KESETT is a study to see if adding a medicine called ketamine (KET) to another medicine, levetiracetam (LEV), helps control a kind of seizure called status epilepticus (SE) better than using LEV alone. SE is a serious condition where seizures last too long. The study is "blinded," meaning neither the doctors nor the patients know which treatment is given, ensuring fairness. The main goal is to stop SE within 15 minutes of starting the medicine and to maintain this control for at least 60 minutes without needing more seizure medicine. Secondary goals include making sure the treatments are safe and checking their effectiveness, including in children.

• The study involves up to 770 participants and uses a special method to assign treatments over time.
• To join, you must be 1 year or older and have had specific kinds of seizures recently.
• The study excludes people with certain medical conditions or who have taken specific other medicines.