A Study To Estimate The Amount Of CP-690,550 (Study Drug) That Is Absorbed Into The Blood Of Healthy Subjects Following Oral Administration Of CP-690,550 In Tablet Form

In this study, a 10 mg dose of CP-690,550 will be given to study subjects on two separate occasions by two different routes of administration: One time by mouth in tablet form and one time by vein (intravenous form). The amount of CP-690,550 available in the blood following administration by vein will be measured and is expected to reflect the maximum amount possible for the 10 mg CP-690,550 dose. The amount of CP-690,550 that is achieved in the blood following oral tablet administration will also be measured and compared to that achieved following administration by vein in order to estimate how much of the maximum amount possible is actually absorbed into the blood following administration by mouth as a tablet.