Form 8-K

8-K — Definium Therapeutics, Inc.

Accession: 0001104659-26-076091

Filed: 2026-06-22

Period: 2026-06-22

CIK: 0001813814

SIC: 2833 (MEDICINAL CHEMICALS & BOTANICAL PRODUCTS)

Item: Regulation FD Disclosure

Item: Other Events

Item: Financial Statements and Exhibits

Documents

8-K — tm2618434d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2618434d1_ex99-1.htm)

EX-99.2 — EXHIBIT 99.2 (tm2618434d1_ex99-2.htm)

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2026-06-22

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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 22, 2026

Definium Therapeutics, Inc.

(Exact name of Registrant as Specified in Its

Charter)

British Columbia

001-40360

98-1582438

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

One World Trade Center

Suite 8500

New York, New York

10007

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (212) 220-6633

(Former Name or Former Address, if Changed Since

Last Report)

Check the appropriate box below if the Form 8-K filing is intended

to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨Written

communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨Soliciting

material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨Pre-commencement

communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨Pre-commencement

communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of

the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange on which registered

Common Shares

DFTX

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth

company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities

Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company x

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Item 7.01 Regulation FD Disclosure.

On June 22, 2026, Definium Therapeutics, Inc. (the “Company”)

issued a press release (the “Press Release”) announcing positive topline data from the Company’s Phase 3 Emerge study

of DT120 ODT for the treatment of major depressive disorder. A copy of the Press Release is furnished as Exhibit 99.1 hereto, and

is incorporated by reference into this Item 7.01.

The information furnished pursuant to this Item 7.01, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of

1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be deemed to

be incorporated by reference into any of the Company’s filings with the SEC under the Exchange Act or the Securities Act of 1933,

as amended, whether made before or after the date hereof, regardless of any general incorporation language in such a filing, except as

expressly set forth by specific reference in such a filing.

Item 8.01 Other Events.

On June 22, 2026, the Company posted a presentation discussing

the Emerge topline data (the “Presentation”) on its website. A copy of the Presentation is filed as Exhibit 99.2 hereto,

and is incorporated by reference into this Item 8.01.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description

99.1

Press Release, dated June 22, 2026

99.2

Emerge Topline Data Presentation, dated June 22, 2026

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934,

the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

DEFINIUM THERAPEUTICS, INC.

Date:

June 22, 2026

By:

/s/ Robert Barrow

Name: Robert

Barrow

Title:   Chief Executive Officer

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2618434d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Definium Therapeutics Announces Positive Topline

Results from Phase 3 Emerge

Study of DT120 Orally Disintegrating Tablet (ODT) in Major Depressive Disorder

Study met primary

and all key secondary efficacy endpoints

8.1 point Montgomery-Åsberg Depression

Rating Scale (MADRS) placebo-adjusted change from baseline at Week 6 for the primary endpoint (p<0.0001)

7.3 point MADRS placebo-adjusted change from

baseline at Week 12, a secondary endpoint (p<0.0001)

DT120 ODT was generally well tolerated with

no serious adverse events or suicidality signal

Company to host webcast today at 8:00 a.m. EDT

NEW YORK

-- Definium Therapeutics, Inc. (“Definium” or the “Company”), a late-stage clinical biopharmaceutical

company developing a new generation of therapeutics intended to address underlying causes of psychiatric and neurological disorders,

today announced positive topline results from Emerge, its first randomized, double-blind, placebo-controlled Phase 3 study evaluating

a single dose of DT120 (lysergide) ODT 100 µg in adults with major depressive disorder (MDD).

Emerge met its primary endpoint, demonstrating a statistically significant

and clinically meaningful improvement from baseline compared with placebo, as measured by the change in MADRS total score at week 6.

The Least Squares (LS) mean change from baseline in MADRS total score at Week 6 in participants who received DT120 ODT 100 µg was

-13.3 compared with -5.2 for patients who received placebo, a LS mean difference of -8.1 points (p<0.0001). Beyond the primary endpoint,

the effect was rapid with a placebo-adjusted LS mean reduction in MADRS total score at Week 1 of -14.2 (p<0.0001) and durable with

a placebo-adjusted LS mean reduction in MADRS total score of -7.3 at Week 12 (p<0.0001).

“The Emerge topline results represent unprecedented and highly

differentiated efficacy, demonstrating that a single dose of DT120 ODT can deliver rapid, robust, and durable relief in MDD,” said

Rob Barrow, Chief Executive Officer of Definium Therapeutics. “As the first of our Phase 3 studies to report results, Emerge marks

a major milestone in our development program and strengthens our confidence in DT120 as a potential best-in-class treatment for mental

health disorders. These findings could support a fundamentally new approach to treating MDD for patients and providers who continue to

face the limitations of existing treatment options. We are deeply grateful to the patients and investigators who participated in this

trial. Grounded in decades of scientific research, these results bring us one step closer to potentially delivering a transformative

new treatment option as we advance toward FDA submission.”

DT120 ODT

was generally well tolerated with 99% of treatment-emergent adverse events mild to moderate in severity, transient, and predominantly

occurring on the day of dosing. No new safety signals were identified, including no increase in suicidal ideation or behavior,

and discontinuation rates were low and comparable between treatment groups. On the day of dosing, participants were assessed hourly from

hours 5 to 8 on a structured end of session checklist (EoSC). The average time to meeting EoSC criteria was 5.8 hours for participants

receiving DT120 ODT in Part A, with a median of 5.1 hours and 100% of participants meeting the EoSC criteria by hour 8.

“Many

patients with MDD aren’t helped by existing treatments, often experiencing partial responses, frequent medication changes, and

long-term side effects,” said John Sonnenberg, Ph.D., Emerge principal investigator, clinical psychologist, founder of Uptown Research

Institute, and faculty member at Northwestern University Feinberg School of Medicine. “The Emerge topline results demonstrate

that a single dose of DT120 ODT can produce a meaningful and durable benefit for people with depression. Importantly,

these results stand apart from existing treatments, representing a potentially new paradigm for the management of major depression.”

Highlights from Emerge Topline Results

The mean baseline MADRS score at study entry was 35.0 in the DT120

ODT treatment group (n=75) and 34.0 in the placebo ODT group (n=74).

Endpoint

DT120

ODT

100 µg

Placebo

ODT

Placebo-Adjusted

Difference

MADRS:

LS mean change at Week 6*

-13.3

-5.2

-8.1

(p<0.0001)

MADRS:

LS mean change at Week 12**

-11.0

-3.6

-7.3

(p<0.0001)

MADRS:

LS mean change at Week 1**

-17.6

-3.4

-14.2

(p<0.0001)

CGI-S:

LS mean change at Week 6**

-1.2

-0.3

-0.9

(p<0.0001)

CGI-S:

LS mean change at Week 12**

-1.0

-0.3

-0.7

(p<0.0001)

CGI-S:

LS mean change at Day 2**

-1.0

-0.1

-0.9

(p<0.0001)

MADRS:

response rate (≥50%) at Week 6***

35%

28%

(p<0.001)

MADRS:

remission rate (≤12) at Week 6***

24%

21%

(p<0.01)

*Pre-specified primary endpoint

**Pre-specified key secondary endpoint

*** Pre-specified secondary endpoint

CGI-S = Clinical Global Impressions – Severity Scale; LS = least

squares; LS mean difference = difference in LS means of change from baseline between DT120 and placebo groups

Webcast Details

Definium

Therapeutics management will host a webcast at 8:00 a.m. EDT today to review the Phase 3 Emerge study topline results. Listeners

can register for the webcast via this link. Analysts wishing to participate in the question-and-answer

session should use this link. A replay of the webcast will be available via the Investor Relations section of the Definium Therapeutics

website, ir.definiumtx.com, and archived for at least 30 days after the webcast. Those who plan on participating are advised to join

15 minutes prior to the start time.

About Emerge

Emerge

is a Phase 3, multicenter, randomized, double-blind, placebo-controlled study evaluating the efficacy and safety of a single 100 µg

dose of DT120 ODT versus placebo in participants with major depressive disorder (MDD).

♦      2

The study consists of a 12-week

double-blind phase (Part A) followed by a 40-week open-label extension phase (Part B) during which participants may be eligible

to receive DT120 ODT based on symptom severity. The study enrolled 149 participants

aged 18 to 74 years across 20 sites with a DSM-5-confirmed diagnosis of MDD, a Montgomery-Åsberg Depression Rating Scale

(MADRS) total score of at least 26, and a Clinical Global Impression–Severity (CGI-S) score of at least 4 at screening and baseline.

The primary endpoint is change

from baseline in the MADRS total score at Week 6. Key secondary endpoints are change from baseline in CGI-S score at Week 6, Week 12

and Day 2 and change from baseline in MADRS total score at Week 12 and Week 1.

Emerge

is one of two pivotal Phase 3 studies in MDD. Ascend, the second Phase 3 study in MDD, is aligned with Emerge, but

includes a low dose arm and is also conducted in two parts: Part A, a 12-week, randomized, double-blind, placebo-controlled, parallel-group

period; and Part B, a 40-week extension period during which participants will be eligible for open-label treatment with DT120 ODT

based on symptom severity. Participants will be randomized 2:1:2 to receive DT120 ODT 100 µg, DT120 ODT 50 µg, or placebo.

The 50 µg arm is intended to confound participants’ ability to accurately assess the dose condition to which they

have been randomized. This approach continues to build on the Company’s Phase 2b study of DT120 in generalized anxiety disorder

(GAD), which the Company believes demonstrated that DT120’s clinical activity is not attributable to functional unblinding and

aligns with FDA guidance on the use of complementary designs across the Company’s DT120 clinical development program. The primary

endpoint of Ascend is change from baseline in MADRS total score at Week 6 between DT120 ODT 100 µg and placebo.

About Major Depressive Disorder

(MDD)

Major Depressive Disorder (MDD)

is the second-most common mental health disorder in the U.S., with over 21 million adults experiencing a major depressive episode (MDE)

each year.1,2 This disorder, a leading cause of disability worldwide,3 brings persistent feelings of worthlessness,

fatigue, and recurrent thoughts of death4 while increasing long-term mortality risk by 40%.5 MDD also carries a

$326 billion annual economic burden in the U.S., driven by healthcare costs and lost productivity.6 The MDD treatment paradigm

is characterized by critical unmet needs, including fewer than one-third of patients reaching remission with first-line treatments,7

onset of clinical activity that takes weeks to months,8,9 poor tolerability,10,11 and frequent switching,

augmentation, and discontinuation of pharmacotherapy.12

About

DT120 (lysergide) Orally Disintegrating Tablet (ODT)

DT120 ODT is an ergoline derivative belonging to the group of classic

serotonergic psychedelics, which acts as a partial agonist at serotonin-2A (5-HT2A) receptors. DT120 ODT is Definium’s proprietary

and pharmaceutically optimized formulation of LSD. DT120 ODT is an advanced formulation incorporating Catalent’s Zydis® ODT

fast-dissolve technology, designed to deliver several unique advantages, including faster absorption and onset of transient cognitive,

perceptual, and affective changes, improved bioavailability, and a lower incidence of gastrointestinal side effects. Definium is developing

DT120 ODT, the tartrate salt form of lysergide, for generalized anxiety disorder (GAD), major depressive disorder (MDD), posttraumatic

stress disorder (PTSD), and is exploring its potential applications in other serious brain health disorders. DT120 has received Breakthrough

Therapy designation from the FDA for GAD. Definium maintains a strong foundation to protect and extend the long-term value of the DT120

ODT franchise through a multi-layered intellectual property strategy spanning composition, formulation, and methods-of-use patents.

♦      3

About Lysergide (LSD)

Lysergide (LSD) is one of the most extensively studied psychopharmaceuticals

in history, with over 1,000 published reports.13 First synthesized in 1938 by Swiss chemist Albert Hofmann in his search for

active principles from ergot fungus, its profound psychological effects were discovered in 1943, which transformed psychiatric research.13

LSD, a definitional classic psychedelic, temporarily alters perception, cognition, and emotion, is physiologically safe, non-addictive,

and isn’t associated with withdrawal.13 While its precise mechanism of action in the treatment of psychiatric illness

is unknown, its acute perceptual, cognitive, and affective effects are mediated by agonism of the serotonin 5-hydroxytryptamine 2A (5-HT2A)

receptor, and mechanistic hypotheses suggest that it causes sustained increases in neuroplasticity in a variety of brain regions.14,15

About Definium Therapeutics

The mission of Definium Therapeutics is to forge a new era of psychiatry

by applying scientific rigor to psychedelics, with the goal of developing accessible treatments that unlock healing at scale. Guided

by a recognition that patients deserve more than better, Definium is relentlessly advancing a new generation of therapeutics intended

to address underlying causes of psychiatric and neurological disorders. By turning evidence into impact, Definium aims to change the

trajectory of today’s mental health care crisis and enable a healthier future. Headquartered in New York, Definium Therapeutics

trades on Nasdaq under the symbol DFTX.

♦      4

Forward-Looking Statements

Certain statements

in this news release related to the Company constitute “forward-looking information” within the meaning of applicable securities

laws and are prospective in nature. Forward-looking information is not based on historical facts, but rather on current expectations

and projections about future events and are therefore subject to risks and uncertainties which could cause actual results to differ materially

from the future results expressed or implied by the forward-looking statements. These statements generally can be identified by the use

of forward-looking words such as “will”, “may”, “should”, “could”, “intend”,

“estimate”, “plan”, “anticipate”, “expect”, “believe”, “potential”

or “continue”, or the negative thereof or similar variations. Forward-looking information in this news release includes,

but is not limited to, statements regarding the anticipated design, timing, progress and results of the Company’s investigational

programs for DT120 ODT for the treatment of generalized anxiety disorder, major depressive disorder and posttraumatic stress disorder

(including the anticipated topline readouts for the Voyage, Panorama, and Ascend studies), the success and timing of the Company’s

development activities; the likelihood of success of any clinical trials or of obtaining U.S. Food and Drug Administration (“FDA”)

or other regulatory approvals; the Company’s beliefs regarding potential benefits of its product candidates; the Company’s

belief that DT 120 ODT can deliver rapid, robust, and durable relief for people living with MDD; the Company’s belief that DT120

ODT could be a best-in-class treatment for mental health disorders; the Company’s belief that the results from its Phase 3 Emerge

Study of DT120 ODT could support a fundamentally new approach to treating MDD and a transformative new treatment option; the ability

of DT120 ODT to be a potentially new paradigm for the management of major depression; and the potential for psychedelics as a class of

treatment options in psychiatry. There are numerous risks and uncertainties that could cause actual results and the Company’s plans

and objectives to differ materially from those expressed in the forward-looking information, including history of negative cash flows;

limited operating history; incurrence of future losses; availability of additional capital; compliance with laws and regulations; legislative

and regulatory developments, including decisions by the Drug Enforcement Administration and states to reschedule any of the Company’s

product candidates, if approved, containing Schedule I controlled substances, before they may be legally marketed in the U.S.; difficulty

associated with research and development; risks associated with clinical studies or studies; heightened regulatory scrutiny; early stage

product development; clinical study risks; regulatory approval processes; novelty of the psychedelic inspired medicines industry; ability

to maintain effective patent rights and other intellectual property protection for the Company’s product candidates, the Company’s

expectations regarding the size of the eligible patient populations for its lead product candidates, if approved and commercialized;

the Company’s ability to identify third-party treatment sites to conduct its trials and its ability to identify and train appropriate

qualified healthcare practitioners to administer its treatments; the pricing, coverage and reimbursement of the Company’s lead

product candidates, if approved and commercialized; the rate and degree of market acceptance and clinical utility of the Company’s

lead product candidates, in particular, and controlled substances, in general as well as those risk factors discussed or referred to

herein and the risks, uncertainties and other factors described in the Company’s Annual Report on Form 10-K for the fiscal

year ended December 31, 2025 and its Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2026, under

headings such as “Special Note Regarding Forward-Looking Statements,” and “Risk Factors” and “Management’s

Discussion and Analysis of Financial Condition and Results of Operations” and other filings and furnishings made by the Company

with the securities regulatory authorities in all provinces and territories of Canada which are available under the Company’s profile

on SEDAR+ at www.sedarplus.ca and with the U.S. Securities and Exchange Commission on EDGAR at www.sec.gov. Except as required by law,

the Company undertakes no duty or obligation to update any forward-looking statements contained in this release as a result of new information,

future events, changes in expectations or otherwise.

References:

1. National Institute of Mental Health (NIMH). “Major Depression: Prevalence

of Major Depressive Episode Among Adults.” Updated 2024.

2. Substance Abuse and Mental Health Services Administration (SAMHSA). “2023

National Survey on Drug Use and Health (NSDUH).”

3. World Health Organization (WHO). “Depression Fact Sheet.”

Updated 2023.

4. American Psychiatric Association. “Diagnostic and Statistical Manual

of Mental Disorders, 5th Edition (DSM-5).” 2013.

5. Cuijpers, P., et al. “Long-Term Mortality Risk in Depression: A

20-Year Follow-Up Study.” JAMA Psychiatry, 2023.

6. Greenberg, P. E., et al. “The Economic Burden of Adults with Major

Depressive Disorder in the United States (2020).” Journal of Clinical Psychiatry, 2024.

7. Rush, A. J., et al. “Acute and Longer-Term Outcomes in Depressed

Outpatients Requiring One or Several Treatment Steps: A STAR*D Report.” American Journal

of Psychiatry, 2006.

8. APA. Practice Guideline for the Treatment of Patients with Major Depressive

Disorder. Published 2010.

♦      5

9. Alemi F, Min H, et al. Effectiveness of common antidepressants: A post

market release study. eClinicalMedicine. 2021;41.

10. Cipriani A, et al. Comparative Efficacy and acceptability of 21 antidepressant

drugs for the Acute Treatment of Adults with Major Depressive Disorder: A Systematic Review

and Network Meta-analysis. Lancet. 2018;391(10128):1357-66.

11. Braund TA, Tillman G, et al. Antidepressant Side Effects and Their Impact

on Treatment Outcome in People with Major Depressive Disorder: An Ispot-D Report. Transl

Psychiatry. 2021;11(1):417.

12. Zhu L, Ferries E, et al. Economic Burden and Antidepressant Treatment

Patterns Among Patients with Major Depressive Disorder in the United States. J Manag Care

Spec Pharm. 2022 Nov;28(11-a Suppl): S2-S13.

13. Nichols, DE. “Psychedelics.” Pharmacological Reviews, 2016;68(2):

264–355.

14. Passie, T, Halpern, JH, Stichtenoth, DO, et al. “The Pharmacology

of Lysergic Acid Diethylamide: A Review.” CNS Neuroscience & Therapeutics.

2008;14:295–314.

15. Liechti, ME. “Modern clinical research on LSD.” Neuropsychopharmacology.

2017;42: 2114–2127.

Investors:

Gitanjali

Jain

VP, Head of Investor Relations

ir@definiumtx.com

Media:

media@definiumtx.com

♦      6

EX-99.2 — EXHIBIT 99.2

EX-99.2

Filename: tm2618434d1_ex99-2.htm · Sequence: 3

Exhibit 99.2

Phase 3 Emerge Study Topline Data Readout

This presentation (the “Presentation”) has been prepared by Definium Therapeutics, Inc. (“Definium”, the “Company”, “we”, “ou r” or “us") solely for informational purposes. This Presentation does not constitute an offering of, or a solicitation of an off er to purchase, securities of Definium and under no circumstances is it to be construed as a prospectus or advertisement or public offering of securitie s. Any trademarks included herein are the property of the owners thereof and are used for reference purposes only. Such use shou ld not be construed as an endorsement of the products or services of Definium. Any amounts are in USD unless otherwise noted. Definium’s securities hav e not been approved or disapproved by the U.S. Securities and Exchange Commission (the "SEC") or by any state, provincial or oth er securities regulatory authority, nor has the SEC or any state, provincial or other securities regulatory authority passed on the accurac y o r adequacy of this Presentation. Any representation to the contrary is a criminal offense. Cautionary Note Regarding Forward - Looking Statements This Presentation contains, and our officers and representatives may from time to time make, “forward - looking statements” within the meaning of applicable securities laws and are prospective in nature. Forward - looking statements are not based on historical facts, but rather on current expectations and projections about future events and are therefore subject to risks and uncertainties which could cau se actual results to differ materially from the future results expressed or implied by the forward - looking statements. These sta tements generally can be identified by the use of forward - looking words such as “will”, “may", “should”, “could”, “intend”, “estimate”, “plan”, “antic ipate”, “expect”, “believe”, “potential”, “continue”, “budget”, “scheduled”, “forecasts”, “intends”, “anticipates”, “projects ” o r the negative thereof or similar variations. Forward - looking statements in this Presentation include, but are not limited to, statements regarding the an ticipated design, timing, progress and results of our investigational programs for DT120 oral disintegrating tablet (“ODT”), a p roprietary, pharmaceutically optimized form of lysergide tartrate for the treatment of generalized anxiety disorder, major depressive dis ord er and posttraumatic stress disorder (including the anticipated topline readouts for the Voyage, Panorama and Ascend studies) , D T402, also referred to as R( - ) - MDMA, and any other product candidates; potential expansion of our current pipeline; the success and timing of our de velopment activities; our ability to meet the milestones set forth herein; the likelihood of success of any clinical trials o r o f obtaining U.S. Food and Drug Administration (“FDA”) or other regulatory approvals; our beliefs regarding potential benefits of our product candidates ; o ur belief that DT120 ODT represents a best - in - class profile; the potential commercial opportunity for DT120 ODT, if approved, i ncluding total addressable market; our plans to continue to advance commercial readiness activities, including market access and provider ed uca tion; our cash position; and the potential for psychedelics as a class of treatment options in psychiatry. There are numerous risks and uncertainties that could cause actual results, plans and objectives to differ materially from th ose expressed in forward - looking statements, including history of negative cash flows, limited operating history, incurrence of fut ure losses, availability of additional capital, compliance with laws and regulations, difficulty associated with research and development, risks associat ed with clinical trials or studies, heightened regulatory scrutiny, early stage product development, clinical trial risks, regul ato ry approval processes, novelty of the psychedelic inspired medicines industry, our ability to maintain effective patent rights and other intellectua l p roperty protection for our product candidates, our expectations regarding the size of the eligible patient populations for ou r l ead product candidates, if approved and commercialized; our ability to identify third - party treatment sites to conduct our trials and our ability to identi fy and train appropriate qualified healthcare practitioners to administer our treatments; the pricing, coverage and reimburse men t of our lead product candidates, if approved and commercialized; the rate and degree of market acceptance and clinical utility of our lead product ca ndidates, in particular, and controlled substances, in general; as well as those risk factors described in the Company's Annu al Report on Form 10 - K for the fiscal year ended December 31, 2025, and the Company’s Quarterly Report on Form 10 - Q for the quarterly period ended March 31 , 2026, under headings such as “Special Note Regarding Forward - Looking Statements,” and “Risk Factors” and “Management's Discuss ion and Analysis of Financial Condition and Results of Operations” and other filings and furnishings made by the Company with the sec uri ties regulatory authorities in all provinces and territories of Canada which are available under the Company's profile on SED AR+ at www.sedarplus.ca and with the SEC on EDGAR at www.sec.gov. Any forward - looking statement made by Definium in this Presentation is based only on information currently available to the Comp any and speaks only as of the date on which it is made. Except as required by law, the Company undertakes no duty or obligati on to update any forward - looking statements contained in this Presentation as a result of new information, future events, changes in expectations or otherwise. Cautionary Note Regarding Regulatory Matters The United States federal government regulates drugs through the Controlled Substances Act. DT120 ODT is a proprietary, pharm ace utically optimized form of lysergide D - tartrate and DT402, or R( - ) - MDMA, is our proprietary form of the R - enantiomer of MDMA (3, 4 - methylenedioxymethamphetamine). Lysergide and MDMA are Schedule I substances under the Controlled Substances Act. While the C omp any is focused on programs using psychedelic or hallucinogenic compounds and non - hallucinogenic derivatives of these compounds, including in DT120 ODT, DT402 and its other product candidates, the Company does not have any direct or indirect involvement wit h the illegal selling, production or distribution of any substances in the jurisdictions in which it operates. The Company is a neuro - pharmaceutical drug development company and does not deal with psychedelic or hallucinogenic substances except within laboratory and clinica l t rial settings conducted within approved regulatory frameworks. The Company's products will not be commercialized prior to app lic able regulatory approval, which will only be granted if clinical evidence of safety and efficacy for the intended uses is successfully develo ped . Market and Industry Data This Presentation includes market and industry data that has been obtained from third party sources, including industry publi cat ions. Definium believes that the industry data is accurate and that the estimates and assumptions are reasonable, but there i s n o assurance as to the accuracy or completeness of this data. Third party sources generally state that the information contained therein has been ob tai ned from sources believed to be reliable, but there is no assurance as to the accuracy or completeness of included informatio n. Although the data is believed to be reliable, Definium has not independently verified any of the data from third party sources referred to in this Pr esentation or ascertained the underlying economic assumptions relied upon by such sources. References in this Presentation to re search reports or to articles and publications should not be construed as depicting the complete findings of the entire referenced report or artic le. Definium does not make any representation as to the accuracy of such information. Emerge Topline Results | June 2026 2 Disclaimer

Opening Remarks Rob Barrow Chief Executive Officer

Thank you to our study participants, investigators and partners who made Emerge possible

5 1. Single dose regimen is being studied in pivotal clinical trials with primary and secondary outcome measures through 12 weeks aft er administration. Phase 3 studies include 40 week extension phase to characterize durability of response beyond 12 weeks in participants up until the time of discontinuation or the administration of open - label DT120. 2. Required monitoring period for all participants in pivotal studies is 8 hours and requires that participants clear the End of Se ssion Checklist. 3. Ringeisen, H., et al. (2023). Mental and Substance Use Disorders Prevalence Study (MDPS): Findings Report, Zhou, Y,. Et al. (20 17). Nature. Comorbid generalized anxiety disorder and its association with quality of life in patients with major depressive disorder. RTI International and current U.S. Census data and internal company estimates. GAD: generalized anxiety disorder; MDD: major depressive disorder Target Product Profile to Address Significant Unmet Need Emerge Topline Results | June 2026 1 Dose 1 Weeks of Durability 1 Hours in the Clinic 2 US Adults with GAD & MDD 3 5 - 8 12+ 50M

Emerge Topline Results | June 2026 6 First Pivotal Readout for DT120 ODT 1. Clinical study designs subject to change based on ongoing regulatory discussion and review, including of Phase 3 clinical tri al protocols 2. Includes the primary endpoint and all hierarchically controlled key secondary endpoints. DB: double blind; HAM - A: Hamilton Anxiety Rating Scale; MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegra ting tablet; OL: open - label; RCT: randomized controlled trial; Δ : placebo - adjusted delta Generalized Anxiety Disorder (GAD) Major Depressive Disorder (MDD) n=214 1 :1 randomization Enrollment Complete DT120 ODT vs. Placebo ▪ Part A: 12 - week DB, RCT ▪ Part B: 40 - week Extension with OL Treatment n=245 2:1:2 randomization Enrollment Complete DT120 ODT vs. Placebo including 50 µg control ▪ Part A: 12 - week DB, RCT ▪ Part B: 40 - week Extension with OL Treatment n=149 1:1 randomization Enrollment Complete DT120 ODT vs. Placebo ▪ Part A: 12 - week DB, RCT ▪ Part B: 40 - week Extension with OL Treatment Target n=165 1 2:1:2 randomization DT120 ODT vs. Placebo including 50 µg control ▪ Part A: 12 - week DB, RCT ▪ Part B: 40 - week Extension with OL Treatment Target n=200 1 1:1 randomization DT120 ODT vs. Placebo ▪ Part A: 12 - week DB, RCT ▪ Part B: 40 - week Extension with OL Treatment Posttraumatic Stress Disorder (PTSD) Anticipated Topline Readout Early 3Q 2026 Anticipated Topline Readout Late 3Q 2026 Met All Primary & Key Secondaries 2 Enrolling Planning

Emerge Topline Results | June 2026 7 Emerge Results Demonstrate Potential Best - in - Class Efficacy in Major Depressive Disorder Limited side effect burden Efficient session dynamics Rapid, robust and durable efficacy after single dose ▪ All primary and key secondary endpoints highly statistically significant ▪ 8.1 point MADRS improvement over placebo at week 6 primary endpoint (p<0.0001) ▪ 7.3 point MADRS improvement over placebo at week 12 (p<0.0001) ▪ 0.9 point CGI - S improvement over placebo at day 2 (p<0.0001) ▪ DT120 ODT generally well tolerated ▪ No SAEs or suicidality signal ▪ 5.8 hour average time to clear End of Session Checklist (EoSC) ▪ All participants cleared EoSC by 8 hours CGI - S: Clinical Global Impression - Severity Scale; MADRS: Montgomery - Åsberg Depression Rating Scale; MDD: major depressive disor der; ODT: orally disintegrating tablet; SAEs: serious adverse events

Emerge Topline Results | June 2026 Putting the Numbers in Perspective 1 8 GAD Placebo adjusted changes in HAM - A MDD Placebo adjusted changes in MADRS 1. The information presented in this slide on comparative treatments is derived from multiple clinical trials, each conducted un der distinct protocols and settings. As such, these data may not be directly comparable due to the lack of a head - to - head compariso n. Differences in trial design, patient demographics, and other variables may account for variations in the observed outcomes. S tud y results for each drug are intended to be representative, however, multiple trials of the approved treatments. 2. Median placebo - adjusted change of comparative treatments for GAD. See references on slide 19 of Investor and Analyst Day Present ation filed on Form 8 - K, Exhibit 99.2 on April 22, 2026 with the SEC. 3. Median placebo - adjusted change of comparative treatments for depression symptoms. See references on slide 20 of Investor and Analyst Day Presentation filed on Form 8 - K, Exhibit 99.2 on April 22, 2026 with the S EC. 4. R Robison, JAMA. 2025 Sep 4; e2513481. doi:10.1001/jama.2025.13481. 5. MADRS change from Baseline to week 12 was a secondary endpoint in Study MMED008. 5.0 3.2 3 7.7 3.9 4 Latest Generation of Comparative Treatments Phase 3 Powering Assumption 2 DT120 Results 8.1 point placebo - adjusted difference in MDD with extended durability and favorable tolerability represents a potential best - in - class profile Improvement 8.1 | Week 6 Phase 2b | Week 12 5

Phase 3 Emerge Study Results Part A – Topline Results Dan Karlin, MD Chief Medical Officer

Emerge Trial Design MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegrating tablet; PHQ - 9: a multipurpose instrument for screen ing, diagnosing, monitoring and measuring the severity of depression; µg: microgram DT120 ODT 1 00 µg n=75 Placebo n=74 Part A 12 Week Randomized, Double - Blind Part B 40 Week Extension with Opportunity for Open - Label Treatment PHASE 3 STUDY 1 Single Dose Primary Endpoint MADRS at Week 6 Up to four open - label doses of DT120 ODT 1 00 µg Follow - up Observation PHQ - 9 (ePRO): biweekly MADRS (central rater): monthly or when PHQ - 9 ≥ 10 Potential Treatment Eligible for open - label treatment if MADRS ≥ 20 10 Emerge Topline Results | June 2026

11 ITT: intent to treat; ODT: orally disintegrating tablet Participant Disposition Emerge Topline Results | June 2026 Randomized n=149 DT120 ODT n=75 Placebo ODT n=74 ▪ 100% included in ITT population ▪ 85% completed Part A ▪ 100% included in ITT population ▪ 82% completed Part A

12 1. Based on ITT population. 2. Mean (SD). 3. The MADRS is a 10 - item clinician - rated outcome measure assessing various domains of depression with a range of 0 - 60. In Emerge, MADRS ratings were assessed by central raters blinded to both treatment assignment and visit number. 4. The CGI - S is a clinician - rated outcome measure assessing overall severity of illness with a range of 1 to 7. 5. Psychedelics include LSD, psilocybin, dimethyltryptamine and other classic serotonergic psychedelics. CGI - S: Clinical Global Impressions – Severity Scale; ITT: intent to treat; LSD: lysergic acid diethylamide; MADRS: Montgomery - Å sberg Depression Rating Scale; ODT: orally disintegrating tablet Demographics & Baseline Characteristics 1 Overall n=149 Placebo ODT n=74 DT120 ODT n=75 Demographic 43.6 42.2 44.9 Mean age (years) 46% 42% 49% Sex (% female) 66% 69% 64% Race (% white) 34.5 (4.4) 34.0 (3.7) 35.0 (5.0) Baseline MADRS score 2,3 4.8 (0.6) 4.8 (0.6) 4.7 (0.6) Baseline CGI - S score 2,4 Past Psychedelic Use, n (%) 23 (15%) 10 (14%) 13 (17%) Any psychedelic 5 6 (4%) 3 (4%) 3 (4%) LSD Emerge Topline Results | June 2026

13 1. Based on ITT population ITT: intent to treat; MADRS: Montgomery - Åsberg Depression Rating Scale; MDD: major depressive disorder; ODT: orally disintegrati ng tablet; SD: standard deviation Baseline Characteristics | Representative of MDD Patients with High Burden of Disease 1 Emerge Topline Results | June 2026 Overall n=149 Placebo ODT n=74 DT120 ODT n=75 Diagnostic Trait 34.5 (4.4) 34.0 (3.7) 35.0 (5.0) MADRS score, n (SD) MADRS severity, n (%) 25 (17%) 10 (14%) 15 (20%) Moderate (20 - 30) 124 (83%) 64 (87%) 60 (80%) Severe (≥31) Number of past antidepressants, n (%) 41 (28%) 23 (31%) 18 (24%) 0 29 (20%) 13 (18%) 16 (21%) 1 79 (53%) 38 (51%) 41 (55%) 2+

14 1. Based on ITT population ITT: intent to treat; ODT: orally disintegrating tablet; SD: standard deviation Baseline Characteristics | Course of Illness Consistent with Representative and High Burden Population 1 Emerge Topline Results | June 2026 Overall N=149 Placebo ODT n=74 DT120 ODT n=75 Diagnostic Trait Length of current depressive episodes 8.9 (5.4) 8.9 (5.8) 8.8 (5.0) Mean months (SD) 112 (75%) 52 (70%) 60 (80%) < 1 year 37 (25%) 22 (30%) 15 (20%) 1 - 2 years 0 0 0 > 2 years Number of lifetime depressive episodes 5.8 (4.6) 6.2 (5.4) 5.5 (3.5) Mean (SD) 49 (33%) 25 (34%) 24 (32%) 1 - 2 47 (32%) 21 (28%) 26 (35%) 3 - 4 53 (36%) 28 (38%) 25 (33%) ≥ 5

Primary Endpoint: MADRS Change from Baseline to Week 6 15 1. Source: Emerge study documents. ITT population. 2. Primary endpoint of the study was change in MADRS at week 6 using a Mixed - Effects Model Repeated Measures (MMRM) statistical ana lysis with reference - based imputation. LS Mean: least squares mean; MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegrating tablet; SEM: standard error of the mean DT120 ODT Showed Statistically & Clinically Significant Improvements on MADRS at All Timepoints 1,2 Emerge Topline Results | June 2026 -20 -15 -10 -5 0 LS Mean Change (SEM) in MADRS score **** **** **** **** **** Week 1 Week 2 Week 4 Week 6 Week 12 Change from Baseline 2 ▪ Week 1: - 17.6 points ▪ Week 4: - 13.6 points ▪ Week 6: - 13.3 points ▪ Week 12: - 11.0 points Improvement over Placebo 2 ▪ Week 1: - 14.2 points ▪ Week 4: - 9.8 points ▪ Week 6: - 8.1 points ▪ Week 12: - 7.3 points ****p<0.0001 Placebo ODT DT120 ODT Highlights

16 1. Source: Emerge study documents. ITT population. 2. Key secondary endpoint of the study was change in CGI - S at week 6 using a Mixed - Effects Model Repeated Measures (MMRM) statistic al analysis with reference - based imputation. CGI - S: Clinical Global Impressions – Severity scale; LS Mean: least squares mean; ODT: orally disintegrating tablet; SEM: standa rd error of the mean DT120 ODT Showed Statistically & Clinically Significant Improvements on CGI - S at All Timepoints 1,2 Emerge Topline Results | June 2026 Change from Baseline 2 ▪ Day 2: - 1.0 points ▪ Week 1: - 1.7 points ▪ Week 4: - 1.4 points ▪ Week 6: - 1.2 points ▪ Week 12: - 1.0 points Improvement over Placebo 2 ▪ Day 2: - 0.9 points ▪ Week 1: - 1.4 points ▪ Week 4: - 1.1 points ▪ Week 6: - 0.9 points ▪ Week 12: - 0.7 points -2 -1.5 -1 -0.5 0 LS Mean Change (SEM) in CGI - S score Placebo ODT DT120 ODT **** **** **** **** **** Week 1 Week 2 Week 4 Week 6 Week 12 **** Day 2 Key Secondary Endpoint: CGI - S Change from Baseline to Week 6 Highlights ****p<0.0001

17 DT120 ODT Effects Supported by Robust, Statistically Significant Response and Remission Rates 1 Emerge Topline Results | June 2026 24% 41% 3% 13% 0% 10% 20% 30% 40% 50% 60% Remission MADRS ≤ 12 Mild or better MADRS < 20 Remission Rate at Week 6 35% 60% 7% 27% 0% 10% 20% 30% 40% 50% 60% Response ≥ 50% Improvement Response ≥ 25% Improvement Response Rate at Week 6 1. Source: Emerge study documents. ITT population. Pre - planned secondary endpoint. 2. Remission rates using a cutoff of MADRS ≤10 was 24% for DT120 ODT compared to 3% for placebo ODT. ODT: orally disintegrating tablet ; MADRS: Montgomery - Åsberg Depression Rating Scale **p<0.01, ***p<0.001, ****p<0.0001 **** *** ** *** Placebo ODT DT120 ODT 2

18 1. Source: Emerge study documents. Subgroup analysis of ITT population. 2. Data presented as LSmean ± standard error. 3. For each subgroup, the change from baseline in MADRS total score is analyzed using the same MMRM model as the primary efficac y a nalysis. If the number of patients is small for a subgroup, the treatment difference will not be stable as it would be highly sensitive to outliers. Δ : change ; MADRS: Montgomery - Åsberg Depression Rating Scale Treatment Effect Maintained Across Key Subgroups – Including Those Failed by 2+ Prior Treatments 1 Emerge Topline Results | June 2026 Placebo Adjusted Δ Subgroup Analysis of MADRS Change at Week 6 2 0 - 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 All participants Time since diagnosis <12 yrs (n=67) > 12 yrs (n=82) Previous MDD Medications Less than two (n=70) Two or more (n=79) Sex Male (n=81) Female (n=68) Favors DT120

DT120 ODT was Generally Well - Tolerated and Consistent with Known Pharmacology 1 1. Source: Emerge study documents. Safety population in study part A (through week 12). 2. The one severe adverse event that occurred was a recurrence of chronic back pain occurring approximately 6 weeks after dosing . 3. No serious adverse events have been observed in the Emerge study at the time of the data analysis. At the time of the analys is, a total of 4 serious adverse events have been recorded across all studies of DT120 ODT, including an SAE deemed treatment - related, resulting in an SAE rate of approximately 0.6% acros s studies and populations. 4. Suicidality assessment based on changes in C - SSRS. AE: adverse event; ODT: orally disintegrating tablet; SAE: serious adverse event; TEAE: treatment - emergent adverse event ▪ AE profile consistent with prior studies of DT120 ▪ 99% of adverse events (AEs) were mild - to - moderate in severity 2 ▪ Most treatment emergent AEs (TEAEs) occurred and resolved on dosing day ▪ No TEAEs led to study withdrawal Favorable tolerability profile No SAEs 3 No suicidal behavior or suicidality signal 4 ▪ No serious adverse events (SAEs) ▪ No suicidal or self - injurious behavior ▪ No indication of increased suicidal ideation or suicide - related risk 19 Emerge Topline Results | June 2026

Emerge Topline Results | June 2026 20 Adverse Events were Mild - to - Moderate in Severity with No TEAEs Leading to Discontinuation 1 Placebo ODT n=74 DT120 ODT n=75 Adverse Event 42 (57%) 74 (99%) Any TEAE 31 (74%) 45 (61%) Mild 11 (26%) 28 (38%) Moderate 0 1 (1%) 2 Severe 24 (32%) 74 (99%) Any Study Drug - Related TEAE 15 (20%) 71 (95%) Any Adverse Event of Special Interest (AESI) 0 0 Any Treatment - Emergent SAE 0 0 Any TEAE Leading to Discontinuation 0 0 Any TEAE Leading to Death 1. Source: Emerge study documents. Safety population in study part A. 2. Severe adverse event was a recurrence of chronic back pain occurring approximately 6 weeks after dose. AESI: adverse event of special interest; ODT: orally disintegrating tablet; SAE: serious adverse event; TEAE: treatment - emergent adverse event

21 Most Common (≥10%) TEAEs Demonstrate Favorable Tolerability Profile of DT120 ODT 1 Emerge Topline Results | June 2026 Placebo ODT (n=74) DT120 ODT (n=75) TEAEs with Incidence ≥10% After Dosing Day Dosing Day After Dosing Day Dosing Day 0 2 (3%) 0 48 (64%) Illusion 0 3 (4%) 0 22 (29%) Euphoric Mood 0 2 (3%) 0 20 (27%) Nausea 2 (3%) 2 (3%) 9 (12%) 12 (16%) Headache 0 2 (3%) 0 12 (16%) Feeling of Relaxation 0 0 2 (3%) 11 (15%) Anxiety 0 1 (1%) 1 (1%) 11 (15%) Feeling Abnormal 0 1 (1%) 1 (1%) 10 (13%) Thinking Abnormal 0 1 (1%) 0 9 (12%) Crying 0 0 0 9 (12%) Disorientation 0 1 (1%) 0 9 (12%) Dizziness 0 1 (1%) 0 9 (12%) Paraesthesia 0 0 1 (1%) 8 (11%) Emotional Disorder 0 2 (3%) 0 8 (11%) Blood Pressure Increase 0 1 (1%) 0 8 (11%) Feeling of Body Temperature Change 0 1 (1%) 0 8 (11%) Hallucination, Visual 0 0 2 (3%) 6 (8%) Insomnia 1. Source: Emerge study documents. Safety population in study part A (through week 12). ODT: orally disintegrating tablet; TEAE: treatment - emergent adverse event

22 1. Source: Emerge study documents. Safety population in study part A. Time at which participant first meets End of Session Chec kli st criteria. ODT: orally disintegrating tablet; EoSC: End of Session Checklist DT120 ODT Dosing Session Duration Supports Translation into Clinical Practice 1 Emerge Topline Results | June 2026 57% 72% 87% 100% 0% 20% 40% 60% 80% 100% Hour 5 Hour 6 Hour 7 Hour 8 Time to End of Session Checklist (EoSC) Clearance Key Highlights ▪ Average time to clearance of EoSC of 5.8 hours ▪ Over half of participants cleared EoSC at hour 5 ▪ All participants cleared EoSC by hour 8

Phase 3 Emerge Topline Results Part B – Interim Analysis Dan Karlin, MD Chief Medical Officer

24 1. Based on interim analysis as of May 21, 2026. Interim analysis based on partial data and subject to change. 2. Extension population includes participants with at least one Part B visit completed. ITT: intent to treat; ODT: orally disintegrating tablet Part B Disposition Emerge Topline Results | June 2026 ▪ Safety population (n=149) ▪ ITT population (n=149) Part A Progress at Time of Interim Analysis Part B Randomized n=149 DT120 ODT n=75 Placebo ODT n=74 DT120 ODT up to 4 times n=44 in Extension Population 2 ▪ Through Week 28 (n=32) ▪ Through Week 36 (n=19) ▪ Through Week 52 (n=3) ▪ Through Week 28 (n=28) ▪ Through Week 36 (n=13) ▪ Through Week 52 (n=2) DT120 ODT up to 4 times n=50 in Extension Population 2

25 1. Based on interim analysis as of May 21, 2026. Extension population. Interim analysis based on partial data and subject to c han ge. 2. ITT population who entered Part B. Data based on Week 12 in Part A. CGI - S: Clinical Global Impressions – Severity Scale; ITT: intent to treat population; MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegrating tablet Part B Enrollment & Baseline Characteristics 1 Emerge Topline Results | June 2026 Total n=94 Placebo ODT n=44 DT120 ODT n=50 Demographic (Part B) 2 44.5 42.7 46.2 Mean age (years) 50% 50% 50% Sex, female (%) 65% 68% 62% Race (% white) 26.5 (10.0) 29.7 (8.5) 23.5 (10.4) MADRS score at Part B Entry 4.0 (1.1) 4.4 (0.8) 3.6 (1.2) CGI - S score at Part B Entry

26 1. Based on interim analysis as of May 21, 2026. ITT Part A+B population. Interim analysis based on partial data and subject t o c hange. 2. Only includes participants who received DT120 ODT in Part A. 3. n is the number of participants in the Extension population who had the specified number of doses up to the corresponding vis it. ODT: orally disintegrating tablet; OLTx: open - label treatment Treatment Patterns in Part B Provide Early Insights into Paradigm beyond 12 Weeks 1,2 Emerge Topline Results | June 2026 Summary of Cumulative DT120 ODT Doses through Week 28 Week 28 Week 24 Week 20 Week 16 n=50 n=45 n=38 n=32 DT120 ODT in Part A 3 n=44 n=39 n=35 n=28 Placebo ODT in Part A 3 Part A Dose only One OLTx Two OLTx Three OLTx Four OLTx

27 1. Based on interim analysis as of May 21, 2026. ITT Part A+B population with treatment policy strategy. Interim analysis base d o n partial data and subject to change. 2. n is the number of participants in the ITT Part A+B population with non - missing MADRS score at Baseline and the respective visit . LS Mean: least squares mean; MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegrating tablet MADRS Scores Improve Further with Additional Treatments in Part B Emerge Topline Results | June 2026 -20 -15 -10 -5 0 Week 0 Week 4 Week 8 Week 12 Week 16 Week 20 Week 24 Week 28 Mean Change in MADRS score MADRS Scores through Week 28 1,2 DT120 ODT in Part A Placebo ODT in Part A Part A Part B 28 32 32 47 66 65 75 23 29 38 45 60 64 74 DT120 ODT, n= Baseline Placebo ODT, n= First Open - Label Dosing

28 Subsequent Treatments Further Improve Response and Remission Rates through Week 28 1,2 Emerge Topline Results | June 2026 Remission Rates in Part B Response Rates in Part B 1. Source: Emerge study documents. ITT population. 2. Only includes participants who received DT120 ODT in Part A. MADRS: Montgomery - Åsberg Depression Rating Scale MADRS Improvement ≥ 50% MADRS Improvement ≥ 25% 27% 26% 31% 44% 50% 50% 51% 66% 59% 75% 0% 10% 20% 30% 40% 50% 60% 70% 80% Week 12 Week 16 Week 20 Week 24 Week 28 15% 15% 22% 28% 46% 27% 32% 41% 47% 54% 0% 10% 20% 30% 40% 50% 60% 70% 80% Week 12 Week 16 Week 20 Week 24 Week 28 MADRS ≤ 12 MADRS < 20 28 32 32 47 66 n= 28 32 32 47 66 n=

Next Steps Rob Barrow Chief Executive Officer

Emerge Topline Results | June 2026 30 Building Potentially Practice - Changing Evidence 1. Clinical study designs subject to change based on ongoing regulatory discussion and review, including of Phase 3 clinical tri al protocols DB: double blind; HAM - A: Hamilton Anxiety Rating Scale; MADRS: Montgomery - Åsberg Depression Rating Scale; ODT: orally disintegra ting tablet; OL: open - label; RCT: randomized controlled trial; Δ : placebo - adjusted delta Generalized Anxiety Disorder (GAD) Major Depressive Disorder (MDD) n=214 1 :1 randomization Enrollment Complete n=245 2:1:2 randomization Enrollment Complete n=149 1:1 randomization Positive Study Target n=165 1 2:1:2 randomization Enrolling Anticipated Topline Readout Early 3Q 2026 Anticipated Topline Readout Late 3Q 2026 n=198 1 :1:1:1:1 randomization Positive Study Phase 2b 4 Doses of DT120 vs. Placebo DT120 ODT vs. Placebo - 7.7 HAM - A at Week 12 (p<0.01) Continued momentum across complementary studies heading into upcoming Phase 3 readouts Primary endpoint: HAM - A at Week 12 Primary endpoint: HAM - A at Week 12 DT120 ODT vs. Placebo including 50 µg control - 8.1 MADRS at Week 6 (p<0.0001) DT120 ODT vs. Placebo DT120 ODT vs. Placebo including 50 µg control Primary endpoint: MADRS at Week 6 Study MMED008

Emerge Topline Results | June 2026 31 Opportunity to Deliver Significant Impact and Value Creation 1 1. Ringeisen, H., et al. (2023). Mental and Substance Use Disorders Prevalence Study (MDPS): Findings Report, Zhou, Y,. Et al. (20 17). Nature. Comorbid generalized anxiety disorder and its association with quality of life in patients with major depressive disorder. RTI International and current U.S. Census data and internal company estimates. Veeva COMPASS Open Claims An alysis Data on File, 2017 – 2025. 2. Assuming median Spravato® surrogate pricing range; the price of DT120 ODT has not been established. Addressable market means potential 42,000 patient impact & $2 billion revenue opportunity per 1% penetration 2 50 million US Adults with GAD / MDD 26 million Diagnosed with GAD / MDD 13 million Rx Treated 4.2 million Failed by 2+ Rx Strong Patient Desire & Willingness Large & Expanding Treatment Network Payer Understanding & Intent Large & Growing Unmet Need

32 Building a Psychiatry Powerhouse with Two Distinct Drivers 1 1. Timing estimates subject to clinical progress and regulatory interactions. ASD: autism spectrum disorder; GAD: generalized anxiety disorder; MDD: major depressive disorder; ODT: orally disintegrating tab let; TLR: topline data readout Clinical & Regulatory Execution 2028 2027 2026 Commercial Execution Value Creation Expanding Site of Care Engagement & Commercial Footprint Accelerating Scheduling & Reimbursement Optimizing Patient Care Model Voyage TLR early 3Q 2026 Initial DT402 Data in ASD (2026) Panorama TLR late 3Q 2026 NDA for DT120 ODT Ascend TLR Commercial Launch GAD & MDD Emerge Topline Results | June 2026 Positive Emerge Topline Data

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