Study to Assess Adverse Events and How Oral ABBV-990 Moves Through the Body of Adult Healthy Participants

This study will assess how safe ABBV-990 is and how ABBV-990 moves through the body of adult healthy participants. Adverse Events will be assessed. ABBV-990 is an investigational drug being developed for the treatment of SARS-CoV-2 infections. Participants are randomly assigned to one of the 5 treatment groups. Each group receives different treatment. There is 1 in 4 chance that participants are assigned to placebo. Approximately 40 adult healthy volunteers will be enrolled in a single site in the United States. Participants will receive oral tablet of ABBV-990 or matching placebo on Day 1 and followed for approximately 30 days. Participants will be confined for 5 days. Adverse Events and blood tests will be performed.