A Study to Evaluate the Safety, Tolerability and Pharmacokinetics of INCB054707

Inclusion criteria

• Male healthy Japanese adult participants aged 20 to 55 years with a minimum weight of 48 kg.
• Body mass index between 18.0 and 30.5 kg/m2.
• No clinically significant findings in screening evaluations.
• Ability to swallow and retain oral medication.
• Willingness to avoid fathering children

Exclusion criteria

• History of clinically significant cardiovascular, respiratory, renal, gastrointestinal, endocrine, hematopoietic, psychiatric, and/or neurological disease.
• History of rheumatologic/autoimmune disorders, except for minor eczema and rosacea.
• Resting pulse < 40 bpm or > 100 bpm, confirmed by repeat testing at screening.
• History or presence of an abnormal ECG before initial dose administration that, in the investigator's opinion, is clinically significant.
• Presence of a malabsorption syndrome possibly affecting drug absorption (eg, Crohn's disease or chronic pancreatitis).
• Hemoglobin, WBC, platelet, or ANC that is out of the laboratory's range unless considered clinically insignificant by the investigator at screening or check-in.
• History of malignancy within 5 years of screening, with the exception of cured basal cell or squamous cell carcinoma of the skin.
• Current or recent (within 6 months of screening) clinically significant gastrointestinal disease or surgery (including cholecystectomy, excluding appendectomy) that could affect the absorption of study drug.
• Any major surgery within 6 months of screening.
• Donation of blood to a blood bank or in a clinical study (except a screening visit) within 4 weeks of screening (within 2 weeks for plasma donation).
• Blood transfusion within 4 weeks of check-in.
• Chronic or current active infectious disease requiring systemic antibiotic, antifungal, or antiviral treatment
• Positive test for HIV and known active HBV or HCV infection or risk of reactivation of HBV or HCV.
• History of alcoholism within 3 months of screening.
• Positive breath or urine test for ethanol or positive urine screen for drugs of abuse that are not otherwise explained by permitted concomitant medications or diet.
• Current treatment or treatment within 30 days or 5 half-lives (whichever is longer) before the first dose of study drug with another investigational medication or current enrollment in another investigational drug study.
• Current treatment or treatment within 30 days or 5 half-lives (whichever is longer) before the first dose of study drug with an inducer or inhibitor of CYP3A4, P-gp, or BCRP
• Current use of prohibited medication
• Consumption of Seville oranges, grapefruit or grapefruit juice, pomelos, exotic citrus fruits, grapefruit hybrids, or fruit juices within 72 hours before the first dose of study drug.
• History of any significant drug allergy (such as anaphylaxis or hepatotoxicity) deemed clinically relevant by the investigator.
• Known hypersensitivity or severe reaction to INCB054707 or any excipients of INCB054707
• Inability to undergo venipuncture or tolerate venous access.
• Inability or unlikeliness of the participant to comply with the dose schedule and study evaluations, in the opinion of the investigator.
• History of tobacco- or nicotine-containing product use within 1 month of screening.
• Use of prescription drugs within 14 days of study drug administration or nonprescription medications/products within 7 days of study drug administration.
• Any condition that would, in the investigator's judgment, interfere with full participation in the study.
• Positive syphilis test.