A Study to Assess the Safety and Pharmacokinetics of INCB123667 When Administered Orally to Adult Participants With Severe Renal Impairment or End Stage Renal Disease

• INCB123667 (Drug): Group 1: Single dose administered orally. Group 2: Two single doses administered orally.

Primary outcomes

• PK for plasma INCB123667: Cmax [Up to approximately 3 months]: Defined as the maximum plasma concentration.
• PK for plasma INCB123667: AUCt [Up to approximately 3 months]: Defined as area under the concentration-time curve from time zero to time of last quantifiable concentration.
• PK for plasma INCB123667: AUC∞ [Up to approximately 3 months]: Defined as area under the single-dose concentration-time curve extrapolated to time of infinity.

Secondary outcomes

• Number of Treatment-Emergent Adverse Events (TEAEs) [Up to approximately 3.5 months]: Adverse events reported for the first time or worsening of a pre-existing event, occurring after study drug/treatment.

Sex: All, ages: 18 Years to 85 Years

Inclusion Criteria:

* Aged 18 to 85 years, inclusive, at the time of signing the ICF.
* Severe renal impairment or ESRD based on CKD-EPI.
* Body mass index of 18.0 to 43.0 kg/m2 (inclusive).
* Willingness to avoid pregnancy or fathering children.

Exclusion Criteria:

* Participants who have a current, functioning organ transplant or are on the national transplant list and expected to receive a transplant within 3 months.
* Participants with laboratory values outside the accepted range for participants with severe renal impairment or ESRD at screening. Participants with out-of-range values will be assessed by the investigator or designee for eligibility.
* Tobacco or nicotine-containing product use of > 10 cigarettes per day within 1 month before screening.
* Participants who had a change in disease status within 30 days before screening, as documented by the participant's medical history, that is deemed clinically significant by the investigator.
* Participants who have a history of paracentesis within 3 months prior to check-in.
* Participants who required new medication or an increase in dose for renal disease within 3 months prior to check-in.
* Participants who have a history of unstable diabetes mellitus (as evidenced by hemoglobin A1c ≥ 10.0%). Medications for treatment of diabetes mellitus must be reviewed and approved by the investigator and medical monitor.
* Participants who had esophageal banding within 3 months prior to check-in or required any other treatment for gastrointestinal bleeding within 6 months prior to check-in.

Other protocol-defined Inclusion/Exclusion Criteria may apply.

• Incyte Medical Monitor, Study director, Incyte Corporation