The purpose of this study is to assess how safe, effective, and tolerable ABBV-547 is in adult participants in the United States and Japan. There will be 2 parts to this study. In Part 1, participants are placed in one of 3 groups where they will receive ABBV-547 at different doses or placebo. There is a 1 in 4 chance participants will receive placebo. In Part 2, participants are placed in one of 3 groups where they will receive ABBV-547 at different doses or placebo. There is a 1 in 7 chance participants will receive placebo. Approximately 87 adult participants will be enrolled at approximately 21 sites in the United States and Japan. Participants will be administered one dose of ABBV-547 or placebo. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires.