Milestone Pharmaceuticals : Corporate Presentation

Company Overview

June 6, 2024

Forward Looking Statement

The Presentation contains forward-looking statements within the meaning of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, as amended. Words such as ''aim,'' ''anticipate,'' ''assume,'' ''believe,'' ''contemplate,'' ''continue,'' ''could,'' ''design,'' ''due,'' ''estimate,'' ''expect,'' ''goal,'' ''intend,'' ''may,'' ''objective,'' ''plan,'' ''predict,'' ''positioned,'' ''potential,'' ''project,'' ''seek,'' ''should,'' ''target,'' ''will,'' ''would'' (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify

forward-looking statements. These forward- looking statements are based on Milestone's expectations and assumptions as of the date of this Presentation. Each of these forward-looking statements involves risks and uncertainties. Actual results may differ materially from these forward-looking statements. Forward-looking statements contained in this Presentation include statements regarding (i) the design, progress, timing, scope and results of the etripamil clinical trials in PSVT and AFib-RVR, (ii) the potential efficacy, safety and tolerability of CARDAMYST for PSVT and etripamil for AFib-RVR, (iii) the potential of CARDAMYST to deliver a new PSVT therapeutic option to market, (iv) plans relating to commercializing CARDAMYST, if approved, including the geographic areas of focus and sales strategy, (v) the potential market size and the rate and degree of market acceptance of CARDAMYST (etripamil) and any future product candidates and the implementation of Milestone's business model and strategic plans for its business, etripamil and any future product candidates (vi) Milestone's expected cash runway and (vii) potential royalty payments. Important factors that could cause actual results to differ materially from those in the forward-looking statements include, but are not limited to, the risks inherent in biopharmaceutical product development and clinical trials, including the lengthy and uncertain regulatory approval process, uncertainties as to whether our NDA filing for CARDAMYST will be approved by the FDA, uncertainties related to the timing of initiation, enrollment, completion and evaluation of clinical trials, including the RAPID and ReVeRA trials, and whether the clinical trials will validate the safety and efficacy of CARDAMYST for PSVT, etripamil for AFib-RVR or other indications, among others, as well as risks related to pandemics and public health emergencies, including those related to COVID-19, and risks related the sufficiency of our capital resources and our ability to raise additional capital. These and other risks are set forth in Milestone's filings with the U.S. Securities and Exchange Commission, including in its annual report on Form 10-K for the year ended December 31, 2023, under the caption "Risk Factors", as such discussion may be updated in future filings we make with the SEC. Except as required by law, Milestone assumes no obligation to update any forward- looking statements contained herein to reflect any change in expectations, even as new information becomes available.

This Presentation contains trademarks, trade names and service marks of other companies, which are the property of their respective owners. Certain information contained in this Presentation and statements made orally during this Presentation relate to or is based on studies, publications, surveys and other data obtained from third-party sources and Milestone's own internal estimates and research. While Milestone believes these third-party studies, publications, surveys and other data to be reliable as of the date of the Presentation, it has not independently verified, and makes no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, no independent sources has evaluated the reasonableness or accuracy of Milestone's internal estimates or research and no reliance should be made on any information or statements made in this Presentation relating to or based on such internal estimates and research.

CARDAMYSTTM (etripamil) nasal spray is an investigational new drug, which is not approved for commercial distribution in the United States.

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Milestone Pharmaceuticals:

Aspiring to Give Patients Control over Common Heart Conditions

	Empowering Patients			PSVT			AFib-RVR
•	Self-Treat Common Arrhythmias		•	Commercial Launch Preparation		•	Market Expansion Opportunity
CARDAMYSTTM (etripamil)		NDA accepted May 2024,		End of Phase 2 Meeting
	nasal spray: investigational			PDUFA action date Mar 2025			expected mid-2024
	novel calcium channel		•	Successful Phase 3 -Published		•	FDA Phase 3 study
	blocker
			in The Lancet			guidance - 1Q 2024
•	Fast-acting,well-tolerated,		•	Experienced leadership		•	Positive Phase 2 ReVeRA
	portable, on-demand
			driving commercialization			Study - AHA Presentation
•	Shift from Emergency						and published in Circulation
	Department to patient						AE - Nov 2023
	self-management

PSVT = Paroxysmal Supraventricular Tachycardia; AFib-RVR = Atrial Fibrillation with Rapid Ventricular Rate; NDA = New Drug Application; AHA - American Heart Association. Citations: Stambler B et al, The Lancet (2023); Camm AJ et al, Circulation: Arrhythmia & Electrophysiology (2023)

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Atrial Arrhythmias with a Common Patient Burden & Cardiac Target

BURDEN: Patients with PSVT & AFib-RVR report

marked, often-disabling symptoms

PSVT	AFib-RVR
(AVNRT and AVRT)	(a subset of AFib)
Regular rapid heart rate	Irregular rapid heart rate
Commonly 150 - 250 bpm	Commonly 100 - 175 bpm

Episode frequency and duration is highly variable; occurring without warning

Common	Heart palpitations	Chest pressure or pain
Symptoms	Shortness of breath	Fatigue
Include	Light-headedness	Anxiety / Loss-of-control

PSVT = Paroxysmal Supraventricular Tachycardia; AFib-RVR = Atrial Fibrillation with Rapid Ventricular Rate Sources: adapted from https://en.ecgpedia.org/index.php?title=Supraventricular_Rhythms, accessed 2/2021

TARGET: PSVT & AFib-RVR

Rely on AV Nodal Properties

Atrial Fibrillation

(multiple atrial

wavelets)

SA Node

AV Node

AV Nodal	AV Reentrant
Reentrant Tachycardia	Tachycardia
(AVNRT)	(AVRT)

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Current Treatment of Acute Attacks in the Emergency

Department are Burdensome and Costly

For many patients, physicians and payers:

• Time-consuming,disruptive
• Often results in a hospital admission
• Expensive use of healthcare system resources

Need for simple, fast-acting treatment, reduce trips to ED and calls to physicians

ED = Emergency Department

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PSVT and AFib-RVR Populations in the US

	PSVT	Atrial Fibrillation
Total Patients (2030)	2.6 Million3	10 Million1
Discharged ED Visits	145 Thousand	785 Thousand
& Hospital Admissions (2016)2
Target Addressable Market (2030)	1.0-1.6 Million5	~3-4 Million4
Patient Population

Source(s): 1. Colilla et al., Am. J. Cardiol. 2013, 112(8), 1142-1147; Miyasaka et al., Circulation, 2006, 114, 119-125. American Heart Association 2. HCUP ED & Admissions Data (2016), accessed

January 2021. 3. Rehorn et al. Journal of Cardiovascular Electrophysiology. 2021 Aug; 32(8): 2199-2206. doi: 10.1111/jce.15109. Epub 2021 Jun 14. 2018 prevalence of 2M anticipated to grow at a CAGR of ~2% 4. Quantitative Survey conducted by Triangle Insights, May 2021, N=250 Clinical Cardiologists, Interventional Cardiologists, and Electrophysiologists. 5. Estimate of TAM (~40%- 60% of prevalence) based on internal PSVT patient market research (BluePrint Research Group, n=247) and longitudinal analysis of claims data.

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CARDAMYST is a Novel L-type Investigational Calcium Channel Blocker Designed to Treat Episodes Quickly

Fast onset of action	Patient	Small enough to
(Tmax ≤ 7 min)	self-administered	fit in your pocket

Empowering patients to treat symptomatic attacks

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Current US PSVT Market

Total annual US healthcare expenditures of ~$3B

• Prevalence ~2M patients diagnosed with PSVT
• ~650K patients treated per year
• • ~300K newly diagnosed per year
  • >150K ED/hospital visits per year
  • ~80K ablations per year

Current Management

Ablations

12%

Pill-in-

No Treatment Pocket 34%

17%

Chronic Medications

Alone 37%

PSVT = Paroxysmal Supraventricular Tachycardia; ED = Emergency Department

Source: (1) Sacks, N.C. et al; Prevalence of Paroxysmal Supraventricular Tachycardia (PSVT) in the US in Patients Under 65 Years of Age; Abstract and Oral Presentation at the International Academy of Cardiology Annual Scientific Sessions 2018, 23rd World Congress on Heart Disease; Precision Xtract, Boston, MA, USA; and data-on-file from IBM Marketscan® Commercial Research Database (<65y) and the Medicare Limited Dataset (≥65y), with demographic, enrollment and claims data for commercially insured (Truven) and Medicare covered patients using PSVT code 427.0 or I47.1 for up to a 9-year interval between 2008 and 2016 inclusive; (2) Quantitative market research conducted by Triangle Insights Group (n=250 cardiologists), June-September 2020

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Core PSVT Market is Addressable Now*, with Large Potential for Expansion

Initial Target	Market

Future Target

Market

*if approved

~650k/year3

~1.4 Million2

~600-900k1

Diagnosed, Annually Treated Patients

Diagnosed, Not Annually Treated Patients

Undiagnosed Patients

2.1

Million

Sources: 1) assumes annual incidence rate for PSVT of ~300k from longitudinal claims analysis and the average time to diagnosis (currently 2-3 years) can be reduced to <6 months 2) Calculated as the difference between PSVT prevalence of 2.1M and annual treatment rate of ~650k from Truven MarketScan data, 2008-2016 analyzed by Precision Xtract, 2019 3) Estimated number of unique patients with annual claims for PSVT from Truven MarketScan data, 2008-2016 analyzed by Precision Xtract, 2019.

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CARDAMYST Has Substantial Potential Value for Stakeholder Groups If Approved

	Patients - Empowerment		Physicians -		Payers - More Efficient
		Dependable Tool		Use of Resources
•	Fast, reliable self-administration	•	Designed for patient self-	•	Novel and cost-effective
•	Less disruption, reliance on the	•	management	•	treatment
	Emergency Department	Frees up physician time	Reduction in ED/hospital
•	Less fear over when the next	•	and office resources		admissions
	event will occur	Trusted CCB mechanism

Sources: Internal market research, PSVT = Paroxysmal Supraventricular Tachycardia, CCB = Calcium Channel Blocker, ED = Emergency Department

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