Hidradenitis suppurativa, or HS, is a long-lasting skin disease that causes painful lumps, abscesses, and scars in areas like underarms, groin, and thighs. This study is looking at a new medicine called lutikizumab to see if it can help people with moderate to severe HS. People joining the study will get injections under the skin either of lutikizumab or a placebo (a fake medicine) and will be checked for side effects and improvements. There are two parts to the study. In the first part, injections are given every week for 16 weeks. In the second part, the frequency varies depending on which group you're in, continuing for up to 36 weeks. The study will involve regular visits to a hospital or clinic for check-ups, blood tests, and answering questions about how you're doing. It's important to know that this study might require more time and effort than usual care. About 1280 people will join the study at 275 places around the world.

• The study lasts for up to 52 weeks.
• Participants will have regular hospital or clinic visits.
• The study may require more effort than standard care.