A Study to Learn About How Different Forms of the Study Medicine Called Ritlecitinib Pass the Intestines of Healthy Male Adults When Taken With or Without Food

The purpose of this study is to learn about how different forms of the study medicine called ritlecitinib pass the intestines of healthy male adults when taken with or without food. This study is seeking healthy participants who have: * Aged 18 years or older; * male who are healthy as determined by medical assessment; * BMI of 16-32 kg/m2, and a total body weight \>45 kg (99 lb). All participants in this study will receive a ritlecitinib oral dose in two different forms (solution without food, capsule with or without food). The study will take up to 3 months, including the screening period and follow-up phone call. Participants will have to stay at the study clinic for at least 11 days. There will be 3 periods in total, and a washout period of at least 3 days between dosings in Period 1 and Period 2, and at least 7 days between dosings in Period 2 and Period 3 for this study. On day 1 of each period, participants will take one form of Riltecitinib without food for the first two periods and with food for the last period. Participants will have blood samples taken both before and after taking ritlecitinib. A follow-up phone call will be made at 28 to 35 days after the last study period.