Immune-modulating, clinical-stage product candidates targeting underserved conditions and offering the potential for differentiation.


Program & Target
Phase 1
Phase 2
Phase 3
Commercial Rights



IL-1α & IL-1β


Recurrent Pericarditis
(Excluding MENA)
(Excluding MENA)
(Excluding MENA)
Commercial Rights
Recurrent Pericarditis: Worldwide5 (Excluding MENA)
CAPS: US & Japan
DIRA: US & Japan





Prurigo Nodularis

Vixarelimab Phase 2

Therapeutic Area

Prurigo nodularis (PN) is a chronic inflammatory skin condition characterized by severely pruritic skin nodules. 

Mechanism of Action

Monoclonal antibody inhibiting signaling through oncostatin M receptor beta (OSMRβ).

Vixarelimab inhibits signaling of interleukin-31 (IL-31) and oncostatin M (OSM), two key cytokines implicated in inflammation, pruritus, and fibrosis.

US Prevalence

We estimate that there are approximately 300,000 patients with PN in the United States.


Breakthrough Therapy designation granted by the US Food and Drug Administration (FDA) to vixarelimab for the treatment of pruritus associated with prurigo nodularis.


We are conducting a dose-ranging Phase 2b trial of vixarelimab in patients with prurigo nodularis. Data are expected in the second half of 2022.

  • The Phase 2b trial is a randomized, double-blind, placebo-controlled study designed to investigate the efficacy, safety, and pharmacokinetics of vixarelimab in reducing pruritus in subjects with prurigo nodularis. The trial is expected to enroll approximately 180 patients with moderate-to-severe prurigo nodularis experiencing severe pruritus (WI-NRS ≥ 7 at the screening visit and a mean weekly WI-NRS of ≥ 7 for each of the two consecutive weeks immediately prior to randomization). Patients are required to stop antihistamines and topical treatments, including corticosteroids, for at least two weeks prior to dosing. Prurigo nodularis treatments, other than study drug, are not allowed except for rescue. Patients will be randomized in a 1:1:1:1 fashion to receive vixarelimab 540 mg, 360 mg, 120 mg, or placebo subcutaneously monthly. The primary efficacy endpoint is the percent change from baseline in the weekly-average Worst-Itch Numeric Rating Scale (WI-NRS) at Week 16. Key secondary endpoints include the proportion of patients achieving greater-than-or-equal-to 4-point weekly-average WI-NRS reduction at Week 16 and the proportion of patients achieving a 0/1 score (clear/almost clear) on the prurigo nodularis-investigator’s global assessment (PN-IGA) at Week 16.

In 2020, we reported data from a randomized, double-blind, placebo-controlled Phase 2a clinical trial of vixarelimab in patients with prurigo nodularis.

  • The trial met its primary efficacy endpoint: the reduction in weekly-average WI-NRS from baseline at Week 8 was statistically significantly greater in patients who received vixarelimab versus those who received placebo. Additionally, a statistically significant percentage of vixarelimab recipients achieved a PN-IGA score of 0/1 at Week 8 compared to placebo recipients, and the majority of vixarelimab recipients showed a clinically meaningful greater-than-or-equal-to 4-point weekly-average WI-NRS reduction at Week 8. No dose-limiting adverse experiences were observed. There were no serious adverse events or atopic dermatitis flares.
Unmet Need

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

  • The treatment approach for PN ranges from topical corticosteroids and occlusive corticosteroid-containing bandages for patients who have milder forms of PN to systemic corticosteroids, ultraviolet phototherapy, and systemic therapies such as thalidomide, methotrexate, and cyclosporine for those patients whose conditions don’t improve on initial treatments. Patients have reported using opioid pain medications to attempt to control the disease in its most severe form.
  • Based on market research, we believe ~25% to 30% of subjects are refractory to treatment.





Rheumatoid Arthritis

KPL-404 Phase 1

Mechanism of Action

Monoclonal antibody inhibitor of CD40 signaling. KPL-404 is designed to inhibit CD40-CD40L interaction, a key T-cell costimulatory pathway critical for B-cell maturation and immunoglobulin class switching.


CD40-CD40L interaction is an attractive target for blocking T-cell–mediated B-cell–driven autoimmunity and prevention of solid organ transplant rejection. External proof-of-concept for inhibition of this pathway has been previously established in patients with a broad range of autoimmune diseases, including rheumatoid arthritis, Sjögren’s syndrome, Graves’ disease, systemic lupus erythematosus and solid organ transplant.


We reported final data for our single-ascending-dose Phase 1 study in healthy volunteers for KPL-404, supporting further development in patients. KPL-404 was well tolerated and showed dose-dependent increases in concentration across cohorts. Subjects dosed with KPL-404 10 mg/kg intravenous (IV) showed full receptor occupancy through Day 71 and complete suppression of T-cell Dependent Antibody Response (TDAR) to keyhole limpet hemocyanin (KLH) challenge and rechallenge through at least Day 57. Subjects dosed with KPL-404 5 mg/kg SC showed full receptor occupancy through Day 43 and suppression of TDAR after KLH challenge through at least Day 29. Kiniksa plans to initiate a Phase 2 proof-of-concept trial of KPL-404 in the fourth quarter of 2021.

Rheumatoid arthritis was selected as a well-characterized autoimmune disease with decades of published clinical data across diverse mechanistic classes, allowing for objective evaluation in established endpoints. The pharmacokinetic lead-in of the planned trial supports characterization of chronic administration of KPL-404 in a patient population and provides optionality to evaluate the therapeutic potential of KPL-404 across a range of other autoimmune diseases with pathologies believed to be mediated by the CD40-CD154 pathway.






Evaluating development in rare cardiovascular diseases

1 Approved in the U.S.

2 The FDA granted Orphan Drug exclusivity to ARCALYST in March 2021 for the treatment of recurrent pericarditis and reduction in risk of recurrence in adults and pediatric patients 12 years and older. The European Commission granted Orphan Drug designation to ARCALYST for the treatment of idiopathic pericarditis in 2020.

3 The FDA granted Breakthrough Therapy designation to vixarelimab for pruritus associated with prurigo nodularis in 2020.

4 Phase 2 clinical trials of mavrilimumab in rheumatoid arthritis and giant cell arteritis achieved their primary and secondary endpoints with statistical significance.

5 Kiniksa granted Huadong Medicine exclusive rights in the Asia Pacific Region, excluding Japan.


Patient Support & Treatment Access