IS TREATED INVESTOR PRESENTATION June 2019 Non Confidential - PowerPoint PPT Presentation

REDEFINING HOW KIDNEY DISEASE IS TREATED INVESTOR PRESENTATION June 2019 Non Confidential

FORWARD LOOKING STATEMENTS This document contains forward-looking information pursuant to applicable securities law. All information that addresses activities or developments that XORTX expects to occur in the future are forward-looking statements. Forward-looking statements are based on the estimates and opinions of management on the date the statements are made. However, they should not be regarded as a representation that any of the plans or objectives will be achieved as actual results may differ materially from those expressed or implied by the forward-looking information set forth in this document due to risks and uncertainties affecting XORTX, including access to capital, the successful completion of clinical trials and receipt of all regulatory approvals. The forward-looking statements in this document are based on a number of assumptions which may prove to be incorrect, including assumptions concerning general business and economic conditions, positive clinical trials and the availability of financing. XORTX assumes no responsibility to update forward-looking statements in this document. 2

KEY HIGHLIGHTS Developing XORTX Clinical development stage products target uric acid lowering, which has clinical stage been shown to have an important clinical effect. assets to treat Significant global market opportunities. kidney disease. Two lead products in development with strong IP and established proof of concept. Two Proprietary XRx-008 for Autosomal Dominant Polycystic Kidney Disease (ADPKD)- Orphan Market. Products XRx-221 for type 2 Diabetic Nephropathy ( T2DN) – Large Market Co-development deal with Teijin Pharma will announce U.S. Phase 2 study of Uric Phase 2a clinical data readout Acid Lowering in type 2 Diabetic Nephropathy Patients; Topline Phase 2a data within 12 months readout - August 2019. Orphan drug Expected initiation of a pivotal registration study in Polycystic Kidney Disease within opportunity in polycystic kidney 12 months. (potentially under an SPA). disease . Experienced XORTX’ Senior team was responsible for oxypurinol and vernakalant development at Management Cardiome Pharma. Team 3

Uric Acid (UA): a Bad Actor in Kidney Disease Lowering Uric Acid Protects Kidney HIGH UA LEVELS PREDICT Diabetic Nephropathy Health, in human clinical trials. Endothelial High Blood NO Depletion Pressure Normalized Blood Pressure Vascular Damage Oxidative Stress Fibrosis Decreased Proteinuria Activation Renin Kidney Angiotensin System Inflammation Decrease and Reversal of Decline in Filtering Capacity Proteinuria Systemic Inflammation Decline of Filtering Capacity 4

Decreasing Uric Acid levels in Diabetes Patients may delay progression to End Stage Renal Disease ( ESRD) XORTX Therapies are designed to delay or reverse progression of kidney disease, to prevent ESRD ESRD – A Life Altering Event • Uric acid hastens loss of • 4 hours per day on dialysis filtering capacity of kidneys • Loss of ability to work full time • Dependence on family Pain and declining health are constant burden • • Shortened survival – only 50% of patients survive two years • A therapy that maintains and extend kidney health can redefine kidney disease treatment in the future. • Diabetic Nephropathy - No drugs are available to treat progressive kidney disease due to uric acid injury. Source: Curr Opin Nephrol Hypertens – 22(2): 185-192, 2013 5

A Strong Patent Portfolio Covers Uric Acid Lowering Agents Use in Progressive Kidney Disease Patent Claims Term US 9,155,740 Method of Use Claims Covering Uric Acid Lowering Agents 2025 (Xanthine Oxidase Inhibitors) in the Treatment of “Diabetic Nephropathy” (Est. GATT extension -4-5 yrs) PCT/US14/30292 Formulations Patent Covering Xanthine Oxidase Inhibitors: 2034 specifically for oxypurinol (XRx-008) PCT/JP2014/05/2154 Composition of matter for XRx-221 (TMX-049) 2034 PCT/JP2014/05/9912 PCT/JP2015/07/1530 PCT/JP2015/07/2153 Use Patent for XRx-221 (TMX-049) in Kidney Disease 2037 PCT/JP2017/04/2429 Note: Orphan Exclusivity adds to product protection in Autosomal Dominant Polycystic Kidney Disease (ADPKD) 6

Competitive Landscape Analysis & Well differentiated Compared to Landscape Current Agents are Ineffective at Best CLASS IP ADVANTAGES LIMITATIONS Uricosurics Varied Decrease uric acid absorption/ reuptake Inappropriate: Increase kidney stone formation Uricase Off Patent Acute IV use Cannot be used chronically Xanthine Oxidase Inhibitors Allopurinol Off Patent Decreases UA production and serum uric acid Only approved for GOUT ~2-3 mg/dL. Only works well in ~28% of individuals Well Characterized Modest effect (~2-3 mg/dL) Acceptable side effect profile Side effects: Rash, Liver Enzymes, Kidney Febuxostat 2019 Higher Potency -decreases UA production and Only approved for GOUT and Cancer serum uric acid ~2-6 mg/dL. * Recent FDA Boxed Warning Oxypurinol 2034 Decreases UA production ~2-3 mg/dL Modest effect (free acid) Improved tolerability Poor Bioavailability Comparable efficacy to allopurinol XRx-008 2034 Decreases UA production ~2-3 mg/dL Improved tolerability 3X increase in Bioavailability XRx-221 2034, 2037 High Potency (~3-6 mg/dL) None observed to date (TMX-049) Improved tolerability Clean Safety Profile 7

Two Significant Market Opportunities Progressive Kidney Disease Opportu tunity ty #2: Opportu tunity ty #1: Diabeti etic Kidney ey Disea ease e – Ph Ph II II Orphan Disease - PhIII XRx-221 in T2DN XRx-008 in (ADPDK) DK) U.S. ~ 10,000,000 Individuals U.S. ~150,000 Individuals ~100,000,000 Individuals Worldwide Worldwide ~1,500,000 Individuals Phase 2a Topline August 2019 Registration Study Initiation 2020 Phase 2b Initiation 2020 Phase 3 - Data Readout 2022 Phase 3a & 3b Topline August 2025 & 26 U.S. Marketing Approval 2023/4 2027 U.S. Market Approval Estimated Peak Sales – USA → $1.8 B/yr Estimated Peak Sales – USA → $2.4 B/yr Worldwide → $4 B/yr Worldwide → $5 B/yr 8

XRx-008 in Polycystic tic Kidney Diseas ase – (PKD) XRx-008: A Novel Formulation of Oxypurinol • XRx-008 - a proprietary formulation of Oxypurinol with 3X increased bioavailability – Wholly owned by XORTX Therapeutics Inc. and developed “In - house” • Increased tolerability increases compliance and supports chronic dosing • Increased bioavailability increases oral dosing range • Independent Phase 2 clinical trials show Oxypurinol Lowers uric acid, Improves vascular function • Negotiating Phase III Registration Trial with FDA and Company also intends to seek Special Protocol Assessment • XRX-008 - pre-IND work and FDA Investigational New Drug application (IND) meeting completed, Orphan Drug Designation ( ODD) application initiated. • Orphan Drug Classification: ~120,000 U.S. patients 9

XRx-008: Autosomal Dominant Polycystic Kidney Disease (ADPKD) Development Timeline: ** Planning to Initiate Pivotal Study under SPA in first half of 2020 ** 2019 2020 2021 2022 2023 2024 GMP Mfg. (9 months) Finalize IND Finalize ODD BA Study Protocol/SPA Ph III Ph3 Pivotal Study under SPA - (30 months) NDA filing ( Accelerated Review) GMP – Good Manufacturing Process Standards IND- Investigational New Drug ODD- Orphan Drug Designation Marketing BA – Bio-availablity Study in Man Approval SPA – Special Protocol Assessment NDA – New Drug Application for marketing 11

XRx-221 (TMX-049) to treat Progressive Diabetic Kidney Disease XRx-221 - a proprietary “next generation” Xanthine OxidoReductase Inhibitor - Type 2 Diabetic Nephropathy (T2DN) • High Potency inhibits production of uric acid, thus decreasing and maintaining SUA levels at low-normal target range • Reduced metabolism suggests excellent tolerability • Excellent Clinical efficacy and safety record in >150 patients • Phase 2a T2DN study topline results due August 2019 –UACR 1’ endpoint (Under US FDA IND) • Co-Development Agreement between XORTX and Teijin for Global Rights • “Next Generation” -Xanthine OxidoReductase Inhibitor - Phase 2b ready asset under XORTX’s DN patent (except Japan) 11

XRx-221 (TMX-049) Development Timeline Development Timeline: 2019 2019 2020 2020 2021 2021 2022 2022 2023 2023 2024 2024 2025 2025 I---Phase 2a-- ---I Phase 2a results Phase 2b Proof of Concept- (400 patients) Ph2b results DDI Study FDA Meeting QT/QTc (if necessary) End of Ph2b **Pilot Adolescent Study Pilot results I-------Phase 3a Pivotal Study - (1200 patients) I--------Phase 3b Pivotal Study (1200 pts)----------I Pilot results may NDA Permit early NDA Filing DDI – Drug Drug Interaction Study Filing NDA – New Drug Application for marketing 2025 14

CAPITAL STRUCTURE Market Capitalization ~$15 million Common Shares Outstanding 62,919,691 Warrants 4,004,740 Options 2,674,000 Fully-diluted Shares Outstanding 69,598,431 Public Listings XRX : CSE | XRTXF : OTCQB Longer term plan for NASDAQ listing Description of Shares Held: Mgmt & Insiders → 26% ~54/63 Million shares closely held Angels → 29% & estimated free trading float ~ 7M shares Institutional → 2% 13