Milestone Pharmaceuticals Reports Third Quarter 2022 Financial Results and Provides Clinical and Corporate Update - Phase 3 RAPID trial of etripamil in patients with PSVT achieved primary efficacy endpoint; safety and to

Milestone Pharmaceuticals

Reports Third Quarter 2022 Financial Results and Provides

Clinical and Corporate Update

Phase 3 RAPID trial of etripamil in patients with PSVT achieved primary efficacy

endpoint; safety and tolerability data from repeat

dose administration consistent with prior

studies utilizing single-dose administration of etripamil

- Analyses from etripamil Phase 3 PSVT studies featured during Late-Breaking session at

AHA Scientific Sessions 2022 demonstrated significant reductions in emergency

department utilization for etripamil-treated patients

Company plans to submit NDA for etripamil in PSVT to the U.S. FDA in mid-2023 pending

Montreal and Charlotte,

N.C., November 10, 2022 - Milestone Pharmaceuticals Inc. (Nasdaq: MIST), a biopharmaceutical company focused

on the development and commercialization of innovative cardiovascular medicines, today reported financial results for the third quarter

ended September 30, 2022, and provided a clinical and corporate update.

feedback we received from both clinicians and patient advocacy groups following the presentation of further RAPID data at the American

Heart Association (AHA) meeting earlier this week strengthen our conviction that etripamil has the potential to serve as a promising option

for patients with paroxysmal supraventricular tachycardia (PSVT)," said Joseph Oliveto, President and Chief Executive Officer of

Milestone Pharmaceuticals. "We are keenly focused on preparations for our planned New Drug Application (NDA), which we expect to

submit to the U.S. Food and Drug Administration (FDA) in mid-2023 pending agency feedback."

Supraventricular Tachycardia

Paroxysmal supraventricular

tachycardia (PSVT) is a condition affecting approximately two million Americans that is characterized by intermittent episodes of a rapid

heartbeat that starts and stops suddenly. Episodes of supraventricular tachycardia (SVT) are often associated with symptoms such as palpitations,

sweating, chest pressure or pain, shortness of breath, sudden onset of fatigue, lightheadedness or dizziness, fainting, and anxiety. Certain

intravenous medications, including adenosine, beta-blockers and calcium channel blockers, have long been used for the acute treatment

of PSVT. However, these medications must be administered under medical supervision, usually in an emergency department or other acute

About Atrial Fibrillation

with Rapid Ventricular Rate

(AFib) is a common arrhythmia marked by an irregular and often rapid heartbeat. AFib is estimated to affect five million patients in the

United States, a prevalence projected by the Centers for Disease Control to increase to twelve million patients within the next 10 years.

Atrial fibrillation with rapid ventricular rate (AFib-RVR) is a condition that some patients with AFib experience and includes episodes

of abnormally high heart rate, often with symptoms such as palpitations, shortness of breath, dizziness and weakness. Oral calcium channel

blockers and/or beta blockers are commonly used to reduce the heart rate in this condition. When AFib-RVR occurs, symptoms often cause

patients to seek acute care in the emergency department, where standard-of-care procedures include intravenous administration of calcium

channel blockers or beta blockers under medical supervision. Milestone's market research indicates that 30-40% of patients with AFib experience

one or more symptomatic episodes of RVR per year that require treatment, suggesting a target addressable market of approximately three

to four million patients in 2030 for etripamil in patients with AFib.

Etripamil, a new chemical entity, is Milestone's lead investigational

product. It is a novel calcium channel blocker designed to be a rapid-response therapy for episodic cardiovascular conditions. As a nasal

spray that is self-administered by the patient, etripamil has the potential to shift the current treatment experience for many patients

from the emergency department to a medically unsupervised setting. Milestone is conducting a comprehensive development program for etripamil,

with Phase 3 trials ongoing in paroxysmal supraventricular tachycardia (PSVT) and a Phase 2 proof-of-concept trial that is underway in

patients with atrial fibrillation with rapid ventricular rate (AFib-RVR).

Milestone Pharmaceuticals

Inc. (Nasdaq: MIST) is a biopharmaceutical company focused on the development and commercialization of innovative cardiovascular

medicines. Milestone's lead product candidate etripamil recently completed its Phase 3 clinical-stage program for the treatment of paroxysmal

supraventricular tachycardia (PSVT) and is in a Phase 2 proof-of-concept trial for the treatment of patients with atrial fibrillation

with rapid ventricular rate (AFib-RVR). Milestone Pharmaceuticals operates in Canada and the United States.

For more information, visit www.milestonepharma.com and follow Milestone on Twitter at @MilestonePharma.

This press release contains forward-looking statements

within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "believe," "continue," "could,"

"demonstrate," "designed," "develop," "estimate," "expect," "may,"

"pending," "plan," "potential," "progress," "will" and similar expressions (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 press release. 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 press release include statements regarding the potential of etripamil to serve as a promising

therapy for PSVT patients, the potential for clinical trial data from the phase 3 RAPID clinical trial of etripamil nasal spray in patients

with PSVT to support an NDA in mid-2023 pending agency feedback, the design, progress, timing, scope, recruitment and results of the RAPID

and ReVeRA trials; Milestone's ability to execute on the remainder of the PSVT program; the receipt of milestone payments from Ji

Xing, Milestone's ongoing plans to study etripamil in atrial fibrillation patients, the sufficiency of Milestone's current

cash resources to support its operations, and estimates about the addressable market and commercial potential for treatments of atrial

fibrillation with rapid ventricular rate. 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, evaluation

and results of our clinical trials; risks and uncertainty related to the complexity inherent in cleaning, verifying and analyzing trial

data; and whether the clinical trials will validate the safety and efficacy of etripamil for PSVT or other indications, among others,

general economic, political, and market conditions, including deteriorating market conditions due to investor concerns regarding inflation

and Russian hostilities in Ukraine and overall fluctuations in the financial markets in the United States and abroad, risks related to

pandemics and public health emergencies, including those related to the ongoing COVID-19 pandemic, and risks related the sufficiency of

Milestone's capital resources and its 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, 2021, under

the caption "Risk Factors," as such discussion may be updated from time to time by subsequent filings we may make with the U.S.

Securities & Exchange Commission. 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.

CONSOLIDATED STATEMENTS OF LOSS

(Unaudited, in thousands of US dollars, except share and per share data)

CONSOLIDATED BALANCE SHEETS

(Unaudited, in thousands of US dollars, except share data)