Milestone Pharmaceuticals : Corporate Presentation

Corporate Overview

September 2021

Joseph Oliveto

President & CEO

Disclaimers

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 possibility that data will support FDA approval, (iii) the potential market size and the rate and degree of market acceptance of 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, and (iv) the sufficiency of Milestone's capital resources. 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 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 etripamil for PSVT, 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, 2020, under the caption "Risk Factors." 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.

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Milestone (Nasdaq: MIST) - Corporate Highlights

Phase 3 Cardiovascular Company

Targeting Large	Paradigm-Changing	Recent Events Position
Areas of Unmet Need	Approach	for Future Success
PSVT	Etripamil - novel calcium	First Phase 3 study findings
	channel blocker	and FDA guidance in PSVT
	(IP protection until 2036)
AFib-RVR		Next Pivotal Phase 3 efficacy
		result in PSVT expected
	Shift from the ED to patient	by 2H 2022
Additional pipeline	self-management
opportunities		Financial runway expected
		through mid-2023

PSVT = Paroxysmal Supraventricular Tachycardia; AFib-RVR = Atrial Fibrillation with Rapid Ventricular Rate; ED = Emergency Department

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PSVT & AFib-RVR Populations in the US

		PSVT	Atrial Fibrillation
Total Patients (2016)	2	Million4	5 Million1
			(expected to grow to 7-12M by 20301,3)
Discharged ED Visits
& Hospital	145 Thousand	785 Thousand
Admissions (2016)2
Target Market
Addressable	0.8 -	1.2 Million6	2 Million5
(Patient Population)

Source(s): 1. Khavjou, et al., Projections of Cardiovascular Disease Prevalence and Costs: 2015-2035, American Heart Association, November 2016. 2. HCUP ED & Admissions Data (2016), accessed January 2021. 3. Colilla S, et al., Am J Card. 2013 112:1142-1147. 4. Sacks, N.C., et al., 23rd World Congress on Heart Disease (Boston 2018). 5. 40% of AF patients have >1 symptomatic episode per year of AF with RVR requiring treatment, Triangle Insights Group Market Research, N=25, January 2021. 6. 40-65% of PSVT patients have >1 episodes of PSVT requiring an ED visit, or having episodes lasting >10 minutes, or are on chronic prophylaxis for PSVT. Estimates based on internal market research and longitudinal analysis of claims data.

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Atrial Arrhythmias with a Common Patient Burden

Patients with PSVT and AFib-RVR report feeling a loss of control

PSVT		AFib-RVR
(AVNRT and AVRT)	(a subset of AFib)
Regular rapid heart rate	Irregular rapid heart rate
150 - 250 bpm	110 - 175 bpm
Episode frequency and duration is highly variable
Common		Heart palpitations / Chest pressure or pain
Symptoms		Shortness of breath / Fatigue
Include		Light-headedness / Anxiety

PSVT = Paroxysmal Supraventricular Tachycardia; AFib-RVR = Atrial Fibrillation with Rapid Ventricular Rate

Sources: adapted fromhttps://en.ecgpedia.org/index.php?title=Supraventricular_Rhythms, accessed 2/2021

Atrial Fibrillation

(multiple atrial

wavelets)

SA Node

AV Node

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

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