A Study Evaluating Relative Bioavailability of an Oral Suspension of Abrocitinib and Effect of an Acid Reducing Agent on the Bioavailability of Abrocitinib and Assessing the Taste of Abrocitinib Oral Formulations.

This study consists of 2 parts: Part A is to estimate the relative bioavailability of a single 200 mg dose of abrocitinib oral suspension (Test formulation) compared to the commercial abrocitinib tablet (200 mg) (Reference formulation). The effect of an acid-reducing agent on the pharmacokinetics of abrocitinib and its metabolites will also be evaluated by administering abrocitinib 200 mg commercial tablet with or without famotidine 40 mg, as an acid-reducing agent. Part B is to assess the taste and palatability of six different abrocitinib oral suspension formulations. Additionally, the safety and tolerability of abrocitinib tablet (in Part A) and abrocitinib oral suspension formulations (in Part B) will be assessed when given with or without famotidine 40 mg once daily.