How Emerging Oral Therapies Target HS Inflammation

In "How Emerging Oral Therapies Target HS Inflammation," the panel explores how JAK and BTK inhibitors interrupt inflammation from inside the cell.

Chao introduces three emerging oral therapies now in Phase 3 trials for HS: povorcitinib, upadacitinib, and remibrutinib. Dr. Bush explains their mechanisms for the audience. Unlike IL-17 inhibitors, which work outside the cell to block cytokines from docking onto their receptors, JAK inhibitors act inside the cell. Once a cytokine activates its receptor, the JAK-STAT pathway turns on and signals the nucleus to switch on inflammatory genes. JAK inhibitors interrupt that signal before it reaches the nucleus, which Dr. Bush likens to cutting off a message before it can be delivered. BTK inhibitors, such as remibrutinib, act further downstream, inside the B cells and plasma cells found within HS draining tunnels, blocking the chronic inflammatory signaling that keeps those cells active. Dr. Bush is enthusiastic that both drug classes target different points along the inflammatory pathway, including the draining tunnels that remain especially difficult to treat with current options. Discussing what oral therapies could mean for patients, Dr. Bush says having an oral alternative to injections is genuinely valuable, even as some patients grow more comfortable with injections over time. Because HS is so heterogeneous, with one drug working well for one patient and not another, she hopes new molecular targets, and eventually combinations of them, will fill gaps left by current therapies. She stresses that no two HS patients are truly alike, since clinicians still cannot identify exactly what is driving inflammation in each individual case. Chao adds that HS is experiencing a simultaneous oral-therapy revolution alongside psoriasis and psoriatic arthritis, a development he did not anticipate, and calls the expanding pipeline especially meaningful for a disease that has historically offered patients very limited treatment choices.

The next episode in this series, "Efficacy and Safety Data for Emerging Oral HS Agents," presents the clinical trial data behind these emerging oral agents.