A Phase 2/3 Study in Adult and Adolescent Participants With SCD

To join this study, you need to have sickle cell disease. Your doctors will check if your health is stable, especially your blood counts. If you're already taking other medicines for sickle cell, like hydroxyurea or L-glutamine, your dose must have been steady for at least 3 months and not expected to change during the study.

For the main part of the study, you'll need to be between 12 and 65 years old. Also, you must have had between 2 and 10 painful crises (called vaso-occlusive crises or VOCs) in the 12 months before the study starts. Having too many or too few crises might mean you can't join.

There are also some reasons why you might not be able to join. For example, if you've had more than 10 painful crises in the last year, or if you're pregnant or breastfeeding. Also, if you regularly need blood transfusions, or had one within the last 3 months, you wouldn't be able to participate. If you've been in hospital recently for a sickle cell crisis, you'd need to wait until you've fully recovered before considering the study.

If you decide to take part, you'll be given the study medicine, osivelotor, to take by mouth. The study involves regular visits to the clinic where doctors and nurses will check on your health. This will include physical exams, blood tests, and asking questions about how you're feeling and any symptoms you might have. The study is divided into parts. The first part helps find the right dose, and then others compare the medicine to a dummy pill or look at long-term effects.

The second main part of the study where the medicine is compared to a dummy pill will last for about 48 weeks (around 11 months). If you complete this part, there's an optional extension that allows you to continue taking the medicine and being monitored for a longer period. Throughout your time in the study, you'll have scheduled appointments to make sure everything is going well and to collect important health information.