#1So sanofi Immunology Investor Event Epidemiology Cambridge, MA March 29, 2022#2Dupixent: Atopic Dermatitis Adult 18+ Number of patients (thousands) Prevalence Treated 5,722 8,174 7,136 5,231 1,038 11,991 Moderate-to-Severe 2,638 2,997 595 6,230 Biologics eligible 1,675 1,121 222 3,018 Most in need 301 189 100 590 0 2,000 4,000 6,000 US 1,416 16,726 Moderate-to-Severe uncontrolled sanofi 8,000 10,000 12,000 14,000 16,000 18,000 Europe(1) Japan Treated with multiple systemic steroids or one immunosuppressant or phototherapy(2) Source: Sanofi analysis (1) Germany, France, Italy, Spain & United Kingdom. (2) For EU, patients who have inadequate response or intolerant to immunosuppressants 2 Immunology Investor Event#3Dupixent: Atopic Dermatitis Adolescents 12-17yo Prevalence Treated Moderate-to-Severe Number of patients (thousands) 2,497 2,072 968 1,015 1,983 Biologics eligible 389 345 734 2,297 2,538 4,369 5,035 Moderate-to-Severe uncontrolled sanofi Most in need 166 92 258 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 Treated with multiple systemic steroids or one immunosuppressant or phototherapy (2) US Europe (1) Source: Sanofi analysis (1) Germany, France, Italy, Spain & United Kingdom. (2) For Europe, patients who have inadequate response or intolerant to immunosuppressants 3 Immunology Investor Event#4Dupixent: Atopic Dermatitis Child 6-11yo Number of patients (thousands) Prevalence Treated Moderate-to-Severe Uncontrolled Moderate-to-Severe 2,457 1,985 718 894 1,612 320 Biologics eligible 88 74 162 2,305 2,853 4,290 5,310 sanofi Assuming eligibility limited to severe uncontrolled in pediatric indications. EU Biologic eligible was derived from moderate-to-severe 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 US Europe(1) Source: Sanofi analysis (1) Germany, France, Italy, Spain & United Kingdom. 4 Immunology Investor Event#5Dupixent: Atopic Dermatitis Child <6yo Number of patients (thousands) Prevalence Treated Moderate-to-Severe 1,700 2,429 675 777 1,452 Uncontrolled 261 Moderate-to-Severe Biologics eligible 75 80 155 0 2,594 5,023 1,815 3,515 sanofi Assuming eligibility limited to severe uncontrolled in pediatric indications. EU Biologic eligible was derived from moderate-to-severe 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 Source: Sanofi analysis (1) Germany, France, Italy, Spain & United Kingdom. 5 Immunology Investor Event US Europe(1)#6Dupixent: Asthma 12+ Prevalence Number of patients (thousands) 23,500 18,420 4,900 46,820 Treated 1,600 1,790 600 3,990 Biologics eligible 900 800 200 1,900 42,000 43,000 44,000 45,000 46,000 47,000 0 1,000 2,000 3,000 US Europe(1) Japan Source: Sanofi analysis ICS: Inhaled Corticosteroids; OCS: Oral Corticosteroids (1) Germany, France, Italy, Spain & United Kingdom (2) For Europe, severe with persistent use of ICS or OCS. (3) For EU, severe uncontrolled or OCS dependent Immunology Investor Event 6 Moderate to severe with persistent use of medium to high dose ICS or OCS use or biologic(2) Uncontrolled despite persistent use of medium to high dose ICS + ≥1 controller or OCS(3) sanofi#7Dupixent: Asthma 6-11yo Prevalence Number of patients (thousands) Treated 201 180 381 Biologics eligible 75 26 101 2,365 1,253 3,618 Moderate to severe with persistent use of medium to high dose ICS or OCS use or biologic 0 500 2,000 2,500 3,000 3,500 4,000 US Europe(1) Source: Sanofi analysis ICS: Inhaled Corticosteroids; OCS: Oral Corticosteroids (1) Germany, France, Italy, Spain & United Kingdom (2) For Europe, severe uncontrolled type 2 7 Immunology Investor Event Uncontrolled despite persistent use of medium to high dose ICS + ≥1 controller or OCS(2) sanofi#8Dupixent: Chronic Obstructive Pulmonary Disease Number of patients (thousands) Prevalence 10,052 10,753 2,084 22,889 Treated 8,367 8,700 1,473 18,540 GOLD D 1,581 1,222 207 3,010 Eosinophilic population 300 200 50 550 нн 0 2,000 10,000 18,000 20,000 22,000 24,000 US Europe (1) Japan Source: Sanofi analysis sanofi COPD with eosinophilic phenotype uncontrolled with current SoC (patients that are on triple therapy among GOLD D) SoC: Standard of Care; GOLD criteria: Global Initiative for Chronic Obstructive Lung Disease - Group D: high risk (≥2 exacerbations/year, or one+ requiring hospitalization) and more symptoms (mMRC≥ 2 or CAT≥ 10) (1) Germany, France, Italy, Spain & United Kingdom 8 Immunology Investor Event#9sanofi Dupixent: Chronic Rhinosinusitis with Nasal Polyposis Prevalence(1) Number of patients (thousands) Treated 227 Moderate-to-Severe 484 407 147 191 147 485 Biologics eligible 90 74 43 207 423 214 848 907 Inadequately controlled CRSWNP(3) Most in need 55 47 16 118 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 Patients uncontrolled despite prior surgery US Europe (2) Japan Source: Sanofi analysis (1) 18+ population (2) Germany, France, Italy, Spain & United Kingdom (3) For Europe, patients with severe CRSWNP inadequately controlled on systemic corticosteroids and / or surgery 9 Immunology Investor Event#10sanofi Dupixent: Chronic Rhinosinusitis Sans Nasal Polyposis Number of patients (thousands) Diagnosed CRSSNP Patients(1) Diagnosed type 2 CRSSNP Patients Most in need 130 Source: Sanofi analysis (1) 12+ population 10 Immunology Investor Event 2,500 4,543 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 US#11Dupixent: AFRS Diagnosed CRSWNP & had surgery(1) Number of patients (thousands) AFRS Patients 11 0 10 20 20 Source: Sanofi analysis (1) 12+ population 11 Immunology Investor Event 30 40 40 50 158 60 60 70 80 90 100 110 120 130 140 150 160 US sanofi#12Dupixent: Bullous Pemphigoid Number of patients (thousands) Prevalence (1) 52 Biologic eligible 27 26 10 10 63 89 50 50 19 121 Treated with systemic steroids T T T T T 0 10 20 20 30 40 50 60 70 80 90 100 110 120 130 Source: Sanofi analysis OCS: Oral Corticosteroids (1) 18+ population (2) Germany, France, Italy, Spain & United Kingdom 12 Immunology Investor Event US Europe (2) Japan sanofi#13Dupixent: Prurigo Nodularis Number of patients (thousands) Prevalence(1) 298 Biologic eligible 74 70 27 171 282 107 687 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 US Europe (2) Japan Source: Sanofi analysis (1) 18+ population (2) Germany, France, Italy, Spain & United Kingdom 13 Immunology Investor Event sanofi Patients inadequately controlled by topical corticosteroids#14Dupixent: Chronic Spontaneous Urticaria Number of patients (thousands) Prevalence (1) Biologic eligible 308 110 418 Source: Sanofi analysis (1) 12+ population 14 Immunology Investor Event 1,500 551 2,051 0 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000 2,200 US Japan Patients uncontrolled on anti-histamines and other SoC (excluding biologics) sanofi#15Dupixent: Chronic Inducible Urticaria (Cold) Number of patients (thousands) Prevalence(1) Biologic eligible 25 0 20 20 Source: Sanofi analysis (1) 12+ population 15 Immunology Investor Event 40 40 60 60 160 80 80 US sanofi Refractory to antihistamines 100 120 140 160 180#16Dupixent: Chronic Pruritis of Unknown Origin Prevalence(1) Treated Number of patients (thousands) Biologic eligible 133 Source: Sanofi analysis (1) 18+ population 16 Immunology Investor Event 259 466 Treated with systemic therapy 0 50 100 150 200 250 300 350 400 450 500 US sanofi#17Dupixent: Eosinophilic Esophagitis 12+ Treated Number of patients (thousands) 159 Severe 48 49 97 0 20 40 40 Source: Sanofi analysis PPI Proton pump inhibitor (1) Germany, France, Italy, Spain & United Kingdom 17 Immunology Investor Event 161 320 T 60 60 80 100 120 140 160 180 200 220 240 260 280 300 320 US Europe(1) Uncontrolled on high dose PPI and topical steroid slurry sanofi