Kiniksa Pharmaceuticals : Investor Presentation

Corporate Presentation

JUNE 2024

Forward Looking Statements

This presentation (together with any other statements or information that we may make in connection herewith) contains forward-looking statements with respect to Kiniksa Pharmaceuticals, Ltd. (and its consolidated subsidiaries, collectively, unless context otherwise requires, "Kiniksa," "we," "us" or "our"). In some cases, you can identify forward looking statements by terms such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "goal," "design," "target," "project," "contemplate," "believe," "estimate," "predict," "potential," "strategy," or "continue" or the negative of these terms or other similar expressions, although not all forward-looking statements contain these identifying words. All statements contained in this presentation that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation, statements regarding our strategy; potential value drivers; potential indications; potential market opportunities and competitive position; ongoing, planned and potential clinical trials and other studies; timing and potential impact of clinical data; regulatory and other submissions, applications and approvals; commercial strategy and commercial activities; expected run rate for our cash, cash equivalents and short-term investments; expected funding of our operating plan; financial guidance; and capital allocation. ​

These statements involve known and unknown risks, uncertainties, and other important factors that may cause our actual results, performance or achievements to be materially different from those expressed or implied by the forward-looking statements, including, without limitation: risks arising from the planned redomiciliation of our principal holding company from Bermuda to the United Kingdom; potential delays or difficulties with our clinical trials; potential inability to demonstrate safety or efficacy or otherwise producing negative, inconclusive or uncompetitive results; potential for changes in final data from preliminary or interim data; potential inability to replicate in later clinical trials positive results from earlier trials and studies; our reliance on third parties for manufacturing and conducting clinical trials, research and other studies; risks arising from our technology transfer of ARCALYST drug substance manufacturing; our ability to realize value from our licensing and collaboration arrangements; our ability to source sufficient drug product, as needed, to meet our clinical and commercial requirements; our inability to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities; potential for applicable regulatory authorities to not accept our filings or to delay or deny approval of any of our product candidates or to require additional data or trials to support any such approval or authorization; delays, difficulty or inability to successfully execute on our commercial strategy for ARCALYST; potential changes in our strategy, clinical trial priority, operating plan, business development strategy or funding requirements; raw materials, important ancillary product and drug substance and/or drug product shortages; substantial new or existing competition; risks arising from political and economic instability; and our ability to attract and retain qualified personnel.

​These and the important factors discussed in our filings with the U.S. Securities and Exchange Commission, including underhet caption "Risk Factors" contained therein could cause actual results to differ materially from those indicated by the forward-looking statements made in this presentation. These forward-looking statements reflect various assumptions of Kiniksa's management that may or may not prove to be correct. No forward-looking statement is a guarantee of future results, performance, or achievements, and one should avoid placing undue reliance on such statements. Except as otherwise indicated, this presentation speaks as of the date of this presentation. We undertake no obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.​

​This presentation also contains estimates, projections, and/or other information regarding our industry, our business and the markets for certain of our product candidates, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, clinical trials, studies and similar data prepared by market research firms and other third parties, from industry, medical and general publications, and from government data and similar sources. Information that is based on estimates, forecasts, projections, market research, or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information.

ARCALYST is a registered trademark of Regeneron Pharmaceuticals, Inc. Kiniksa OneConnect is a trademark of Kiniksa Pharmaceuticals. All other trademarks are the property of their respective owners.

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Portfolio of Immune-Modulating Assets

Program

Target

Preclinical

Phase 1

Phase 2

Phase 3

Commercial

CARDIOVASCULAR FRANCHISE

ARCALYST® (rilonacept)1,2,3	Recurrent Pericarditis
IL-1α & IL-1β Trap
Mavrilimumab4	Evaluating Potential Partnership
Anti-GM-CSFRα	Opportunities
AUTOIMMUNE FRANCHISE
Abiprubart	Sjögren's Disease
Anti-CD40	(Expected to initiate in 2H 2024)

Program

Licensee

Exclusive Licensed Territory

OUT-LICENSING AGREEMENTS

ARCALYST (rilonacept)	Huadong Medicine
IL-1α & IL-1β Trap
Mavrilimumab	Huadong Medicine
Anti-GM-CSFRα
Vixarelimab	Roche and Genentech
Anti-OSMRβ

Asia Pacific Region, Excluding Japan

Asia Pacific Region, Excluding Japan

Worldwide

1. Approved in the U.S.; ARCALYST is also approved in the U.S. for cryopyrin-associated periodic syndromes (CAPS) and deficiency of the interleukin-1 receptor antagonist (DIRA); 2) The FDA granted Breakthrough Therapy designation to ARCALYST for recurrent pericarditis in 2019; 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 2021; 3) Kiniksa has worldwide rights, excluding the Middle East and North Africa; Kiniksa granted Huadong Medicine exclusive rights in the Asia Pacific Region, excluding Japan; 4) Phase 2 clinical trials of mavrilimumab in rheumatoid arthritis and giant cell arteritis achieved their primary and secondary endpoints with statistical significance; Kiniksa granted Huadong Medicine exclusive rights in the Asia Pacific Region, excluding Japan

IL-1α = interleukin-1α;IL-1β = interleukin-1β;GM-CSFRα = granulocyte macrophage colony stimulating factor receptor alpha; OSMRβ = oncostatin M receptor beta	3

ARCALYST ®

IL-1α AND IL-1β CYTOKINE TRAP

DISEASE AREA: Recurrent pericarditis1; painful and debilitating auto-inflammatory cardiovascular disease

COMPETITION2: First and only FDA-approved therapy for recurrent pericarditis

REGULATORY: U.S. Orphan Drug exclusivity for treatment of and reduction in risk of recurrence of recurrent pericarditis; European Commission Orphan Drug designation in idiopathic pericarditis

STATUS: FDA-Approved

ECONOMICS: 50/50 split on profit and third-party proceeds

RIGHTS: Kiniksa has worldwide rights3 (excluding MENA) for all indications outside those in oncology and local administration to the eye or ear

1) ARCALYST is also approved and marketed for Cryopyrin-Associated Periodic Syndromes (CAPS) and maintenance of remission of Deficiency of Interleukin-1 Receptor Antagonist (DIRA) in the United States;
2) Drugs@FDA: ARCALYST Prescribing Information, Ilaris Prescribing Information, Kineret Prescribing Information; Kaiser et al. Rheumatol Int (2012) 32:295-299; Theodoropoulou et al. Pediatric Rheumatology 2015, 13(Suppl 1):P155;
Fleischmann et al, 2017 ACR/ARHP Abstract 1196; Kosloski et al, J of Clin Pharm 2016, 56 (12) 1582-1590; Cohen et al. Arthritis Research & Therapy 2011, 13:R125; Cardiel et al. Arthritis Research & Therapy 2010, 12:R192; Hong et al. Lancet	4
Oncol 2014, 15: 656-666; 3) Kiniksa granted Huadong Medicine exclusive rights in the Asia Pacific Region, excluding Japan;
IL-1α = interleukin-1α ; IL-1β = interleukin-1β; MENA = Middle East North Africa

Pericarditis Epidemiology

Of the 14,000 target population with multiple recurrences, there is a high turnover of ~50% of patients each year, meaning ongoing opportunities to ensure diagnosis and targeted treatment

	Recurrent	Pericarditis
	Pericarditis	~160,000
Multiple	Recurrent	Pericarditis
~40,000
Recurrences	Pericarditis	~160,000
~14,000	~40,000

Approximately 14,000 recurrent pericarditis patients in the U.S. suffer from persistent underlying disease, with multiple recurrences and inadequate response to conventional therapy1

~160,000: Epidemiological analysis using large national surveillance databases to calculate the pooled annualized prevalence of pericarditis

(Basis for Orphan Drug Designation)2

~40,000: Up to 30% experience at least one recurrence; some recur over multiple years3,4

~14,000: Nearly 50% annual turnover with ~7,000 patients entering into the pool each year5

All figures annual period prevalence

1. Cremer et al. American Journal of Cardiology. 2016;2311-2328; 2) DOF, Kiniksa Pharmaceuticals, Ltd.; 3) Imazio et al. Circulation. 2005;112:2012-2016; 4) Adler et al. Circulation. 1998;97:2183-2185; 5) Klein A, Cremer P, Kontzias A, et al. US database study of clinical burden and unmet need in recurrent pericarditis. J Am Heart Assoc. 2021; 10:e018950. doi:10.1161/JAHA. 120.018950

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Role of IL-1α and IL-1β in the Autoinflammatory Cycle of Recurrent Pericarditis

In addition to inflammatory cytokines such as IL-6, promotion and progression of the inflammatory process in pericarditis is due to IL-1α and IL-1β

CRP, C-reactive protein; DAMPs, damage- associated molecular patterns; IL, interleukin; PAMPs, pathogen-associated molecular patterns; WBC, white blood cell.

The Autoinflammatory Cycle of Recurrent Pericarditis:

Tissue damage caused by IL-1α and IL-1β in the pericardium stimulates additional IL-1α and IL-1β, thereby creating a cycle of perpetual pericardial inflammation

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RESONANCE: Growing Adoption of ARCALYST as a Steroid-Sparing Therapy1,2

RESONANCE is an ongoing observational registry in up to 500 patients from 29 US sites, collecting real-world data on RP natural history and disease management over a 6-yearintensive-observation period

The proportion (n=264) of IL-1 pathway inhibition use increased from 11% of patient-years before ARCALYST availability to 25% of patient- years in 2023, with ARCALYST use driving this observed shift

No RP-specific treatment		csDMARDs+		Aspirin/NSAIDs/colchicine		Corticosteroids¥		IL-1 pathway inhibition€

A = anakinra; R = rilonacept; *Partial year prior to rilonacept availability; **Partial year after rilonacept availability April 1, 2021 - Dec 31, 2021

• Not mutually exclusive, pts could contribute whole/fractions of PY to multiple medication classes (i.e., includes combination therapy & sequential therapy) € 24% of pts using anakinra went on to use rilonacept; of those, 9% used anakinra for ≤30 days (possibly as short-term bridge therapy)
  ¥ 16% of pts who utilized steroids did so as short-term bridge therapy (≤30 days) before transitioning to rilonacept + Includes azathioprine, methotrexate, hydroxychloroquine/Plaquenil®, sulfasalazine
  £ Data censored at last check-in visit

Total absolute pt counts: rilonacept (n=89); anakinra (n=45), corticosteroids (n=85), aspirin/NSAIDs/colchicine (n=239), csDMARDs (n=12)

csDMARDs: conventional disease-modifying antirheumatic drugs

In a sub-analysis of patients failing Aspirin/NSAIDs/Colchicine

(n=101), substantially more patients transitioned to ARCALYST, and

fewer patients transitioned to steroids over time

csDMARDs

Corticosteroids

Anakinra¥

Rilonacept€

*Partial year 2021 prior to rilonacept availability on April 1, 2021; **Partial year 2021 after rilonacept availability after April 1, 2021

• € Of 41 pts starting rilonacept after aspirin/NSAIDs/colchicine, 4 pts utilized steroids as a short-term bridge prior to starting rilonacept (1 pt in 2021, 2 pts in 2022, 1 pt in 2023); 1 pt (in 2022) utilized anakinra as a short-term bridge prior to starting rilonacept

• Of 16 pts starting anakinra after aspirin/NSAIDs/colchicine, 3 pts utilized steroids as a short-term bridge prior to starting anakinra (1 pt in 2021, 2 pts in 2022)
  £ Data censored at last check-in visit
  csDMARDs: conventional disease-modifying antirheumatic drugs

This interval analysis included medication class use data from study start (March 2021) until data cutoff (Feb 15, 2024) collected from 21 US sites

1. Luis, S, Cremer, P, Raisinghani, A. et al. Rilonacept utilization in a steroid-sparing paradigm for recurrent pericarditis: real world evidence demonstrating increased adoption.	7
J Am Coll Cardiol. 2024 Apr, 83 (13_Supplement) 408; 2. Clinicaltrials.gov NCT04687358

Commercial Experience Highlights Successful Targeting Strategy with Further Upside Potential

Recurrent Pericarditis Annual Epidemiology: ~40,000

1ST RECURRENCE
~26,000	LOWEST
	SHARE
ARCALYST
LABEL
2ND RECURRENCE	MODERATE SHARE
~7,000
14,000
TARGET
POPULATION
3RD RECURRENCE	HIGH SHARE
~3,500
≥4TH
RECURRENCE	HIGH SHARE
~3,500
	ARCALYST Usage Since Launch

SIGNIFICANT MARKET POTENTIAL

~9% penetration into the 14K target population at the end of Q4 2023

ARCALYST PATIENTS BY

FLARE STATUS AT INITIATION1

NOTIN ACTIVE FLARE

~20%

INACTIVE FLARE

~80%

Commercial nationwide experience demonstrates the vast majority of patients are within the target population of 14K multiple-recurrent patients, while the broad label allows for additional upside

Klein A, Cremer P, Kontzias A, Furqan M, Tubman R, Roy M, Magestro M. Annals of Epidemiology. 2019;36:71; Lin D, Majeski C, DerSarkissian M, Magestro M, Cavanaugh C, Laliberte F, Lejune D, Mahendran M, Duh M, Klein A, Cremer P,
Kontzias A, Furqan M, Tubman R, Roy M, Mage. (Nov, 2019). Real-World Clinical Characteristics and Recurrence Burden of Patients Diagnosed with Recurrent Pericarditis in the United States. Poster session presented at the American Heart	8
Association, Philadelphia, PA.

1) Kiniksa Pharmaceuticals data on file 2024. 2) Other late line agents include anakinra, azathioprine, methotrexate

Strong ARCALYST Growth Driven by Robust Commercial Execution

Significant Net Revenue Growth

Key Revenue Drivers1

85% Year-over-Year

Growth

	$78.9M
$42.7M
Q1 2023	Q1 2024

11% Quarter-over Quarter

Growth

	$78.9M
$71.2M
Q4 2023	Q1 2024

Total Prescribers	~2,000
(Since Launch)
Repeat Prescribers	~24%
(% of Total)
Payer Approval	>90%
(% of Completed Cases)
Average Total	~23 months
Duration
of Therapy
Patient Compliance	>85%

1) Data since launch through 3/31/2024	9

Key Executional Priorities to Drive Greater Patient and Physician Adoption

Identify appropriate patients and drive a proactive mindset with physicians and patients

Close the ARCALYST knowledge gap with physicians

Externally: U.S. thought leaders have introduced treatment paradigms for recurrent pericarditis that recommend IL-1antagonists, such as ARCALYST, be used ahead of corticosteroids1

Our Aim: Continue to drive the evolution of this treatment paradigm

Intended Future Use Among Target Healthcare Providers2

Advance the treatment paradigm

ARCALYST

Corticosteroids

17%

42%

83%

58%

Decrease

Stay the Same

Increase

Educate on duration of disease and treatment

0%

20%

40%

60%

80%

100%

• Target physicians who have knowledge of ARCALYST overwhelmingly expect to increase their prescribing of ARCALYST in next 6 months
• The biggest barriers for physicians to prescribing ARCALYST are limited knowledge about the product and/or perception of the payer approval process

1. Dong, Klein, Wang. Paradigm Shift in Diagnosis and Targeted Therapy in Recurrent Pericarditis. Springer Nature. 2023.; Klein, Cremer, Kafil. Recurrent Pericarditis A Promising Future for IL-1 Blockers in Autoinflammatory Phenotypes. Journal of the American College of Cardiology, Editorial Comment. 2023.; Thomas, Bonaventura, Vecchié, et al. Interleukin-1 blockers for the treatment of recurrent pericarditis: pathophysiology, patient reported outcomes and perspectives. Journal of Cardiovascular Pharmacology. 2023.; Imazio, Mardigyan, Andreis, et al. New developments in the management of recurrent pericarditis. Canadian

Journal of Cardiology. 2023.; Kumar, Khubber, Reyaldeen, et al. Advances in Imaging and Targeted Therapies for Recurrent Pericarditis. JAMA Cardiology Review. 2022.; Sushil, Cremer, Raisinghani.	10
2) HCP Market Research, Q3 2023; Kiniksa Data on File.