Conditions: Healthy
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 35
Healthy volunteers: yes

Brief summary:
The purposes of this study are to determine:

* The effect of single increasing doses of the study drug, abemaciclib, on healthy participants.
* The relationship between the amount of abemaciclib and the electrical tracing of the heart rhythm when abemaciclib is given.
* How much abemaciclib is found in the bloodstream and how long the body takes to get rid of it.

Information about any side effects that occur will be collected. The study will enroll two groups (cohorts) of participants. Each group will complete 4 study periods. This study is expected to last about 3 months. Screening may occur up to 28 days prior to enrollment. All participants will undergo a follow-up assessment approximately 21 days after administration of their final dose of study drug.

Detailed description:

Arms:
arm 1: 200 - 600 mg single increasing oral dose of abemaciclib on Day 1 of up to 3 study periods. arm 2: Single oral dose of placebo on Day 1 of 1 study period. arm 3: Cohort 2, only. 8 mg Loperamide given orally once in 1 of 4 study periods. arm 4: Cohort 2, only. 8 mg Loperamide co-administered with abemaciclib given orally once in up to 1 of 4 study periods. arm 5: Cohort 2, only. 8 mg Loperamide co-administered with placebo given orally once in up to 1 of 4 study periods.

Interventions: intervention 1: Abemaciclib intervention 2: Placebo intervention 3: Loperamide
Intervention descriptions: intervention 1: Administered orally intervention 2: Administered orally intervention 3: Administered orally

Protocol document: