A Study to Understand the Effect of Tablet Formulation and Food on PF-06821497 in Healthy Adult Participants.

The purpose of this study is to understand the effect of tablet formulation and presence of food on the study medicine PF-06821497 in healthy adult participants. The study is seeking for male and female participants who: * Are 18 years of age or more. * Are confirmed to be healthy after performing some medical and physical tests. * Weigh more than 50kgs of body weight and have a body mass index of 17 and a half kg per meter squared or more. The study consists of two parts. In each part of the study, the selected participants will take part in 3 study periods to receive 3 different treatments which are randomly assigned. There will also be a 5-day gap between each study period. This is done so that the medicine is passed out of the body before the start of next study period. Each treatment consists of a single dose of PF-06821497. The treatments differ by tablet formulation and/or whether the medicine is to be given with food or without food conditions. How the medicine is processed in the body will be studied after giving the medicines to the participants. This will be done by collecting blood samples after each administration. The results will be used to see the effect of tablet formulation and presence of food on the amount of PF-06821497 available in the blood of the participants. In each part, participants will be on the study up to 10 weeks, including the screening and follow-up periods.