Is there literature comparing rilonacept to anakinra in the management of pericarditis?

Comment by InpharmD Researcher

There is currently no head-to-head randomized controlled trial comparing rilonacept and anakinra in the management of pericarditis. However, both agents have independently demonstrated significant efficacy in reducing recurrence rates in patients with corticosteroids-dependent or colchicine-resistant disease, supporting the role of IL-1 inhibition as a key therapeutic strategy. Rilonacept, as shown in the RHAPSODY trial, produced a marked reduction in recurrence risk (7% vs. 74% with placebo; HR 0.04), rapid symptom relief, and normalization of inflammatory markers. Similarly, anakinra in the AIRTRIP trial has shown to reduce recurrence risk over a median follow-up of 14 months and serve as an effective steroid-sparing option. Overall, both therapies are effective and well-tolerated, with mild adverse events and favorable safety profiles. Future head-to-head trials are warranted to compare efficacy and safety between rilonacept vs. anakinra in the management of pericarditis.

Rilanocept anakinra pericarditis

Background

The 2022 European Heart Journal review offers a comprehensive overview of the application of anti-interleukin-1 (IL-1) agents in the management of recurrent pericarditis. The review discusses three primary anti-IL-1 agents—anakinra, rilonacept, and canakinumab—emphasizing their mechanisms and therapeutic roles. Anakinra, a recombinant human IL-1 receptor antagonist, and rilonacept, a fusion protein that acts as a soluble decoy receptor for IL-1a and IL-1b, have demonstrated significant efficacy and safety in patients who are corticosteroid-dependent and colchicine-resistant. Through randomized controlled trials and observational studies, these agents have significantly reduced the incidence of pericarditis recurrences, with minimal severe side effects and common adverse events like injection site reactions being well-tolerated by patients. The paper outlines the historical progression and clinical trials that have validated the use of anti-IL-1 agents, particularly focusing on anakinra and rilonacept. The authors detail findings from various studies, including the AIRTRIP and RHAPSODY trials, which demonstrated that both agents substantially lowered the recurrence rates of pericarditis when compared to placebo treatments. The methodological rigor of these trials, employing randomized, double-blind designs with extensive follow-up durations, provides robust support for the role of IL-1 inhibition in the therapeutic paradigm of recurrent pericarditis. The synthesis of these trials' outcomes, along with safety profiles characterized by low rates of serious adverse events, establishes anti-IL-1 agents as key advancements in managing this chronic and often refractory condition. Similarly, a 2022 systematic review and meta-analysis meticulously examined the therapeutic efficacy of rilonacept and anakinra in managing recurrent pericarditis, particularly in cases unresponsive to conventional therapies. The results from the systematic review highlighted the substantial benefits of anti-IL-1 therapy, with both rilonacept and anakinra significantly reducing the recurrence of pericarditis. The Phase III trial of rilonacept included in the analysis underscored its capacity to rapidly resolve acute episodes while decreasing the risk of recurrence, with marked improvements noted in quality of life and management of symptoms such as pain and inflammation. Similarly, evidence from studies on anakinra indicated its effectiveness as an alternative treatment for corticosteroid-dependent, recurrent pericarditis. The statistical analysis emphasized the superior odds ratios for therapeutic success with these agents, substantiating their role as viable options in refractory cases. Despite some limitations, including a relatively small number of RCTs, the review provides a compelling argument for incorporating anti-IL-1 therapies into the clinical management of recurrent pericarditis, emphasizing the need for further research in larger, diverse populations. [1], [2]

A 2021 review highlighted recent studies on the use of anti-IL-1 drugs, such as anakinra and rilonacept, in recurrent pericarditis. The RHAPSODY study, included in the review, focused on rilonacept, showing promising phase 3 results in terms of efficacy and safety. The increasing evidence supports the use of anti-IL-1 agents in patients with recurrent pericarditis and a significant inflammatory phenotype, indicating a shift towards more tailored therapeutic approaches in managing this condition. According to the 2021 review, the pathogenesis of recurrent pericarditis is linked to both adaptive and innate immune reactions, potentially triggered by infectious or environmental factors in genetically susceptible individuals. The study highlighted that in autoimmune pericarditis, viral infections can initiate autoimmune responses through molecular mimicry. Similarly, autoinflammatory pericarditis involves the innate immune system, with diseases like familial Mediterranean fever (FMF) and tumor necrosis factor receptor-associated periodic syndrome (TRAPS) shedding light on the role of inflammasome activation and IL-1 overproduction. These insights underline the potential of targeting IL-1 with specific inhibitors as a promising treatment avenue, offering relief for patients suffering from recurrent pericarditis when traditional therapies prove inadequate. [3]

A 2024 review delves into the clinical utility of rilonacept for the treatment of recurrent pericarditis (RP), emphasizing its design, development, and therapeutic role. The review outlines the significant challenges faced in managing RP due to its unpredictable relapses and the limited efficacy of traditional treatments like NSAIDs, glucocorticoids, and colchicine. The paper highlights that a breakthrough in this therapeutic area was achieved by targeting the inflammatory pathways, specifically the IL-1 cytokine, given its crucial role in the pathophysiology of pericarditis. The advent of IL-1 inhibitors, particularly rilonacept, marks a paradigm shift in treating RP resistant to conventional therapies. Rilonacept is described as a dimeric fusion protein that acts as a soluble decoy receptor, binding to IL-1α and IL-1β, thus inhibiting their inflammatory cascade. Its pharmacokinetic profile allows for weekly dosing, enhancing patient adherence. The publication emphasizes that clinical trials such as RHAPSODY have provided robust evidence of rilonacept’s efficacy in reducing pericarditis recurrence. In this pivotal phase 3 trial, patients with recurrent pericarditis showed remarkable improvement in both the frequency and severity of recurrences, with a significant reduction in inflammatory markers like C-reactive protein (CRP). Rilonacept was shown to not only alleviate symptoms but also enable the safe withdrawal or tapering of other medications, like glucocorticoids, thereby reducing their associated side effects. The RHAPSODY trial reported a noteworthy risk reduction of recurrence, with the median time to first recurrence significantly extended in the rilonacept group compared to placebo. Adverse events were mostly mild, including injection site reactions and upper respiratory tract infections, underscoring the favorable safety profile of rilonacept. These findings collectively underline rilonacept as a promising treatment option for RP, offering an improved quality of life and a reduced healthcare burden associated with this challenging condition. [4]

A 2021 phase 3, double-blinded, placebo-controlled, multicenter randomized-withdrawal trial investigated the efficacy and safety of rilonacept in patients experiencing symptomatic recurrent pericarditis with elevated CRP levels despite conventional therapy. This trial enrolled a total of 86 patients, with 61 completing the run-in period and undergoing randomization. Participants received an initial subcutaneous dose of rilonacept 320 mg, followed by 160 mg weekly for 12 weeks. Responders were then randomized to continue rilonacept 160 mg weekly or switch to placebo. The primary endpoint focused on the recurrence of pericarditis, while secondary endpoints assessed clinical response, CRP normalization, and discontinuation of standard therapy in favor of rilonacept monotherapy. The study, with a mean participant age of 44.7 years and a predominantly idiopathic cause of pericarditis (85%), demonstrated a substantial reduction in recurrence rates of pericarditis in those receiving rilonacept compared to placebo (7% vs. 74%), with a hazard ratio of 0.04 (95% CI, 0.01 to 0.18; P<0.001). Rilonacept led to rapid resolution of acute symptoms, significantly reduced pain within a median of 5 days, and normalized CRP levels in 7 days. The median duration of treatment, including the run-in period, was 9 months. All patients initially on corticosteroids were tapered off effectively to rilonacept monotherapy within 8 weeks. Although four participants discontinued due to adverse events, the therapy was generally well-tolerated; injection-site reactions and upper respiratory tract infections were the most common side effects. These findings underscore rilonacept's potential as a safe, effective, and steroid-sparing option for patients suffering from recurrent pericarditis, marking a significant advancement in targeted therapy for this inflammatory condition. [5]

References: [1] Imazio M, Lazaros G, Gattorno M, et al. Anti-interleukin-1 agents for pericarditis: a primer for cardiologists. Eur Heart J. 2022;43(31):2946-2957. doi:10.1093/eurheartj/ehab452
[2] Affas ZR, Rasool BQ Sr, Sebastian SA, et al. Rilonacept and Anakinra in Recurrent Pericarditis: A Systematic Review and Meta-Analysis. Cureus. 2022;14(11):e31226. Published 2022 Nov 8. doi:10.7759/cureus.31226
[3] Bizzi E, Trotta L, Pancrazi M, et al. Autoimmune and Autoinflammatory Pericarditis: Definitions and New Treatments. Curr Cardiol Rep. 2021;23(9):128. Published 2021 Jul 28. doi:10.1007/s11886-021-01549-5
[4] Vlachakis PK, Theofilis P, Soulaidopoulos S, Lazarou E, Tsioufis K, Lazaros G. Clinical Utility of Rilonacept for the Treatment of Recurrent Pericarditis: Design, Development, and Place in Therapy. Drug Des Devel Ther. 2024;18:3939-3950. Published 2024 Sep 4. doi:10.2147/DDDT.S261119
[5] Anthony CM, Chetrit M, Klein AL. IL-1 trap rilonacept for recurrent pericarditis: RHAPSODY study. American College of Cardiology. Published February 24, 2021.
Literature Review

A search of the published medical literature revealed 3 studies investigating the researchable question:

Is there literature comparing rilonacept to anakinra in the management of pericarditis?

Level of evidence

C - Multiple studies with limitations or conflicting results  Read more→



Please see Tables 1-3 for your response.


 

Table 1: Studies evaluating IL-1 antagonists
Study, Journal Author Year Study Design Sample Size Treatment vs. Control Group Dose; Duration Primary Endpoint Results
IRAP Study, European Journal of Preventative Cardiology Imazio et al 2019 Single arm, multi-centre observational study 224 All patients received Anakinra for 6 months Anakinra 100mg daily for 6 months 1) Recurrence of pericarditis

2) Hospitalization + Emergency Department presentations

3) Corticosteroid dependence
1) Recurrence of pericarditis reduced from 2.33 to 0.39 flares per patient per year p < 0.001.
One recurrence every 939 days with therapy, reduced from one every 157 days at baseline, a reduction of 83%
p < 0.001

2) Admissions were reduced from 1.08 to 0.10 /patient/year; Hospitalizations reduced from 0.99 to 0.13 /patient/year
p < 0.001

3) Corticosteroid dependence was reduced with 180 (80%) still dependent at enrolment reduced to 61
p<0.001
AIRTRIP, Journal of the American Medical Association (JAMA) Brucato et al 2016 Randomized Double-Blind placebo- controlled 21 All patients received Anakinra for 60 days and were randomized 1:1 to continue Anakinra or placebo Anakinra 100mg daily;
6 months
1) Recurrence of pericarditis at 8 months Anakinra = 2 (18%)
Placebo = 9 (90%)
American Journal of Cardiology Jain et al 2015 Case series 13 All patients received Anakinra Anakinra 100mg daily; 24 months (7 patients)
Anakinra 100mg daily; 8-11 months (4 patients)
Anakinra 100g then tapered to 50mg daily;  (4 patients)
1) Symptom relief

2) Time to initial response
Complete symptom relief = 12 (92%)

Partial symptoms relief = 1 (8%)

Time to initial response = 2-5 days
American Heart Journal Klein et al 2020 Phase 2 Prospective Study 25  --  -- 1) Pericarditis pain using an 11-point pain numeric rating scale (NRS)

2) CRP change
Reduction in pericarditis frequency with a decreased annualized incidence of 3.9 (SD 3.66) episodes per year for all patients prior to study entry to 0.18 (SD 0.62)
References:
[1] [1] Anthony CM, Chetrit M, Klein AL. IL-1 trap rilonacept for recurrent pericarditis: RHAPSODY study. American College of Cardiology. Published February 24, 2021.
Effect of Anakinra on Recurrent Pericarditis Among Patients With Colchicine Resistance and Corticosteroid Dependence
Design

Double-blind, placebo-controlled, randomized withdrawal trial

N= 21

Objective To determine the efficacy of anakinra for colchicine-resistant and corticosteroid-dependent recurrent pericarditis
Study Groups

Anakinra (n= 11)

Placebo (n= 10)

Inclusion Criteria Patients with recurrent pericarditis (≥3 previous recurrences), elevation of C-reactive protein, colchicine resistance, and corticosteroid dependence
Exclusion Criteria Pregnant or lactating; history of immunodepression; positive HIV test; positive QuantiFERON or purified protein derivative test; recent live vaccinations; history of malignancy within the past 5 years; significant other medical conditions; history of recurrent or active infections
Methods

In a study evaluating the efficacy of anakinra for treating pericarditis, 21 patients were randomized into two groups at day 60, marking the start of a double-blind withdrawal phase. Eleven patients continued receiving anakinra as originally assigned, while the remaining ten switched to placebo, maintaining the blinding for both patients and physicians. The study focused on open-label anakinra administration (100 mg/day for adults and 2 mg/kg/day up to 100 mg for children) initially, with clinical, laboratory, electrocardiographic, and echocardiographic assessments conducted on days 1, 4, and 8. Patients demonstrating at least a 30% reduction in pericardial pain (measured by a 21-circle visual analog scale), a 30% or greater decrease in C-reactive protein (CRP) concentration, and no increase in pericardial effusion on echocardiogram continued in the study. Those who did not meet these criteria were labeled as "early treatment failures" and became eligible for rescue therapy and study withdrawal. Responder status was reassessed on day 8, leading to the withdrawal of NSAIDs and corticosteroids for responders, with anakinra treatment persisting until day 60. A total of 21 patients then entered the randomized, double-blind phase—receiving either continued anakinra or placebo for an additional six months, with placebo appearing identical to anakinra to maintain blinding. The dosing and administration were carefully managed through a computer-based automated sequence to ensure a 1:1 randomization ratio. Patients were allowed to continue their current medications for pericarditis at study entry, except for other IL-1 blockers. All participants were on long-term corticosteroid therapy without any dose increase in the three days prior to enrollment, and most were using colchicine, with two patients having withdrawn due to poor tolerability and one for lack of efficacy. Co-medications were unchanged until day 8 for responders, after which NSAIDs were tapered and withdrawn within 15 days, and corticosteroid therapy was reduced over six weeks (5 mg per week for adults and 0.2 mg/kg per week for children). Colchicine discontinuation was optional. 

Duration June 2014 to October 2015
Outcome Measures

Primary: Recurrent pericarditis and time to recurrence after randomization

Secondary: Responder status, time to response in open-label phase, percentage of patients with corticosteroid withdrawal at 6 weeks

Baseline Characteristics   Anakinra (n= 11) Placebo (n= 10)
Age, mean (SD) 46.5 ± 16.3 44 ± 12.5
Female, No. (%) 7 (63.6%) 7 (70.0%)
Pain VAS score, mean (SD) 7.1 ± 1.8 8.3 ± 1.3
CRP level, mean (SD), mg/dL 3.7 ± 2.2 4.8 ± 5.3
Pericardial effusion, No. (%) 9 (81.8%) 9 (90.0%)
Previous recurrences of pericarditis, mean (SD) 6.9 ± 2.9 6.7 ± 4.3
Results   Placebo (n= 10) Anakinra (n= 11) p-value
Risk of recurrence, No. (%) 9 (90%) 2 (18%) 0.001
Incidence rate, % patients/y 2.06 0.11  --
Incidence rate ratio (95% CI)  0.055 (0.006-0.264) <0.001
Flare-free survival, median (IQR), d 72 (64-150) Not calculable <0.001
Days to flare, mean (range) 28.4 (2-90) 76.5 (33-120) <0.001
Adverse Events Overall adverse events: 95.2% in anakinra group; local skin reactions (95.2%); herpes zoster (4.8%); transaminase elevation (14.3%); ischemic optic neuropathy (4.8%). No adverse events in placebo group.
Study Author Conclusions In patients with recurrent pericarditis with colchicine resistance and corticosteroid dependence, anakinra compared with placebo reduced the risk of recurrence over a median of 14 months. Larger studies are needed to replicate these findings as well as to assess safety and longer-term efficacy.
Critique The study demonstrated a significant reduction in recurrence of pericarditis with anakinra, but the small sample size and short follow-up period limit the generalizability of the findings. The study was not powered to assess long-term safety or adverse events comprehensively. Larger, longer-term studies are needed to confirm these results.
References:
[1] [1] Brucato A, Imazio M, Gattorno M, et al. Effect of Anakinra on Recurrent Pericarditis Among Patients With Colchicine Resistance and Corticosteroid Dependence: The AIRTRIP Randomized Clinical Trial. JAMA. 2016;316(18):1906-1912. doi:10.1001/jama.2016.15826
Phase 3 Trial of Interleukin-1 Trap Rilonacept in Recurrent Pericarditis
Design

Phase 3 multicenter, double-blind, event-driven, randomized-withdrawal trial

N= 86

Objective To test the primary hypothesis that rilonacept would lead to a lower risk of pericarditis recurrence than placebo
Study Groups

Rilonacept (n= 30)

Placebo (n= 31)

Inclusion Criteria Adult and adolescent patients (≥12 years of age) with recurrent pericarditis, presenting with acute signs and symptoms of pericarditis during at least a second recurrence, despite treatment with NSAIDs, colchicine, or oral glucocorticoids. A pain score of at least 4 on a numerical rating scale and a CRP level of at least 1 mg per deciliter within 7 days before the first administration of trial treatment
Exclusion Criteria Not explicitly stated in the provided text
Methods

Eligible patients required a minimum pain score of 4 on a numerical rating scale and a CRP level of at least 1 mg/dL prior to their first dose of rilonacept. Following a screening phase, a 12-week run-in period commenced where all patients received subcutaneously administered rilonacept, starting with a loading dose of 320 mg (or 4.4 mg/kg for patients under 18), followed by weekly maintenance doses of 160 mg (or 2.2 mg/kg for younger patients). This period allowed for weaning from background therapies and included a phase of rilonacept monotherapy. Patients showing clinical response (CRP ≤0.5 mg/dL and minimal pain) were randomized to continue rilonacept or switch to placebo in a withdrawal phase. The trial concluded upon recording 22 verified post-randomization recurrences, defined by renewed pericarditis pain and elevated CRP along with objective evidence. This marked a transition to a long-term extension offering up to 24 months of open-label rilonacept. Efficacy assessments focused on recurrence rates, consistent clinical response at 16 weeks, and days with minimal or no pain, supplemented by the patient's global impression of severity. Secondary endpoints during the run-in period included time to pain response, CRP normalization, treatment response, and discontinuation of standard therapy in favor of rilonacept monotherapy. Analyses of recurrence events were blind to trial-group assignments, ensuring the integrity of the findings.

Duration Enrollment: January 9, 2019, to January 17, 2020 Run-in period: 12 weeks Randomized-withdrawal period: Until May 29, 2020
Outcome Measures

Primary: Time to the first pericarditis recurrence

Secondary: Percentage of patients with persistent clinical response at week 16, percentage of days with no or minimal pain through week 16, percentage of patients with absent or minimal pericarditis symptoms at week 16

Baseline Characteristics   Run-In Period Randomized-Withdrawal Period - Rilonacept (N=30) Randomized-Withdrawal Period - Placebo (N=31)
Age, Mean — yr 44.7 ± 16.1 48.0 ± 15.7 44.8 ± 14.5
Female sex — no. (%) 49 (57%) 16 (53%) 16 (52%)
Cause of pericarditis — no. (%) - Idiopathic 73 (85%) 26 (87%) 26 (84%)
Medication used in the qualifying episode of pericarditis — no. (%) - NSAID 58 (67%) 20 (67%) 19 (61%)
Medication used in the qualifying episode of pericarditis — no. (%) - Colchicine 69 (80%) 27 (90%) 26 (84%)
Medication used in the qualifying episode of pericarditis — no. (%) - Glucocorticoid 42 (49%) 14 (47%) 14 (45%)
Pain score for the qualifying episode, according to the numerical rating scale 6.2 ± 1.8 6.4 ± 1.7 6.3 ± 1.9
C-reactive protein level for the qualifying episode — mg/dl 6.2 ± 6.7 6.6 ± 7.3 6.0 ± 5.1
Results   Rilonacept (N=30) Placebo (N=31) Hazard Ratio or Difference (95% CI) P Value
Median time to pericarditis recurrence (95% CI) — wk NE* 8.6 (4.0–11.7) 0.04 (0.01–0.18) <0.001
Persistent clinical response 81 (58–95) 20 (6–44) 61 (37–85) <0.001
Days with no or minimal pain 97.7 ± 7.5 45.9 ± 7.2 51.8 (35.3–68.4) <0.001
Absent or minimal pericarditis symptoms 81 (58–95) 25 (9–49) 56 (31–81) <0.001
Abbreviations: NE*: Not estimated
Adverse Events Injection-site reactions and upper respiratory tract infections were the most common adverse events. Injection-site reactions occurred in 29 patients (34%), all of whom were rilonacept recipients. Upper respiratory tract infection was reported in 7 patients (23%) who received rilonacept before bailout and in no patients who received placebo before bailout. All the upper respiratory tract infections were mild or moderate in severity.
Study Author Conclusions Among patients with recurrent pericarditis, rilonacept led to rapid resolution of recurrent pericarditis episodes and to a significantly lower risk of pericarditis recurrence than placebo.
Critique The study demonstrated a significant reduction in pericarditis recurrence with rilonacept compared to placebo, with rapid resolution of symptoms. However, the relatively small sample size and the randomized-withdrawal design limit the generalizability of the findings. The trial's focus on patients who had already responded to therapy may not reflect outcomes in a broader population. Additionally, the long-term effects and safety of rilonacept require further investigation.
References:
[1] [1] Klein AL, Imazio M, Cremer P, et al. Phase 3 Trial of Interleukin-1 Trap Rilonacept in Recurrent Pericarditis. N Engl J Med. 2021;384(1):31-41. doi:10.1056/NEJMoa2027892