Phase 3

Photo of scientist with petri dish and syringe


Reported data suggest that IL-1α and IL-1β may play roles in RP and other autoinflammatory diseases. We have completed an open-label Phase 2 clinical trial of rilonacept in different RP populations. Interim data from all symptomatic RP and postpericardiotomy syndrome (PPS) subjects showed reductions in both C-reactive protein (CRP) and reported pain as well as improvement in quality-of-life scores. Additionally, CRP and reported pain remained low for all asymptomatic RP and PPS subjects.

Status: Phase 3

We are currently enrolling a pivotal, global Phase 3 clinical trial in RP, named RHAPSODY.

RHAPSODY is a double-blind, placebo-controlled, randomized-withdrawal (RW) design study with open-label extension in subjects with symptomatic RP. After a run-in period with stabilization and tapering of background medications to rilonacept, clinical responders will be randomized to continued rilonacept or placebo injected subcutaneously weekly during the 24-week RW period. The primary efficacy endpoint is time to first adjudicated pericarditis recurrence in the RW period. Topline data are expected in the second half of 2020.

Unmet Need

We are not aware of any current therapies approved by the FDA for the treatment of RP.

  • We believe RP presents a significant clinical and humanistic burden and imposes a significant financial burden on the healthcare system.
  • A patient’s initial acute episode of pericarditis is typically treated with either over-the-counter or prescription nonsteroidal anti-inflammatory drugs (NSAIDs) or colchicine, both of which are used off-label. Recurrent episodes are treated in a similar manner or by adding systemic corticosteroids, which are also used off-label.
  • We believe the greatest demand in the market is not just for a product that treats the symptoms of a pericarditis recurrence but for one that also reduces the risk of future recurrences.
  • Within the estimated diagnosed and treated RP population of 40,000, we believe that there are initially ~14,000 patients who may benefit from rilonacept – ~3,000 refractory, ~6,000 poorly controlled or steroid dependent, and ~5,000 steroid intolerant refractory to NSAIDs and colchicine.
  • Refractory and steroid-dependent patients have the highest recurrence burden, with 30% to 40% of patients experiencing greater than 2 episodes per year.
    • They also have a higher incidence of severe complications, such as cardiac tamponade and constrictive pericarditis, often use opioids to manage their pain, and deal with anxiety and depression due to the unpredictability and severity of recurrences.

Stethoscope over chest

Explore Our Pipeline

We are intent on developing an array of innovative therapies that answer the many and varied needs of patients.