A single-center, open-label, randomized study with a screening period of up to 21 days. Following that, eligible men and women will receive 50 mg of etanercept subcutaneously in the thigh to compare injection by auto-injection device to manual injection (each injection separated by 28 days)

A single-center, open-label, 2-period, 2-sequence, 2-treatment, randomized, crossover study. After a screening period of up to 21 days before dosing, 36 eligible men and women will be assigned to receive a 50-mg subcutaneous (SC) dose of etanercept administered by each of 2 methods of injection (Treatment A: administration by auto-injector device; and Treatment B: administration by manual injection) on separate occasions in an order determined by a randomization list (randomized 1:1 to sequence). Treatment administrations will be separated by a minimum of 28 days (maximum of 36 days). Subjects will be required to remain resident during the 72-hours after dosing in each period.

Inclusion Criteria:

• Men and women between the age of 18 and 45 years, inclusive at the time of screening
• Body mass index (BMI) between 19 and 30 kg/m2, inclusive at the time of screening
• Absence of clinically significant physical examination findings as determined by the investigator and free of any clinically significant disease or condition that requires care by a physician that would interfere with the study evaluation or procedures
• 12-lead ECG (reporting ventricular rate and PR, QRS, QT and QTc intervals) within normal limits or clinically acceptable to the investigator
• Negative human immunodeficiency virus (HIV) antibody, hepatitis B surface antigen (HBsAg), and hepatitis C antibody (HepCAb) status at the time of screening
• Negative pregnancy test for all women at screening and the day before dosing
• Willing to reside in the research facility for 3 consecutive nights, on two occasions, and willing to return to research facility for scheduled follow-up visits
• Before any study specific procedures or administration of study medication, the subject must sign the Institutional Review Board (IRB)-approved informed consent form

Exclusion Criteria:

• Unstable medical condition, defined as having been hospitalized within 30 days, myocardial infarction within 6 months, major surgery within 6 months, or a seizure within 12 months of study day 1, or otherwise unstable in the judgment of the investigator (i.e., at risk of complications or adverse events unrelated to study participation)
• Clinically significant abnormality in chemistry, hematology, or urinalysis parameters performed at screening as determined by the investigator
• Current active infection, including chronic or localized infection or history of recurring infections with underlying condition that may predispose one to infection (e.g., diabetes)
• Known history of active tuberculosis
• Donated blood or blood products within 12 weeks before day -1, or a total of 1500 mL within 1 year before day -1
• Known hypersensitivity to etanercept or any excipients
• Use of any prescription or over-the-counter medication within 7 days before day -1 without the approval of the investigator (with the exception of vitamins, topical medications, contraceptive medications, or hormonal replacement therapy in postmenopausal women)
• Consumption of alcohol within 48 hours before dosing
• Known history of drug or alcohol abuse within 1 year of screening
• Positive urine screen for alcohol and/or potential drugs of abuse, at screening, and the day before dosing
• Smoked more than 10 cigarettes per day within the 12 months before day -1
• Women who are nursing or lactating
• Unwilling or unable to practice an adequate barrier method of contraception (e.g., condom, barrier method contraceptive with spermicide, IUD, etc.), as determined by the investigator, for the duration of the study
• Use of an investigational agent, drug, and/or device within 30 days of screening
• Any other condition that might reduce the chance of obtaining data (e.g., known poor compliance) required by the protocol or that might compromise the ability to give informed consent