Familial Cold Autoinflammatory Syndrome 2

Phase 2 trials of VTX958 (TYK2 inhibitor) are ongoing in plaque psoriasis, Crohn’s disease and psoriatic arthritis, with topline Phase 2 data in plaque psoriasis expected in Q4 2023 The Phase 2 trial of VTX002 (S1P1R modulator) in ulcerative colitis (UC) is on track to complete enrollment by mid-2023, with topline data expected in H2 2023 Initiated a Phase 2 proof-of-mechanism trial of VTX2735 (peripheral NLRP3 inhibitor) in patients with cryopyrin-associated periodic syndrome (CAPS) Cash, cash equivalents and marketable securities of $356.6 million at the end of 2022 plus an additional $48.4 million in net proceeds raised in Q1 2023 under our “At-the-market” (ATM) program are expected to fund operations into 2025 Ventyx to host conference call and webcast today at 4:30PM ET ENCINITAS, Calif., March 23, 2023 (GLOBE NEWSWIRE) -- Ventyx Biosciences, Inc. (Nasdaq: VTYX) (“Ventyx”), a clinical-stage biopharmaceutical company focused on advancing novel oral therapies that address a broad range of inflammatory diseases with significant unmet medical need, today announced financial results for the fourth quarter and full year ended December 31, 2022, and highlighted recent pipeline and business progress. “I am proud of our team’s exceptional performance in 2022 as we continued to build an amazing team, strengthen our financial position and successfully advance our portfolio of wholly-owned, internally-discovered small molecules targeting large immunology markets with high unmet medical need,” said Raju Mohan, Chief Executive Officer. “We look forward to a potentially breakthrough year in 2023, with multiple key clinical milestones, including topline Phase 2 data for VTX002 in ulcerative colitis expected in H2 2023 and topline Phase 2 data for VTX958 in plaque psoriasis expected in Q4 2023. Additionally, we recently initiated a Phase 2 proof-of-mechanism trial of VTX2735 in CAPS patients, and we look forward to initiating a Phase 1 trial of our novel CNS-penetrant NRLP3 inhibitor VTX3232 in the first half of 2023.” Pipeline Updates VTX958 (TYK2 Inhibitor): Enrollment is ongoing in the Phase 2 SERENITY trial of VTX958 in moderate to severe plaque psoriasis, the Phase 2 HARMONY trial in moderately to severely active Crohn’s disease and the Phase 2 TRANQUILITY trial in active psoriatic arthritis. Topline data from the Phase 2 SERENITY psoriasis trial are anticipated in Q4 2023. Topline readouts from the Phase 2 HARMONY and Phase 2 TRANQUILITY trials are expected in 2024. Additionally, we are developing an extended release (ER) tablet formulation for VTX958 in collaboration with leading formulation development partners. We expect to provide an update on VTX958 ER tablet development in mid-2023 following completion of initial in-human testing. We have also begun a wide range of other Phase 3 enabling activities. VTX002 (S1P1R Modulator): We continue to make significant progress enrolling the Phase 2 trial of VTX002 in moderately to severely active ulcerative colitis. We expect to complete enrollment by mid-2023 and topline results are anticipated in the second half of 2023. At our investor R&D Day in January, we announced preliminary pharmacodynamic (PD) data from the open-label extension of the ongoing Phase 2 trial. Among patients completing Week 26 (13 weeks of blinded therapy followed by 13 weeks of open-label treatment with VTX002 60mg) as of January 15, 2023, a mean reduction from baseline in absolute lymphocyte count of 74% was observed. We believe these preliminary data suggest VTX002 may achieve a greater pharmacodynamic response compared to other S1P receptor modulators approved or in development for the treatment of ulcerative colitis, which may translate to an improved efficacy pro UC. VTX2735 (Peripheral NLRP3 Inhibitor): We have initiated a Phase 2 proof-of-mechanism trial of VTX2735 in patients with familial cold autoinflammatory syndrome (FCAS). FCAS is the most common subset of cryopyrin-associated periodic syndrome (CAPS), a group of rare autoinflammatory conditions caused by gain-of-function mutations in the NLRP3 gene. In addition to CAPS, we believe systemic NLRP3 inhibition with VTX2735 may have therapeutic potential across a broad range of chronic inflammatory conditions that are characterized by NLRP3-induced excess IL-1β, including dermatologic, rheumatologic and cardiovascular diseases. VTX3232 (CNS-penetrant NLRP3 Inhibitor): We expect to initiate a Phase 1 trial of VTX3232 during the first half of 2023. The Phase 1 trial is expected to characterize the safety, target engagement and bioavailability of VTX3232 in the central nervous system of healthy volunteers. We believe that the pro VTX3232 may define it as a class-leading therapeutic for a range of neuroinflammatory conditions with high unmet medical need, including Parkinson’s disease, Alzheimer’s disease and amyotrophic lateral sclerosis, among others. Discovery Programs: We continue our lead optimization efforts on the recently disclosed program focused on small molecule antagonists of IL-4Rα, a target validated by biologics in multiple large autoimmune indications, including atopic dermatitis, asthma and eosinophilic esophagitis. We are advancing multiple internally discovered novel chemical series through lead optimization with the goal of establishing in vivo proof-of-concept and nominating a lead candidate in 2023. Fourth Quarter and Full Year 2022 Financial Results: The amounts presented below for the fourth quarter and full year ended December 31, 2022 reflect the financial results of Ventyx Biosciences, Inc. and its two wholly-owned subsidiaries, Oppilan Pharma Limited (Oppilan) and Zomagen Biosciences Ltd. (Zomagen), on a consolidated basis. The amounts presented below in the Consolidated Statements of Operations and Comprehensive Loss for the year ended December 31, 2021 reflect the financial results of Ventyx, as well as the financial results of Oppilan and Zomagen from the date of acquisition (February 26, 2021), on a consolidated basis. Cash Position: Cash, cash equivalents and marketable securities were $356.6 million as of December 31, 2022. Subsequent to December 31, 2022, we raised $48.4 million in net proceeds through our “At-the-market” (ATM) program. We believe our current cash, cash equivalents and marketable securities are sufficient to fund our planned operations into 2025. Researchand Development (R&D) expenses: R&D expenses were $30.2 million for the fourth quarter of 2022, compared to $13.8 million for the fourth quarter of 2021. R&D expenses were $87.7 million for the year ended December 31, 2022, compared to $58.5 million for the year ended December 31, 2021. General and Administrative (G&A) expenses: G&A expenses were $8.4 million for the fourth quarter of 2022, compared to $4.0 million for the fourth quarter of 2021. G&A expenses were $25.4 million for the year ended December 31, 2022, compared to $8.7 million for the year ended December 31, 2021. Net loss: Net loss was $35.2 million for the fourth quarter of 2022, compared to $17.8 million for the fourth quarter of 2021. Net loss was $108.4 million for the year ended December 31, 2022, compared to $83.7 million for the year ended December 31, 2021. Conference Call Information Ventyx will host a conference call today at 4:30 p.m. ET to discuss its fourth quarter and full year 2022 financial results and provide a corporate update. To participate in the conference call, please dial (800) 343-4136 (U.S.) or (203) 518-9783 (international) and reference passcode VTYXQ422. A live audio webcast will be available in the Investors section of the company’s website at . A recording of the webcast will be available for thirty days following the call. About Ventyx Biosciences Ventyx is a clinical-stage biopharmaceutical company focused on developing innovative oral medicines for patients living with autoimmune and inflammatory disorders. We believe our ability to efficiently discover and develop differentiated drug candidates will allow us to address important unmet medical need with novel oral therapies that can shift immunology markets from injectable to oral drugs. Our current pipeline includes three internally discovered clinical programs targeting TYK2, S1P1R and NLRP3, positioning us to become a leader in the development of oral immunology therapies. Ventyx is headquartered in Encinitas, California. For more information about Ventyx, please visit . Forward-Looking Statements Ventyx cautions you that statements contained in this press release regarding matters that are not historical facts are forward-looking statements. These statements are based on Ventyx’s current beliefs and expectations. Such forward-looking statements include, but are not limited to, statements regarding: management’s beliefs regarding the potential of Ventyx’s product candidates; the anticipated timing of commencement, enrollment and completion of clinical trials for Ventyx’s product candidates; the anticipated timing for releasing topline data for clinical trials of Ventyx’s product candidates; the anticipated timing for providing an update on VTX958 ER tablet development; and the expected timeframe for funding Ventyx’s operating plan with current cash, cash equivalents and marketable securities. The inclusion of forward-looking statements should not be regarded as a representation by Ventyx that any of its plans will be achieved. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in Ventyx’s business, including, without limitation, potential delays in the commencement, enrollment and completion of clinical trials; Ventyx’s dependence on third parties in connection with product manufacturing, research and preclinical and clinical testing; disruptions in the supply chain, including raw materials needed for manufacturing and animals used in research, delays in site activations and enrollment of clinical trials; the results of preclinical studies and early clinical trials not necessarily being predictive of future results; interim results not necessarily being predictive of final results; the potential of one or more outcomes to materially change as a trial continues and more patient data become available and following more comprehensive audit and verification procedures; regulatory developments in the United States and foreign countries; unexpected adverse side effects or inadequate efficacy of Ventyx’s product candidates that may limit their development, regulatory approval and/or commercialization, or may result in recalls or product liability claims; Ventyx’s ability to obtain and maintain intellectual property protection for its product candidates; the use of capital resources by Ventyx sooner than expected; disruption to Ventyx’s operations from the ongoing global outbreak of the COVID-19 pandemic, or from the ongoing military conflict in Ukraine, including clinical trial delays; and other risks described in Ventyx’s prior press releases and Ventyx’s filings with the Securities and Exchange Commission (SEC), including in Part I, Item 1A (Risk Factors) of Ventyx’s Annual Report on Form 10-K for the year ended December 31, 2022 filed on or about the date hereof, and any subsequent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and Ventyx undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Investor Relations Contact Patti Bank Managing Director ICR Westwicke (415) 513-1284 IR@ventyxbio.com Ventyx Biosciences, Inc. Condensed Consolidated Statements of Operations and Comprehensive Loss (in thousands, except share and per share amounts) Three months ended December 31, Year ended December 31, 2022 2021 2022 2021 Operating expenses: Research and development $ 30,185 $ 13,824 $ 87,738 $ 58,481 General and administrative 8,386 4,002 25,398 8,666 Total operating expenses 38,571 17,826 113,136 67,147 Loss from operations (38,571 ) (17,826 ) (113,136 ) (67,147 ) Other (income) expense: Interest income (3,185 ) (60 ) (4,669 ) (78 ) Other (income) expense (172 ) 2 (41 ) 51 Interest expense - related party — — — 99 Change in fair value of notes and derivative - related party — — — 11,051 Change in fair value of Series A tranche liability — — — 5,476 Total other (income) expense (3,357 ) (58 ) (4,710 ) 16,599 Net loss (35,214 ) (17,768 ) (108,426 ) (83,746 ) Deemed dividend — — — (1,552 ) Net loss attributable to common shareholders $ (35,214 ) $ (17,768 ) $ (108,426 ) $ (85,298 ) Net loss $ (35,214 ) $ (17,768 ) $ (108,426 ) $ (83,746 ) Unrealized gain (loss) on marketable securities 181 (75 ) (1,023 ) (69 ) Foreign currency translation 8 — (42 ) 11 Comprehensive loss $ (35,025 ) $ (17,843 ) $ (109,491 ) $ (83,804 ) Net loss per share attributable to common shareholders, basic and diluted $ (0.62 ) $ (0.44 ) $ (2.07 ) $ (6.65 ) Shares used to compute basic and diluted net loss per share attributable to common shareholders 56,723,942 40,768,229 52,471,003 12,825,598 Ventyx Biosciences, Inc. Selected Consolidated Balance Sheet Data (in thousands) December 31, December 31, 2022 2021 Cash, cash equivalents and marketable securities $ 356,613 $ 286,724 Working capital 314,329 250,737 Total assets 371,400 291,482 Total liabilities 17,505 12,283 Accumulated deficit (226,225 ) (117,799 ) Total stockholders' equity 353,895 279,199

Nes-Ziona, Israel, Feb. 15, 2023 (GLOBE NEWSWIRE) -- Enlivex Therapeutics Ltd. (Nasdaq: ENLV, the “Company”), a clinical-stage macrophage reprogramming immunotherapy company, today announced the issuance of an Israeli patent, numbered 284985, entitled, “Combination Immune Therapy and Cytokine Control Therapy for Cancer Treatment.” The patent provides added intellectual property protection in Israel into at least 2037, with claims covering the use of for Allocetra™ for prevention or amelioration of cytokine storms in cancer patients receiving CAR-T therapy, as well as in patients whose cytokine storms result from infectious diseases or non-infectious sources. Oren Hershkovitz, PhD, CEO of Enlivex commented, “We are pleased with the continued buildup of our comprehensive intellectual property portfolio for Allocetra™.” Infectious diseases covered by this patent include influenza, bird flu, severe acute respiratory syndrome (SARS), Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (HLH), sepsis, gram-negative sepsis, malaria, an Ebola virus, a variola virus, a systemic Gram-negative bacterial infection, or Jarisch-Herxheimer syndrome, or wherein said non-infectious stimuli, condition, or syndrome comprises is hemophagocytic lymphohistiocytosis (HLH), sporadic HLH, macrophage activation syndrome (MAS), chronic arthritis, systemic Juvenile Idiopathic Arthritis (sJIA), Still’s Disease, a Cryopyrin-associated Periodic Syndrome (CAPS), Familial Cold Auto-inflammatory Syndrome (FCAS), Familial Cold Urticaria (FCU), Muckle-Well Syndrome (MWS), Chronic Infantile Neurological Cutaneous and Articular (CINCA) Syndrome, a cryopyrinopathy comprising inherited or de novo gain of function mutations in the NLRP3 gene, a hereditary auto-inflammatory disorder, acute pancreatitis, severe burns, a trauma, an acute respiratory distress syndrome, an immunotherapy, a monoclonal antibody therapy, secondary to drug use, is secondary to inhalation of toxins, a lipopolysaccharide (LPS), a Gram-positive toxins, fungal toxins, glycosylphosphatidylinositol (GPI), or modulation of RIG-1 gene expression. CAR T-cells are T-cells that have been genetically modified to include a receptor that allows them to specifically target and destroy cancer cells. While certain CAR T-cell treatments were recently approved by the FDA in several cancer indications, such treatments have been associated in many patients with a side effect named cytokine release syndrome, which describes a collection of potentially severe or life-threatening symptoms that stem from over-activation of immune pathways. Preclinical data indicate that Allocetra™ has the potential to prevent or ameliorate cytokine release syndrome associated with CAR T-cell therapies. ABOUT ALLOCETRA™Allocetra™ is being developed as a universal, off-the-shelf cell therapy designed to reprogram macrophages into their homeostatic state. Diseases such as solid cancers, sepsis, and many others reprogram macrophages out of their homeostatic state. These non-homeostatic macrophages contribute significantly to the severity of the respective diseases. By restoring macrophage homeostasis, Allocetra™ has the potential to provide a novel immunotherapeutic mechanism of action for life-threatening clinical indications that are defined as "unmet medical needs", as a stand-alone therapy or in combination with leading therapeutic agents. ABOUT ENLIVEX Enlivex is a clinical stage macrophage reprogramming immunotherapy company developing Allocetra™, a universal off-the-shelf cell therapy designed to reprogram macrophages into their homeostatic state. Resetting non-homeostatic macrophages into their homeostatic state is critical for immune system rebalancing and resolution of life-threatening conditions. For more information, visit http://www.enlivex.com. Safe Harbor Statement: This press release contains forward-looking statements, which may be identified by words such as “expects,” “plans,” “projects,” “will,” “may,” “anticipates,” “believes,” “should,” “would”, “could,” “intends,” “estimates,” “suggests,” “has the potential to” and other words of similar meaning, including statements regarding expected cash balances, market opportunities for the results of current clinical studies and preclinical experiments, the effectiveness of, and market opportunities for, ALLOCETRATM programs. All such forward-looking statements are made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Investors are cautioned that forward-looking statements involve risks and uncertainties that may affect Enlivex’s business and prospects, including the risks that Enlivex may not succeed in generating any revenues or developing any commercial products; that the products in development may fail, may not achieve the expected results or effectiveness and/or may not generate data that would support the approval or marketing of these products for the indications being studied or for other indications; that ongoing studies may not continue to show substantial or any activity; and other risks and uncertainties that may cause results to differ materially from those set forth in the forward-looking statements. The results of clinical trials in humans may produce results that differ significantly from the results of clinical and other trials in animals. The results of early-stage trials may differ significantly from the results of more developed, later-stage trials. The development of any products using the ALLOCETRATM product line could also be affected by a number of other factors, including unexpected safety, efficacy or manufacturing issues, additional time requirements for data analyses and decision making, the impact of pharmaceutical industry regulation, the impact of competitive products and pricing and the impact of patents and other proprietary rights held by competitors and other third parties. In addition to the risk factors described above, investors should consider the economic, competitive, governmental, technological and other factors discussed in Enlivex’s filings with the Securities and Exchange Commission, including in the Company’s most recent Annual Report on Form 20-F filed with the Securities and Exchange Commission. The forward-looking statements contained in this press release speak only as of the date the statements were made, and we do not undertake any obligation to update forward-looking statements, except as required under applicable law. ENLIVEX CONTACT Shachar Shlosberger, CFO Enlivex Therapeutics, Ltd. shachar@enlivexpharm.com INVESTOR RELATIONS CONTACTEric RibnerLifeSci Advisorseric@lifesciadvisors.com

– ARCALYST® (rilonacept) Q4 2022 and full-year 2022 net product revenue of $39.9 million and $122.5 million, respectively (unaudited) – – 2 of 3 cohorts enrolled in KPL-404 Phase 2 trial in rheumatoid arthritis; data expected in 1H 2024 – – Cash reserves expected to fund operations into at least 2025 – HAMILTON, Bermuda, Jan. 09, 2023 (GLOBE NEWSWIRE) -- Kiniksa Pharmaceuticals, Ltd. (Nasdaq: KNSA) (Kiniksa), a biopharmaceutical company with a pipeline of immune-modulating assets designed to target a spectrum of cardiovascular and autoimmune diseases, today provided a corporate and portfolio update. “Kiniksa continues to optimize its portfolio and is well-positioned for both near- and long-term growth. We plan to advance our cardiovascular franchise through continued ARCALYST commercial execution in recurrent pericarditis and the pursuit of collaborative study agreements with mavrilimumab. Additionally, we are building an autoimmune franchise initially through the clinical trial of KPL-404, our CD40 antagonist, in rheumatoid arthritis,” said Sanj K. Patel, Chairman and Chief Executive Officer of Kiniksa. “These efforts are supported by our profitable ARCALYST collaboration, non-dilutive capital from recent out-licensing transactions, and continued financial discipline. This combination provides cash runway into at least 2025 and allows for continued capital allocation to our existing programs as well as synergistic opportunities.” Corporate Update Kiniksa’s year-end 2022 cash, cash equivalents, and short-term investments of $190.4 million (unaudited) are expected to fund its current operating plan into at least 2025.Kiniksa’s resources are currently focused on growing its cardiovascular franchise through ARCALYST sales and mavrilimumab collaborative study agreements, as well as building an autoimmune franchise, initially with the clinical trial of KPL-404 in rheumatoid arthritis. Portfolio UpdateARCALYST (IL-1α and IL-1β cytokine trap) ARCALYST net product revenue was $39.9 million and $122.5 million for the fourth quarter and full year 2022, respectively (unaudited).Since launch, greater than 800 prescribers have written ARCALYST prescriptions for recurrent pericarditis, with 22% having written prescriptions for 2 or more patients.As of the end of the fourth quarter of 2022, there was a greater than 90% payer approval rate of completed patient cases for recurrent pericarditis.As of the end of the fourth quarter of 2022, the average duration of initial therapy in the commercial setting was approximately 12 months, and approximately 45% of recurrent pericarditis patients who had discontinued ARCALYST therapy restarted treatment.As of the end of the fourth quarter of 2022, approximately 5% of the target 14,000 multiple-recurrent pericarditis patients were actively on ARCALYST treatment.Kiniksa expects to provide full-year 2023 ARCALYST net product revenue guidance with its fourth quarter and full-year 2022 financial results. Portfolio UpdateKPL-404 (monoclonal antibody inhibitor of CD40-CD154 signaling) Kiniksa has completed enrollment of the second and final cohort of the multiple ascending dose portion of the Phase 2 clinical trial of KPL-404 in rheumatoid arthritis. Following completion of this portion of the trial, the proof-of-concept portion will begin. The company expects data from the trial in the first half of 2024. Mavrilimumab (monoclonal antibody inhibitor targeting GM-CSFRα) Kiniksa is pursuing collaborative study agreements to evaluate the potential of mavrilimumab in rare cardiovascular diseases where the granulocyte macrophage colony stimulating factor (GM-CSF) mechanism has been implicated. 41st Annual J.P. Morgan Healthcare ConferenceSanj K. Patel, Chief Executive Officer and Chairman of the Board of Kiniksa will provide a corporate presentation at the 41st Annual J.P. Morgan Healthcare Conference today, Monday, January 9, 2023, at 1:30 p.m. Pacific Time (4:30 p.m. Eastern Time). A live webcast of Kiniksa’s presentation will be accessible through the Investors & Media section of the company’s website at www.kiniksa.com. A replay of the webcast will also be available on Kiniksa’s website within approximately 48 hours after the event. About KiniksaKiniksa is a biopharmaceutical company focused on discovering, acquiring, developing, and commercializing therapeutic medicines for patients suffering from debilitating diseases with significant unmet medical need. Kiniksa’s portfolio of immune-modulating assets, ARCALYST, KPL-404, and mavrilimumab, are based on strong biologic rationale or validated mechanisms, target a spectrum of underserved cardiovascular and autoimmune conditions, and offer the potential for differentiation. For more information, please visit www.kiniksa.com. About ARCALYSTARCALYST is a weekly, subcutaneously injected recombinant dimeric fusion protein that blocks interleukin-1 alpha (IL-1α) and interleukin-1 beta (IL-1β) signaling. ARCALYST was discovered by Regeneron and is approved by the U.S. Food and Drug Administration (FDA) for recurrent pericarditis, cryopyrin-associated periodic syndromes (CAPS), including Familial Cold Autoinflammatory Syndrome and Muckle-Wells Syndrome, and deficiency of IL-1 receptor antagonist (DIRA). The FDA granted Breakthrough Therapy designation to ARCALYST for the treatment of recurrent pericarditis in 2019 and Orphan Drug designation to ARCALYST for the treatment of pericarditis in 2020. The European Commission granted Orphan Drug Designation to ARCALYST for the treatment of idiopathic pericarditis in 2020. IMPORTANT SAFETY INFORMATION ABOUT ARCALYST ARCALYST may affect your immune system and can lower the ability of your immune system to fight infections. Serious infections, including life-threatening infections and death, have happened in patients taking ARCALYST. If you have any signs of an infection, call your doctor right away. Treatment with ARCALYST should be stopped if you get a serious infection. You should not begin treatment with ARCALYST if you have an infection or have infections that keep coming back (chronic infection).While taking ARCALYST, do not take other medicines that block interleukin-1, such as Kineret® (anakinra), or medicines that block tumor necrosis factor, such as Enbrel® (etanercept), Humira® (adalimumab), or Remicade® (infliximab), as this may increase your risk of getting a serious infection.Talk with your doctor about your vaccine history. Ask your doctor whether you should receive any vaccines before you begin treatment with ARCALYST.Medicines that affect the immune system may increase the risk of getting cancer.Stop taking ARCALYST and call your doctor or get emergency care right away if you have any symptoms of an allergic reaction.Your doctor will do blood tests to check for changes in your blood cholesterol and triglycerides.Common side effects include injection-site reactions (which may include pain, redness, swelling, itching, bruising, lumps, inflammation, skin rash, blisters, warmth, and bleeding at the injection site), upper respiratory tract infections, joint and muscle aches, rash, ear infection, sore throat, and runny nose. For more information about ARCALYST, talk to your doctor and see the Product Information. About KPL-404KPL-404 is an investigational humanized monoclonal antibody that is designed to inhibit CD40-CD154 (CD40 ligand) interaction, a key T-cell co-stimulatory signal critical for B-cell maturation and immunoglobulin class switching and Type 1 immune responses. Kiniksa believes disrupting the CD40-CD154 interaction is an attractive approach to address multiple autoimmune disease pathologies. About MavrilimumabMavrilimumab is an investigational fully human monoclonal antibody that blocks activity of GM-CSF by specifically binding to the alpha subunit of the GM-CSF receptor (GM-CSFRα). Phase 2 clinical trials of mavrilimumab in rheumatoid arthritis and giant cell arteritis achieved their primary and secondary endpoints with statistical significance. Kiniksa is evaluating the development of mavrilimumab in rare cardiovascular diseases where the GM-CSF mechanism has been implicated. Forward-Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” 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 press release that do not relate to matters of historical fact should be considered forward-looking statements, including without limitation, statements regarding: our plan to (i) advance our cardiovascular franchise through continued ARCALYST commercial execution in recurrent pericarditis and the pursuit of collaborative study agreements with mavrilimumab and (ii) build an autoimmune franchise, initially with the clinical trial of KPL-404 in rheumatoid arthritis; our expectation that (i) the proof-of-concept portion of the Phase 2 clinical trial of KPL-404 in rheumatoid arthritis will begin after completion of the multiple ascending dose portion of such trial, and (ii) we will report data from such Phase 2 clinical trial in the first half of 2024; our pursuit of collaborative study agreements to evaluate the potential of mavrilimumab in rare cardiovascular diseases where the GM-CSF mechanism has been implicated; our expectation to provide full-year 2023 ARCALYST net product revenue guidance with our fourth quarter and full-year 2022 financial results; our expectation about our cash reserves funding our current operating plan into at least 2025; our beliefs about the mechanisms of action of our product candidates and potential impact of their approach, including that using KPL-404 to disrupt the CD40-CD154 interaction is an attractive approach to address multiple autoimmune disease pathologies; and our belief that all of our product candidates offer the potential for differentiation. These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including without limitation, the following: delays or difficulty in enrollment of patients in, and activation or continuation of sites for, our clinical trials; delays or difficulty in completing our clinical trials as originally designed; potential for changes between final data and any preliminary, interim, top-line or other data from clinical trials; our inability to replicate results from our earlier clinical trials or studies; impact of additional data from us or other companies, including the potential for our data to produce negative, inconclusive or commercially uncompetitive results; potential undesirable side effects caused by our products and product candidates; our inability to demonstrate safety and efficacy to the satisfaction of applicable regulatory authorities; potential for applicable regulatory authorities to not accept our filings, delay or deny approval of any of our product candidates or require additional data or trials to support approval; inability to successfully execute on our commercial strategy for ARCALYST; our reliance on third parties as the sole source of supply of the drug substance and drug product used in our products and product candidates; our reliance on Regeneron as the sole manufacturer of ARCALYST; raw material, important ancillary product and drug substance and/or drug product shortages; our reliance on third parties to conduct research, clinical trials, and/or certain regulatory activities for our product candidates; complications in coordinating requirements, regulations and guidelines of regulatory authorities across jurisdictions for our clinical trials; the impact of the COVID-19 pandemic and any subsequent pandemic and measures taken in response to such pandemics on our business and operations as well as the business and operations of our manufacturers, CROs upon whom we rely to conduct our clinical trials, and other third parties with whom we conduct business or otherwise engage, including the FDA and other regulatory authorities; changes in our operating plan and funding requirements; and existing or new competition. These and other important factors discussed in our filings with the U.S. Securities and Exchange Commission, including under the caption “Risk Factors” contained therein, could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. Except as required by law, we disclaim any intention or obligation to update or revise any forward-looking statements. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release. ARCALYST® is a registered trademark of Regeneron Pharmaceuticals, Inc. All other trademarks are the property of their respective owners. Every Second Counts! ® Kiniksa Investor and Media ContactRachel Frank(339) 970-9437rfrank@kiniksa.com