An innovative approach with breakthrough results1

Targeted Mechanism
ARCALYST specifically targets interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β).1
Targeting these key cytokines blocks the underlying mechanism that drives inflammation in recurrent pericarditis.1
ARCALYST blocks IL-1 signaling by acting as a soluble decoy receptor that binds both IL-1α and IL-1β and prevents their interaction with cell surface receptors, thus disrupting the cycle of autoinflammation that drives recurrent pericarditis.
Watch the video to learn the key role of IL-1 and view about the ARCALYST mechanism of action.
PHASE 3 RHAPSODY
RHAPSODY is a Phase 3 clinical trial designed to study ARCALYST in recurrent pericarditis.1
See below for the full design of the Phase 3, global, multicenter,
double-blind, placebo-controlled, randomized withdrawal trial
with an open-label extension.1,2
Run-In Period
12 Weeks
Initiation of ARCALYST and transition to monotherapy
GOAL
Assess time to treatment response and time to ARCALYST monotherapy
SECONDARY ENDPOINT
Proportion of patients achieving a treatment response
Upon enrollment patients were:
- Started on a loading dose of ARCALYST
- Tapered off standard therapies to achieve ARCALYST monotherapy
- Standard therapies included nonsteroidal anti-inflammatory drugs (NSAIDs), colchicine, and corticosteroids (alone or in combination)
- Monotherapy was achieved in 7.9 weeks
The number of patients taking standard therapies at enrollment were as follows3:
- NSAIDs: 58
- Colchicine: 69
- Corticosteroids: 42
Randomized Withdrawal
Event Driven by Adjudicated Recurrences
Treatment with ARCALYST or placebo
Goal
Assess reduction in risk of pericarditis recurrence
PRIMARY TRIAL ENDPOINT
Time to pericarditis recurrence
Major SECONDARY EFFICACY ENDPOINTS (week 16)
- Proportion of patients maintaining clinical response
- Percentage of days with no or minimal pericarditis pain
After randomization, patients were treated with double-blind ARCALYST or placebo in a 1:1 ratio until recurrence of pericarditis or until the end of the study.
- Blinded ARCALYST
- 160 mg subcutaneous injection weekly (adults ≥18 years)
- 2.2 mg/kg subcutaneous injection weekly (adolescents 12-17 years)
- Blinded placebo subcutaneous injection weekly
- Eligible patients experiencing a recurrence received bailout ARCALYST
Long-Term Extension
24 Months
Long-term management with ARCALYST
GOAL
Assess treatment up to 2 years
When the event-driven portion of the trial closed, eligible patients could participate in the open-label long-term extension (LTE) treatment period.
All eligible patients received open-label ARCALYST during the LTE treatment period.
Key inclusion criteria at screening
Key inclusion criteria at screening1
- Male or female aged 12 years or older
- Diagnosed with recurrent pericarditis
- Presenting with at least a second recurrence of pericarditis
- Had received nonsteroidal anti-inflammatory drugs (NSAIDs), colchicine, or corticosteroids (alone or in any combination), and doses remained stable or were not increased 3 days prior to first study drug administration
KEY EXCLUSION CRITERIA AT SCREENING1
- Diagnosis of pericarditis secondary to specific prohibited etiologies
- Tuberculosis
- Neoplastic, purulent, or radiation etiologies
- Post-thoracic blunt trauma (eg, motor vehicle accident)
- Myocarditis
- Systemic autoimmune diseases (with exception of Still’s disease)
- Pregnant, breastfeeding, planning a pregnancy, or fathering a child
- History of immunosuppression
- History of chronic or recurrent renal infection or disease
Study population2
- Total population enrolled: 86
- Mean patient age: 45 years (range: 13-78)
- 57% female
- Diagnosis of “idiopathic” pericarditis: 73 (85%)
- Remainder: post cardiac injury pericarditis
- Mean duration of disease: 2.4 years
- Mean pericarditis events per year: 4.4
- Mean qualifying NRS pain score: 6.2
- Mean qualifying CRP level: 6.2 mg/dL
References:
1. Klein AL, Imazio M, Brucato A, et al. RHAPSODY: rationale for and design of a pivotal Phase 3 trial to assess efficacy and safety of rilonacept, an interleukin-1α and interleukin-1β trap, in patients with recurrent pericarditis. Am Heart J. 2020;228:81-90. 2. ARCALYST. Package insert. Kiniksa Pharmaceuticals (UK), Ltd.; 2021.
LASTING PREVENTION
ARCALYST is proven to significantly reduce the risk of pericarditis recurrence.
The primary efficacy endpoint was time to first adjudicated pericarditis recurrence in the randomized withdrawal period.1
ARCALYST
2 of 30 patients treated with ARCALYST had a recurrence during the randomized withdrawal period.1
- The 2 pericarditis recurrences with ARCALYST occurred during temporary interruptions of 1 to 3 weekly doses of ARCALYST.
The median time to recurrence on ARCALYST could not be estimated due to the low number of recurrences.
PLACEBO
23 of 31 patients treated with placebo experienced a recurrence during the randomized withdrawal period.1
The median time to recurrence on placebo was 8.6 weeks (95% CI: 4.0, 11.7).
RAPID RESOLUTION
ARCALYST is shown to provide rapid treatment response.
Secondary endpoints that were assessed during the run-in period.1
RAPID TREATMENT RESPONSE
During the 12-week run-in period, 77 of 79 patients demonstrated a treatment response.*
- Median time to treatment response = 5.0 days (95% CI: 4.0, 7.0)
- Median time to ARCALYST monotherapy = 7.9 weeks
RAPID SYMPTOM RELIEF
During the 12-week run-in period, patients also achieved symptom relief and reduction in inflammation.
- Median time to pain response = 5.0 days
- Median time to CRP normalization = 7.0 days
CRP=C-reactive protein; NRS=Numerical Rating Scale (ranging from 0 to 10 and with higher scores indicating greater pain severity).
*Symptom relief or time to treatment response was defined as the time from the first dose to the first day when pericardial pain was NRS ≤2 and CRP ≤0.5 mg/dL (measured within 7 days before or after the pain response).
FREEDOM FROM STEROIDS AND PAIN
Patients treated with ARCALYST were able to
discontinue corticosteroids.
In the Phase 3 RHAPSODY trial run-in period, patients receiving corticosteroids at baseline were effectively transitioned to ARCALYST.1,3
- Corticosteroids carry the potential risk of side effects that can complicate management4-6
- Use is associated with the risk of recurrence and a prolonged course of disease5,6
- Median time to ARCALYST monotherapy was 7.9 weeks1
44.3% (27 of 61) of patients received corticosteroids at baseline.1
- Each patient treated with corticosteroids at baseline achieved clinical response with ARCALYST monotherapy
- None of the patients treated with corticosteroids at baseline and randomized to ARCALYST experienced a recurrence while on therapy
Patients treated with ARCALYST experienced minimal or no pericarditis pain.1
Secondary efficacy endpoint was assessed during the randomized withdrawal period.1
of days with no pain
or minimal pain (NRS ≤2).1
Compared with 40% for patients on placebo (p<0.0001) at the secondary endpoint assessed at Week 16 of the randomized withdrawal period.
At week 16 of the randomized withdrawal period:
A majority (81%) maintained a clinical response measured at week 16 of the randomized withdrawal period compared with 20% for placebo (p=0.0002).
Patients taking ARCALYST chose to stay on therapy.
in the open-label LTE treatment period.1,3
74 of 75 eligible patients chose to enroll in the ongoing LTE treatment period at the completion of the RW period.