This clinical trial is focused on studying a group of conditions known as neutropenias. Neutropenias are disorders where the body has a lower than normal number of a type of white blood cell called neutrophils, which are important for fighting infections. The study is particularly interested in people with chronic forms of these conditions, which can be either congenital (present from birth) or acquired later in life. These conditions can lead to frequent and serious infections.

The treatment being tested in this study is a medication called mavorixafor, which is taken as a capsule by mouth. The purpose of the study is to evaluate how effective mavorixafor is in reducing the rate of infections and improving the levels of neutrophils in the blood. Participants in the study will be randomly assigned to receive either mavorixafor or a placebo, which looks like the medication but does not contain the active ingredient. The study will last for about a year, during which participants will have regular check-ups to monitor their health and the effects of the treatment.

Throughout the study, participants will be closely monitored for any changes in their condition, including the frequency and severity of infections. The study aims to provide valuable information on the safety and tolerability of mavorixafor for people with chronic neutropenia. This research could potentially lead to new treatment options for managing these challenging conditions.