.3) • the prophylaxis of acute graft versus host disease (aGVHD), in combination with a calcineurin inhibitor and methotrexate, in adults and pediatric patients 2 years of age and older undergoing hematopoietic stem cell transplantation (HSCT) from a matched or 1 allele-mismatched unrelated donor. (1.4) Limitations of Use: Concomitant use of ORENCIA with other immunosuppressives [e.g., biologic disease-modifying antirheumatic drugs (bDMARDS), Janus kinase (JAK) inhibitors] is not recommended. ( 1.5 , 5.1) 1.1 Adult Rheumatoid Arthritis ORENCIA ® is indicated for the treatment of adult patients with moderately to severely active rheumatoid arthritis (RA). 1.2 Polyarticular Juvenile Idiopathic Arthritis ORENCIA is indicated for the treatment of patients 2 years of age and older with moderately to severely active polyarticular juvenile idiopathic arthritis (pJIA). 1.3 Psoriatic Arthritis ORENCIA is indicated for the treatment of patients 2 years of age and older with active psoriatic arthritis (PsA). 1.4 Prophylaxis for Acute Graft versus Host Disease ORENCIA is indicated for the prophylaxis of acute graft versus host disease (aGVHD), in combination with a calcineurin inhibitor and methotrexate, in adults and pediatric patients 2 years of age and older undergoing hematopoietic stem cell transplantation (HSCT) from a matched or 1 allele-mismatched unrelated-donor. 1.5 Limitations of Use The concomitant use of ORENCIA with other potent immunosuppressants [e.g., biologic disease-modifying antirheumatic drugs (bDMARDs), Janus kinase (JAK) inhibitors] is not recommended.

DOSAGE AND ADMINISTRATION Intravenous Use for Adult RA (2.1) and Adult PsA (2.3) • Administer at 0, 2, and 4 weeks, and every 4 weeks thereafter, as a 30-minute infusion Body Weight of Patient Dose Number of Vials Less than 60 kg 500 mg 2 60 to 100 kg 750 mg 3 More than 100 kg 1,000 mg 4 Subcutaneous Use for Adult RA (2.1) • Prior to the first subcutaneous dose, may administer an optional loading dose as a single intravenous infusion as per body weight categories above. • Administer 125 mg by subcutaneous injection once weekly (within a day of the intravenous infusion if infusion given). • Patients switching from intravenous use to subcutaneous use, administer first subcutaneous dose instead of next scheduled intravenous dose. Intravenous Use for pJIA in Pediatric Patients ≥6 Years Old (2.2) • Pediatric patients weighing <75 kg administer 10 mg/kg intravenously and those weighing ≥75 kg administer the adult intravenous dosing regimen (not to exceed a maximum dose of 1,000 mg), as a 30-minute infusion. • Subsequently administer infusions at 2 and 4 weeks and every 4 weeks thereafter. Subcutaneous Use for pJIA and PsA in Pediatric Patients ≥2 Years Old (2.2) • Administer subcutaneously without an intravenous loading dose Body Weight of Pediatric Patient Dose (once weekly) 10 kg to less than 25 kg 50 mg 25 kg to less than 50 kg 87.5 mg 50 kg or more 125 mg Subcutaneous Use for Adult PsA ( 2.3 ) • Administer 125 mg by subcutaneous injection once weekly without an intravenous loading dose. • Patients switching from intravenous use to subcutaneous use, administer first subcutaneous dose instead of next scheduled intravenous dose. Intravenous Use for Prophylaxis of aGVHD (2.4) • For patients 6 years and older, administer at a 10 mg/kg dose (maximum dose 1,000 mg) as a 60-minute infusion on the day before transplantation, followed by a dose on Day 5, 14, and 28 after transplant. • For patients 2 to less than 6 years old, administer a 15 mg/kg dose as a 60-minute infusion on the day before transplantation, followed by a 12 mg/kg dose as a 60-minute infusion on Day 5, 14, and 28 after transplant. Preparation and Administration Instructions ( 2.5 , 2.6 ) • Administer as a 30-minute intravenous infusion for RA, pJIA, and adult PsA. (2.5) • Administer as a 60-minute intravenous infusion for aGVHD prophylaxis. (2.5) • See the Full Prescribing Information for preparation and administration instructions for intravenous infusion and recommendations for subcutaneous use. (2.5, 2.6) Prepare ORENCIA using only the silicone-free disposable syringe. (2.5) 2.1 Dosage in Adult Rheumatoid Arthritis For adult patients with RA, administer as an intravenous infusion or as a subcutaneous injection. ORENCIA may be used as monotherapy or concomitantly with disease-modifying antirheumatic drugs (DMARDs) other than JAK inhibitors or bDMARDs (e.g., TNF antagonists). Intravenous Dosage Reconstitute ORENCIA lyophilized powder and administer after dilution [see Dosage and Administration (2.5) ] as a 30-minute intravenous infusion utilizing the weight range-based dosing recommended in Table 1. Following the initial intravenous infusion, administer as an intravenous infusion at 2 and 4 weeks and every 4 weeks thereafter. Table 1: Dose of ORENCIA for Intravenous Infusion in Adult RA Patients Body Weight of Adult Patient Dose Number of Vials a a Each vial provides 250 mg of abatacept for administration. Less than 60 kg 500 mg 2 60 to 100 kg 750 mg 3 More than 100 kg 1,000 mg 4 Subcutaneous Dosage Prior to the first subcutaneous dose, an optional loading dose may be administered as a single intravenous infusion (as per body weight categories in Table 1). If an intravenous loading dose is used, administer the first subcutaneous injection within one day of the infusion. Administer ORENCIA 125 mg in prefilled syringes or in ORENCIA ClickJect™ autoinjector by subcutaneous injection once weekly [see Dosage and Administration (2.6) ] . For patients switching from ORENCIA intravenous therapy to subcutaneous administration, administer the first subcutaneous dose instead of the next scheduled intravenous dose. 2.2 Dosage in Polyarticular Juvenile Idiopathic Arthritis For pediatric patients with pJIA, either administer ORENCIA as an intravenous infusion (only patients 6 years of age and older) or as a subcutaneous injection (only patients 2 years of age and older) [see Use in Specific Populations (8.4) ] . ORENCIA may be used as monotherapy or concomitantly with methotrexate. Intravenous Dosage Administer ORENCIA as a 30-minute intravenous infusion based on body weight [see Dosage and Administration (2.5) ] : • For body weight less than 75 kg, administer a dose of 10 mg/kg. • For body weight of 75 kg or greater, administer as per the recommendations in Table 1 (follow the adult intravenous dosing regimen), not to exceed a maximum dose of 1,000 mg. Following the initial intravenous infusion, administer infusions at 2 and 4 weeks and every 4 weeks thereafter. Immediately discard any unused portion in the vials. Subcutaneous Dosage Administer ORENCIA for subcutaneous injection, without an intravenous loading dose, utilizing the weight range-based dosing as recommended in Table 2 [see Dosage and Administration (2.6) ] . Subsequently administer once weekly. Table 2: Dose of ORENCIA for Subcutaneous Administration in Patients 2 Years of Age and Older with pJIA Body Weight of Pediatric Patient Dose (once weekly) 10 to less than 25 kg 50 mg 25 to less than 50 kg 87.5 mg 50 kg or more 125 mg Patients with pJIA may self-inject with ORENCIA or the patient’s caregiver may administer ORENCIA if both the healthcare practitioner and the parent/legal guardian determine it is appropriate. The ability of pediatric patients to self-inject with the autoinjector has not been tested. 2.3 Dosage in Psoriatic Arthritis Adult Patients For adult patients with psoriatic arthritis, administer as an intravenous infusion or a subcutaneous injection. ORENCIA may be used with or without non-biologic DMARDs. Intravenous Dosage Administer ORENCIA as a 30-minute intravenous infusion utilizing the weight range-based dosing specified in Table 1. Following the initial intravenous administration, administer an intravenous infusion at 2 and 4 weeks and every 4 weeks thereafter. Subcutaneous Dosage Administer 125 mg of ORENCIA subcutaneously once weekly (no intravenous loading dose is needed) [see Dosage and Administration (2.6) ] . For patients switching from ORENCIA intravenous infusions to subcutaneous administration, administer the first subcutaneous dose instead of the next scheduled intravenous dose. Pediatric Patients Administer ORENCIA as a subcutaneous injection in pediatric patients 2 years of age and older with psoriatic arthritis [see Use in Specific Populations (8.4) ] . ORENCIA may be used as monotherapy or concomitantly with methotrexate. Intravenous administration is not approved for pediatric patients with psoriatic arthritis. Subcutaneous Dosage Administer ORENCIA for subcutaneous injection weekly, utilizing the weight range-based dosage as recommended in Table 3 [see Dosage and Administration (2.6) ] . Table 3: Dose of ORENCIA for Subcutaneous Administration in Patients 2 Years of Age and Older with Psoriatic Arthritis Body Weight of Pediatric Patient Dose (once weekly) 10 to less than 25 kg 50 mg 25 to less than 50 kg 87.5 mg 50 kg or more 125 mg Pediatric patients with psoriatic arthritis may self-inject with ORENCIA or the patient’s caregiver may administer ORENCIA if both the healthcare practitioner and the parent/legal guardian determine it is appropriate. The ability of pediatric patients to self-inject with the autoinjector has not been tested. 2.4 Dosage in Prophylaxis of Acute Graft versus Host Disease in Adults and Pediatric Patients Aged 2 Years and Older Antiviral Prophylactic Treatment Before administering ORENCIA, administer recommended antiviral prophylactic treatment for Epstein-Barr Virus (EBV) reactivat

WARNINGS AND PRECAUTIONS • Concomitant use with a TNF antagonist can increase the risk of infections and serious infections. (5.1) • Hypersensitivity and anaphylaxis have occurred. (5.2) • Serious infections reported. Patients with a history of recurrent infections or underlying conditions predisposing to infections may experience more infections. Discontinue if a serious infection develops. (5.3) • Screen for latent TB infection prior to initiating therapy. Patients testing positive should be treated prior to initiating ORENCIA. (5.3) • Screen for viral hepatitis prior to initiating ORENCIA. (5.3) • Update vaccinations prior to initiating ORENCIA. Live vaccines should not be given concurrently or within 3 months of discontinuation. ORENCIA may blunt the effectiveness of some immunizations. (5.4) • COPD patients may develop more frequent respiratory adverse reactions. (5.5) • Cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) reactivation in patients treated for aGVHD prophylaxis. (5.7) 5.1 Increased Risk of Infection with Concomitant Use of TNF Antagonists, Other Biologic RA/PsA Therapy, or JAK Inhibitors In controlled clinical trials in patients with adult RA, patients receiving concomitant intravenous ORENCIA and TNF antagonist therapy experienced more infections (63% vs. 43%) and serious infections (4.4% vs. 0.8%) compared to patients treated with only TNF antagonists [see Adverse Reactions (6.1) ] . These trials failed to demonstrate an important enhancement of efficacy with concomitant administration of ORENCIA with TNF antagonists; therefore, concurrent therapy with ORENCIA and a TNF antagonist is not recommended. While transitioning from TNF antagonist therapy to ORENCIA therapy, patients should be monitored for signs of infection. Additionally, concomitant use of ORENCIA with other biologic RA/PsA therapy or JAK inhibitors is not recommended. 5.2 Hypersensitivity Reactions In clinical trials of 2688 adult RA patients treated with intravenous ORENCIA, there were two cases (<0.1%) of anaphylaxis reactions. Other reactions potentially associated with drug hypersensitivity, such as hypotension, urticaria, and dyspnea, each occurred in less than 0.9% of ORENCIA-treated patients. Of the 190 ORENCIA-treated patients in pJIA clinical trials, there was one case of a hypersensitivity reaction (0.5%) [see Adverse Reactions (6.1 )] . In postmarketing experience, fatal anaphylaxis following the first infusion of ORENCIA and life-threatening cases of angioedema have been reported. Angioedema has occurred as early as after the first dose of ORENCIA, but also has occurred with subsequent doses. Angioedema reactions have occurred within hours of administration and in some instances had a delayed onset (i.e., days). Appropriate medical support measures for the treatment of hypersensitivity reactions should be available for immediate use in the event of a reaction. If an anaphylactic or other serious allergic reaction occurs, administration of intravenous or subcutaneous ORENCIA should be stopped immediately with appropriate therapy instituted, and the use of ORENCIA should be permanently discontinued. 5.3 Infections Serious infections, including sepsis and pneumonia, have been reported in patients receiving ORENCIA (serious infections were reported in 3% and 1.9% of RA patients treated with intravenous ORENCIA and placebo, respectively) [see Adverse Reactions (6.1) ] . Some of these infections have been fatal. Many of the serious infections have occurred in patients on concomitant immunosuppressive therapy which in addition to their underlying disease, could further predispose them to infection. A higher rate of serious infections has been observed in adult RA patients treated with concurrent TNF antagonists and ORENCIA compared to those treated with ORENCIA alone [see Warnings and Precautions (5.1) ] . Healthcare providers should exercise caution when considering the use of ORENCIA in patients with a history of recurrent infections, underlying conditions which may predispose them to infections, or chronic, latent, or localized infections. Patients who develop a new infection while undergoing treatment with ORENCIA should be monitored closely. Administration of ORENCIA should be discontinued if a patient develops a serious infection. Prior to initiating ORENCIA, patients should be screened for latent tuberculosis (TB) infection according to current TB guidelines. ORENCIA has not been studied in patients with a positive TB screen, and the safety of ORENCIA in individuals with latent TB infection is unknown. Patients testing positive in TB screening should be treated by standard medical practice prior to therapy with ORENCIA. Antirheumatic therapies have been associated with hepatitis B reactivation. Therefore, screening for viral hepatitis should be performed in accordance with published guidelines before starting therapy with ORENCIA. In clinical studies with ORENCIA, patients who screened positive for hepatitis were excluded from study. 5.4 Immunizations Prior to initiating ORENCIA in pediatric and adult patients, update vaccinations in accordance with current vaccination guidelines. ORENCIA-treated patients may receive current non-live vaccines. Live vaccines should not be given concurrently with ORENCIA or within 3 months after discontinuation. No data are available on the secondary transmission of infection from persons receiving live vaccines to patients receiving ORENCIA. In addition, there are clinical considerations for administering live vaccines to infants who were exposed to ORENCIA while in utero [see Use in Specific Populations (8.1) ] . Based on its mechanism of action, ORENCIA may blunt the effectiveness of some immunizations. 5.5 Increased Risk of Adverse Reactions When Used in Patients with Chronic Obstructive Pulmonary Disease (COPD) In Study V, adult COPD patients treated with ORENCIA for RA developed adverse reactions more frequently than those treated with placebo, including COPD exacerbations, cough, rhonchi, and dyspnea. A greater percentage of patients treated with ORENCIA developed a serious adverse event compared to patients treated with placebo (27% vs 6%) [see Clinical Studies (14.1) and Adverse Reactions (6.1) ] . Use of ORENCIA in patients with COPD should be undertaken with caution and such patients should be monitored for worsening of their respiratory status. 5.6 Immunosuppression The possibility exists for drugs inhibiting T-cell activation, including ORENCIA, to affect host defenses against infections and malignancies since T cells mediate cellular immune responses. In clinical trials in patients with adult RA, a higher rate of infections was seen in ORENCIA-treated patients compared to placebo-treated patients [see Warnings and Precautions (5.3) and Adverse Reactions (6.1) ] . The impact of treatment with ORENCIA on the development and course of malignancies is not fully understood [see Adverse Reactions (6.1) ] . There have been reports of malignancies, including skin cancer in patients receiving ORENCIA [see Adverse Reactions (6.3) ] . Periodic skin examinations are recommended for all ORENCIA-treated patients, particularly those with risk factors for skin cancer. 5.7 Cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) Reactivation in aGVHD Prophylaxis after Hematopoietic Stem Cell Transplant (HSCT) Post-Transplant Lymphoproliferative Disorder (PTLD) occurred in patients who received ORENCIA for aGVHD prophylaxis during unrelated HSCT. Of 116 patients who received ORENCIA, 4 patients (3.4%) experienced PTLD. All the PTLD events were associated with Epstein-Barr virus (EBV) infection. Three of the four patients were EBV serology positive at baseline; one patient had negative baseline EBV serology with donor EBV serology unknown. Three of the 4 patients discontinued acyclovir prophylaxis at day 30 post-transplant. The range of time to onset of the events was 49 to 89 days post-transplant. Monitor patients for EBV reactivat

CONTRAINDICATIONS None. None. (4)

DRUG INTERACTIONS 7.1 Immunosuppressants Concomitant administration of a TNF antagonist with ORENCIA has been associated with an increased risk of serious infections and no significant additional efficacy over use of the TNF antagonists alone. Concurrent therapy with ORENCIA and TNF antagonists is not recommended [see Warnings and Precautions (5.1) ]. There is insufficient experience to assess the safety and efficacy of ORENCIA administered concurrently with other biologic RA therapy, such as anakinra, or other biologic PsA therapy, and JAK inhibitors and therefore such use is not recommended. [see Warnings and Precautions (5.1) ] . 7.2 Blood Glucose Testing Parenteral drug products containing maltose can interfere with the readings of blood glucose monitors that use test strips with glucose dehydrogenase pyrroloquinoline quinone (GDH-PQQ). The GDH-PQQ based glucose monitoring systems may react with the maltose present in ORENCIA for intravenous administration, resulting in falsely elevated blood glucose readings on the day of infusion. When receiving intravenous ORENCIA, patients that require blood glucose monitoring should be advised to consider methods that do not react with maltose, such as those based on glucose dehydrogenase nicotine adenine dinucleotide (GDH-NAD), glucose oxidase, or glucose hexokinase test methods. ORENCIA for subcutaneous administration does not contain maltose; therefore, patients do not need to alter their glucose monitoring.

ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: • Increased Risk of Infection with Concomitant Use with TNF Antagonists, Other Biologic RA/PsA Therapy, or JAK Inhibitors [see Warnings and Precautions (5.1) ] • Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] • Infections [see Warnings and Precautions (5.3) ] • Increased Risk of Adverse Reactions When Used in Patients with Chronic Obstructive Pulmonary Disease (COPD) [see Warnings and Precautions (5.5) ] • Immunosuppression [see Warnings and Precautions (5.6) ] • Cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) Reactivation in aGVHD Prophylaxis after Hematopoietic Stem Cell Transplant (HSCT) [see Warnings and Precautions (5.7) ] • Most common adverse events (≥10%) in RA are headache, upper respiratory tract infection, nasopharyngitis, and nausea. (6.1) • Most common adverse reactions (≥10%) in prophylaxis of aGVHD are anemia, hypertension, CMV reactivation/CMV infection, pyrexia, pneumonia, epistaxis, CD4 lymphocytes decreased, hypermagnesemia, and acute kidney injury. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact Bristol-Myers Squibb at 1-800-721-5072 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying and controlled conditions, adverse reaction rates observed in clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not predict the rates observed in a broader patient population in clinical practice. Adverse Reactions in Adult Patients with RA Adverse Reactions in Adult Patients with RA Treated with Intravenous ORENCIA The data from placebo-controlled studies described herein reflect exposure to ORENCIA administered intravenously in patients with active RA (1955 patients with ORENCIA, 989 with placebo) (Studies I through VI) [see Clinical Studies (14.1) ] . The studies had either a double-blind, placebo-controlled period of 6 months (258 patients with ORENCIA, 133 with placebo) or 1 year (1697 patients with ORENCIA, 856 with placebo). A subset of these patients received concomitant biologic DMARD therapy, such as a TNF antagonist (204 patients with ORENCIA, 134 with placebo). The concomitant use of ORENCIA with a TNF antagonist is not recommended [see Indications and Usage (1.5) ] . The majority of patients in RA clinical studies received one or more of the following concomitant medications with ORENCIA: methotrexate, nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, TNF antagonist, azathioprine, chloroquine, gold, hydroxychloroquine, leflunomide, sulfasalazine, and anakinra. The most serious adverse reactions were serious infections and malignancies. The most commonly reported adverse events (occurring in ≥10% of patients treated with ORENCIA) were headache, upper respiratory tract infection, nasopharyngitis, and nausea. The adverse reactions most frequently resulting in clinical intervention (interruption or discontinuation of ORENCIA) were due to infection. The most frequently reported infections resulting in dose interruption were upper respiratory tract infection (1%), bronchitis (0.7%), and herpes zoster (0.7%). The most frequent infections resulting in discontinuation were pneumonia (0.2%), localized infection (0.2%), and bronchitis (0.1%). Most Common Adverse Reactions in Adult Patients with RA Treated with Intravenous ORENCIA Adverse reactions occurring in 3% or more of patients and at least 1% more frequently in ORENCIA-treated patients (intravenous) during placebo-controlled RA studies are summarized in Table 4. Table 4: Most Common Adverse Reactions* During Placebo-Controlled RA Studies of Intravenous ORENCIA Intravenous ORENCIA (n=1955) a Placebo (n=989) b * Occurred in ≥3% patients and >1% more frequently in ORENCIA-treated patients. a Includes 204 patients on concomitant biologic DMARDs (adalimumab, anakinra, etanercept, or infliximab). b Includes 134 patients on concomitant biologic DMARDs (adalimumab, anakinra, etanercept, or infliximab). Headache 18% 13% Nasopharyngitis 12% 9% Dizziness 9% 7% Cough 8% 7% Back pain 7% 6% Hypertension 7% 4% Dyspepsia 6% 4% Urinary tract infection 6% 5% Rash 4% 3% Pain in extremity 3% 2% Infections in Adult Patients with RA Treated with Intravenous ORENCIA In the placebo-controlled trials in patients with RA, infections were reported in 54% of intravenous ORENCIA-treated patients and 48% of placebo-treated patients. The most commonly reported infections (reported in 5%-13% of patients) were upper respiratory tract infection, nasopharyngitis, sinusitis, urinary tract infection, influenza, and bronchitis. Other infections reported in fewer than 5% of patients at a higher frequency (>0.5%) with ORENCIA compared to placebo, were rhinitis, herpes simplex, and pneumonia [see Warnings and Precautions (5.3) ] . Serious infections were reported in 3% of patients treated with ORENCIA and 1.9% of patients treated with placebo. The most common (0.2%-0.5%) serious infections reported with ORENCIA were pneumonia, cellulitis, urinary tract infection, bronchitis, diverticulitis, and acute pyelonephritis [see Warnings and Precautions (5.3) ] . Malignancies in Adult Patients with RA Treated with Intravenous ORENCIA In the placebo-controlled portions of the clinical trials (1955 patients treated for RA with ORENCIA for a median of 12 months), the overall frequencies of malignancies were similar in the ORENCIA- and placebo-treated patients (1.3% and 1.1%, respectively). However, more cases of lung cancer were observed in ORENCIA-treated patients (4 cases, 0.2%) than placebo-treated patients (0 cases, 0%). In the cumulative intravenous ORENCIA clinical trials in patients with RA (placebo-controlled and uncontrolled, open-label) a total of 8 cases of lung cancer (0.21 cases per 100 patient-years) and 4 lymphomas (0.10 cases per 100 patient-years) were observed in 2688 patients (3827 patient-years). The rate observed for lymphoma is approximately 3.5-fold higher than expected in an age- and gender-matched general population based on the National Cancer Institute's Surveillance, Epidemiology, and End Results Database. Patients with RA, particularly those with highly active disease, are at a higher risk for the development of lymphoma. Other malignancies included skin, breast, bile duct, bladder, cervical, endometrial, lymphoma, melanoma, myelodysplastic syndrome, ovarian, prostate, renal, thyroid, and uterine cancers [see Warnings and Precautions (5.6) ] . The potential role of ORENCIA in the development of malignancies in humans is unknown. Infusion-Related Reactions and Hypersensitivity Reactions in Adult Patients with RA Treated with Intravenous ORENCIA Acute infusion-related events (adverse reactions occurring within 1 hour of the start of the infusion) in Studies III, IV, and V [see Clinical Studies (14.1) ] were more common in the ORENCIA-treated patients than the placebo patients (9% for ORENCIA, 6% for placebo). The most frequently reported events (1%-2%) were dizziness, headache, and hypertension. Acute infusion-related events that were reported in >0.1% and ≤1% of patients treated with ORENCIA included cardiopulmonary symptoms, such as hypotension, increased blood pressure, and dyspnea; other symptoms included nausea, flushing, urticaria, cough, hypersensitivity, pruritus, rash, and wheezing. Most of these reactions were mild (68%) to moderate (28%). Fewer than 1% of ORENCIA-treated patients discontinued due to an acute infusion-related event. In controlled trials, 6 ORENCIA-treated patients compared to 2 placebo-treated patients discontinued study treatment due to acute infusion-related events. In clinical trials of 2688 adult RA patients treated with intravenous ORENCIA, there were two cases (<0.1%) of anaphylaxis. Other reactions potentially associated with drug hypersensitivity, such as hypotension, urticaria, and d

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. Activated T lymphocytes are implicated in the pathogenesis of RA, pJIA and PsA and are found in the synovium of patients with RA, pJIA and PsA. In vitro , abatacept decreases T-cell proliferation and inhibits the production of the cytokines TNF alpha (TNFα), 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 exerts its clinical effects is unknown.