This open-label, multi-center study will compare the bioavailability of RoActemra/Actemra (tocilizumab) administration by auto-injector versus pre-filled syringe in healthy volunteers. Healthy volunteers will receive a single dose of RoActemra/Actemra (tocilizumab). The anticipated time of study duration is 28 days.

Inclusion Criteria:

• Healthy volunteers, age 18 to 65 years inclusive
• Intact normal skin without potentially obscuring tattoos, pigmentation, lesion in the area for intended injection
• A body mass index (BMI) between 18 to 32 kg/m2 inclusive

Exclusion Criteria:

• Volunteers with any known active current or history of recurrent bacterial, viral, fungal, mycobacterial or other infections
• A history of clinically significant gastrointestinal, renal, hepatic, cardiovascular, or allergic disease