Kiniksa Pharmaceuticals International, Plc · NASDAQ:KNSA

Kiniksa Pharmaceuticals International — European Academy of Dermatology and Venereology 29th Congress 2020

11 slides from Kiniksa Pharmaceuticals International's conference presentation, Oct 29, 2020

1. Slide 1: Vixarelimab reduced pruritus, improved nodules, and was well-tolerated in Prurigo Nodularis

   Vixarelimab reduced pruritus, improved nodules, and was well-tolerated in patients with Prurigo Nodularis in a Phase 2a, randomized, double-blind, placebo-controlled study Top Level Results Howard Sofen1, Robert Bissonnette2, Gil Yosipovitch3, Jonathan Silverberg4, Stephen Tyring5, Mark Lee6, Wei Ji

2. Slide 2: Introduction: Vixarelimab inhibits IL-31 and OSM signaling via a single epitope

   Vixarelimab inhibits IL-31 and OSM signaling Introduction via a single epitope (OSMRβ) IL-31 Receptor Signaling Type II OSM Receptor Signaling • Prurigo nodularis (PN): • Chronic skin disease TH2 cells T cells mast cell Mϕ PMN mast cell • Symmetrically distributed, intensely pruritic OSM IL-31 hyper

3. Slide 3: Multinational, Randomized, Double-Blind, Placebo-Controlled Phase 2a Study

   Multinational, Randomized, Double-Blind, Placebo-Controlled Phase 2a Study Vixarelimab R Screening Period 1:1 Inclusion Criteria Placebo • 18 to 75 years • PN diagnosis; ≥6 months since first PN nodule Loading • ≥10 non-localized nodules (0.5 to 2 cm) Dose • Moderate to severe pruritus 1o & 2o 8-Wee

4. Slide 4: Baseline Demographics and Clinical Characteristics

   Baseline Demographics and Clinical Characteristics Clinical Characteristics at Baseline (n=58) Vixarelimab Placebo Total Demographics (n=23) (n=26) (n=49) Age (Mean Years) 52 64 58 4 42.9 10 8.3 Sex (Male/Female) 10/13 10/16 20/29 3 55.1 Mean PN-IGA 2 2.0 Total Patients WI-NRS Score Race (n=58) Scor

5. Slide 5: Significantly Reduced Weekly-Average WI-NRS versus Placebo

   Vixarelimab Significantly Reduced Weekly-Average WI-NRS versus Placebo Vixarelimab Placebo LS-Mean % Change from Baseline in Median % Change from Baseline in 0% 0% Weekly-average WI-NRS Weekly-Average WI-NRS -10% -10% -20% -20% -30% -29.4% -30% -36.1% -40% -40% -50% * -50.6% -50% * * -60% * * * P=0.

6. Slide 6: Majority With Clinically Meaningful ≥4-Point WI-NRS Reduction

   Vixarelimab: Majority With Clinically Meaningful ≥4-Point WI-NRS Reduction 9-10 8-9 7-8 Vixarelimab Placebo Clinically Meaningful Response in WI-NRS 6-7 Clinically Meaningful Response in WI-NRS 5-6 4-5 % of Vixarelimab Patients with a % of Placebo Patients with a 60% 60% 50% * * 50% 40% * 40% 30% 30

7. Slide 7: Majority With Clinically Meaningful ≥4-Point WI-NRS Reduction in Individual Patients

   Vixarelimab: Majority With Clinically Meaningful ≥4-Point WI-NRS Reduction Individual Patients - Vixarelimab Individual Patients - Placebo 20% 20% % Change in Weekly Average WI-NRS % Change in Weekly Average WI-NRS in Individual Vixarelimab Patients in Individual Placebo Patients 0% 0% 65.4% -20% 47

8. Slide 8: More Patients With Clear/Almost Clear Lesion Score (IGA 0/1)

   Vixarelimab: More Patients With Clear/Almost Clear Lesion Score (IGA 0/1) Vixarelimab 90 Percent of Patients with 100% PN-IGA Score of 0 or 1 ≥4 Point Change in WI-NRS Placebo % of IGA 0-1 Patients with 80 n = 6 of 7 patients 70 80% 60 50 60% * * 40 40% 30 20 20% 10 0 0% BL 2 4 6 8 KPL-716 Placebo T

9. Slide 9: Nodule Resolution at Week 8 in Vixarelimab Recipients (Representative Images)

   Nodule Resolution at Week 8 in Vixarelimab Recipients (Representative Images) Day 1 Week 8 Vixarelimab Recipient 1 WI-NRS = 8.43 WI-NRS = 1.67 PN-IGA = 4 PN-IGA = 1 Vixarilemab Recipient 2 WI-NRS = 9.29 WI-NRS = 0 PN-IGA = 4 PN-IGA = 2

10. Slide 10: Vixarelimab was Well-Tolerated in Prurigo Nodularis Patients

    Vixarelimab was Well-Tolerated in Prurigo Nodularis Patients* Vixarelimab Placebo (n=23) (n=26) Any Adverse Event (n) 82.6% (19) 65.4% (17) Treatment-emergent Adverse Event (TEAE) (n) 82.6% (19) 65.4% (17) Drug-Related TEAE (n) 39.1% (9) 30.8% (8) None of the following occurred during the study: ser

11. Slide 11: Vixarelimab Improved Signs and Symptoms of Prurigo Nodularis in Phase 2a

    Vixarelimab Improved Signs and Symptoms of Prurigo Nodularis in Phase 2a Conclusions: • Primary efficacy endpoint, LS-mean change from baseline weekly-average WI-NRS, was met: – Week 8: -50.6% (vixarelimab) vs. -29.4% (placebo); mean difference 21.1%; p = 0.035 • Median reduction in pruritus (WI-NRS

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