Healingmental health disorders so that everyone everywhere can live a more fulfilled life. Company Overview Company Overview – June 2024

All references in this presentation to “we”, “us”, “our”, “atai”, or the “Company” refer to ATAI Life Sciences N.V. and its consolidated subsidiaries, unless the context otherwise requires. This presentation contains forward-looking statements within the meaning of the private Securities Litigation Reform Act of 1995. We intend such forward-looking statements to be covered under by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended.” All statements other than statements of historical facts contained in this presentation, including statements regarding our future results of operations and financial position, industry dynamics, business strategy and plans and our objectives for future operations, are forward-looking statements. 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atai Life Sciences: Healing mental health disorders so that everyone everywhere can live a more fulfilled life Highlights 03 1 Mental health disorders are one of the largest global health burdens; in 2019, 1 in every 8 people, or approx. 1 billion people around the world, were living with a mental disorder.1 3 Eight clinical-stage psychedelic and non-psychedelic programs and strategic investments, each with a robust package of prior clinical evidence. 2 atai’s objective is to enable mental health patients to achieve clinically meaningful and sustained behavioral change through developing innovative, rapid-acting and durable therapeutics. 4 Validated operating model and ability to capture value: IPO of COMPASS Pathways in 2020 and licensing deal between Otsuka and atai subsidiary Perception Neuroscience in 2021. 5 Cash and cash equivalents, marketable securities, and committed term loan funding expected to provide runway into 2026.2 1 World Health Organization 2 Committed term loan funding includes $45M of additional capital that can be drawn not subject to milestones under the facility with Hercules Capital; marketable securities includes money market funds, U.S. Treasury securities, commercial paper, corporate notes/bonds, U.S. government agencies securities, and public equities

Our strategy to be delivered through a robust portfolio of psychedelic and non-psychedelic drug development programs and strategic investments Drug Development Programs and Strategic Investments PSYCHEDELIC PROGRAMS & STRATEGIC INVESTMENTS Preclin Phase 1 Phase 2 Phase 3 Programs / Investments RL-007 / Pro-cognitive neuromodulator3 GRX-917 / Deuterated etifoxine COMP3601 / Psilocybin ELE-1012 / Psilocin VLS-01 / DMT EMP-01 / R-MDMA EGX-A & EGX-B / Novel 5-HT2A Receptor Agonists BPL-0032 / 5-MEO-DMT IBX-210 / Ibogaine Primary Indication Cognitive Impairment Associated with Schizophrenia Generalized Anxiety Disorder Treatment-Resistant Depression Major Depressive Disorder Treatment-Resistant Depression Undisclosed Undisclosed Treatment-Resistant Depression Opioid Use Disorder NON-PSYCHEDELIC PROGRAMS 2 Strategic Investment in Beckley PsyTech 1 Strategic Investment in Compass Pathways 3 RL-007 compound is (2R, 3S)-2-amino-3-hydroxy-3-pyridin-4-yl 1-pyrrolidin-1-yl-propan-1-one(L)-(+) tartrate salts Strategic Investment

We expect to deliver several meaningful R&D milestones anticipated across our key programs and strategic investments through 2024 and 20251 Upcoming Catalysts All dates provided are as estimated 05 Achieved and expected milestones1(2024-25) BPL-003Ph 2a OL (TRD) Part 1 data 2025 H2’24 H1’24 VLS-01Ph 1b first participant dosed ELE-101Ph 1/2a OL (MDD) initial data COMP360Ph 3 (TRD) Pivotal Trial 1 topline data COMP360Ph 3 (TRD) Pivotal Trial 2 topline data (mid’25) COMP360Ph 2 (PTSD) data (Spring ’24) BPL-003Ph 2a OL (AUD) data (mid’24) RL-007Ph 2b (CIAS) topline data (mid’25) VLS-01Ph 1b topline data BPL-003Ph 2b (TRD) patient recruitment completed   IBX-210Ph 1/2a initiation  VLS-01Ph 2 initiation (around YE’24)

Programs in Depression BPL-003, VLS-01, COMP360, ELE-101 06

A diverse portfolio of differentiated psychedelic assets to address the heterogeneity of patients who suffer from depression atai’s Depression Portfolio Comparison Associated Program Compound Primary Indication Route of Administration Receptor binding affinity (5-HT2A : 5-HT1A )1 Rapid Onset of Treatment Effect Appr. Duration in clinic VLS-01 DMT TRD Oral transmucosal film 3.4 ~2h BPL-003 5-MeO-DMT TRD Intranasal 0.01 ~2h ELE-101 Psilocin MDD Intravenous 2.0 ~2h COMP360 Psilocybin2 TRD Oral 2.0 ~6h 1 Besnard et al. 2012 // 2 Psilocybin is not present in the body in meaningful concentrations after oral consumption // Abbreviations: TRD = Treatment Resistant Depression; MDD = Major Depressive Disorder 07

atai’s focus is on psychedelics with the potential to leverage the 2-hour interventional psychiatry treatment paradigm successfully established by Spravato® Commercial Positioning Anticipated in-clinic time based on duration of subjective effects1 (in hours) Illustrative Spravato® BPL-003 / VLS-01 / ELE-101 Multi-dose 5-MeO-DMT Psilocybin + analogs MDMA LSD ~2 ~2 ~2 to 6* ~6 ~6 to 8 ~8 to 12 BPL-003, VLS-01 and ELE-101 have the potential in depression to offer a predictable, single-dose model administered within the 2-hour in-clinic treatment paradigm established by Spravato® 1 We anticipate this facilitates more scalable adoption and allows clinics to accommodate a greater number of patients daily, compared to psychedelics with longer duration subjective effects 2 Key Takeaways This may ultimately drive improved patient convenience and treatment access in the >4,000 certified delivery clinics2 for Spravato® with proven reimbursement and logistics pathways 3 Subject to further validation through future clinical studies and real-world evidence https://www.spravatohcp.com/#find-a-center * If multi-dose required Anticipated hours in-clinic1 08

BPL-003 (5-MeO-DMT) for TRD & AUD 09 Strategic Investment into Beckley Psytech

Beckley Psytech’s BPL-003 had a favorable safety profile and was well tolerated in the Phase 1 SAD study, with no observed serious or severe adverse events BPL-003: Phase 1 Results 1 n = number of subjects reporting at least one TEAE in that category, % - rounded proportion of cohort total 10 Placebo N=13 BPL-003 dose (N=31) GRX-917 150 mg N=9 GRX-917 200 mg N=9 GRX-917 300 mg N=8 All GRX-917 N=43 Total N=44 1 mg N=4 2.5 mg N=4 4mg N=4 6 mg N=4 8 mg N=5 10mg N=5 12 mg N=5 Any TEAEs 2 1 1 4 3 4 2 4 21 Nasal discomfort 1 2 2 2 3 10 Nausea 2 1 2 1 1 7 Vomiting 2 1 2 5 Headache 1 1 2 4 Administration site pain 1 1 2 Chest discomfort 1 1 Dizziness 1 1 Pyrexia 1 1 Gastroenteritis 1 1 Back pain 1 1 Hypoesthesia 1 1 Limb discomfort 1 1 Tremor 1 1 Lacrimation Increased 1 1 Restlessness 1 1 BPL-003 Phase 1 Treatment-Emergent Adverse Events (TEAEs)1 Results from the C-SSRS showed participants experienced no increase in suicidal thoughts, intentions or behavior. There were no severe or serious adverse events observed, and 89.5% TEAEs were mild and 10.5% were moderate in severity. 1 2 4 3 Key Takeaways 5 Blood pressure and heart rate increases were transient and resolved within 90 min without intervention. None were considered clinically significant. Most common TEAEs (>10%) were nasal discomfort, nausea, vomiting, and headache. TEAEs did not appear to correlate with dose. There were no clinically significant findings for laboratory parameters, vital signs, ECGs or physical examinations.

12mg (n=5) 10mg (n=5) 8mg (n=5) 6mg (n=4) 4mg (n=4) 2.5mg (n=4) 1mg (n=4) Mean plasma concentration levels (ng/ml) Time post-dose (minutes) BPL-003 Phase 1 Pharmacokinetic Profile Pharmacokinetics (PK) Exposure was dose-proportional Rapid onset with mean Tmax of 6-17 min Mean half life of 15-30 min Pharmacodynamics (PD) Subjects were psychedelic naive All subjects on doses ≥6mg achieved intensity scores ≥7 Perceptual effects generally fully resolved within 60 - 90 mins BPL-003 Phase 1 Subjective Intensity Ratings 0 12 30 60 90 12mg (n=5) 10mg (n=5) 8mg (n=5) 6mg (n=4) Time post-dose (minutes) Mean subjective drug intensity (SDI) Results from the completed BPL-003 Phase 1 study demonstrated a dose proportional PK/PD profile with perceptual effects generally resolving within 90 min BPL-003: Phase 1 Results 0 12 30 60 90 Source: internal Beckley Psytech data Abbreviations: SAD = Single Ascending Dose; PK = Pharmacokinetic; PD = Pharmacodynamic 11 Dose range taken forward to Phase 2 Key Takeaways

Completed Part 1 of an open-label Phase 2a study investigating 10mg of BPL-003 as a monotherapy for TRD patients BPL-003: Phase 2a Clinical Trial Design Abbreviations: MADRS = Montgomery–Åsberg Depression Rating Scale Screening Part 1: Monotherapy Open label Day 2 85 Completed Q1 2024 Phase 2a study design Single dose of BPL-003 29 STUDY DETAILS Open-label study evaluating a single dose of BPL-003 nasal spray, in patients with moderate-to-severe TRD KEY INCLUSION CRITERIA Montgomery-Asberg Depression Rating Scale (MADRS) score ≥24 Part 1: willing and able to discontinue current antidepressants Part 2: on current stable dose of antidepressant SSRI therapy KEY OBJECTIVES Primary Endpoint: Safety and tolerability of BPL-003 Other Secondary Endpoints: MADRS change through Week 12 Remission and response rates through Week 12 12 Part 2: Adjunct to SSRIs Initiated Q1 2024

BPL-003 produced meaningful clinical response and durable remission rates after just a single dose, and was generally well tolerated with no serious adverse events BPL-003: Phase 2a Results Source: internal Beckley Psytech data Response rate defined as ≥50% reduction in MADRS score and Remission rate defined as MADRS score ≤10 * Prior to data analysis, one subject (from total of 12 patients) was determined not to meet multiple per protocol eligibility criteria and was excluded from the efficacy analysis. 13 BPL-003 PHASE 2A INITIAL RESULTS Response and remission rate1 in TRD patients after a single dose of BPL-003 Response and Remission rate1,2 Time post-dose 55% of patients achieved clinical response on Day 2 and this rate of response was maintained at Week 12 1 Key Takeaways At Week 4, 55% of patients achieved both clinical remission and response 2 Day 2 Week 4 Week 12 45% Response Rate (n = 11*) Remission Rate (n = 11*) 3 4 Acute effects resolved within an average time of less than 2 hours Most common AEs (>10%) were nasal discomfort, headaches, nausea and vomiting, broadly consistent with Phase 1 findings

BPL-003 is actively recruiting for its ongoing Phase 2b study, a randomized, quadruple-masked, monotherapy study in 225 moderate to severe TRD patients BPL-003: Phase 2b Clinical Trial Design 1 Patients entering the open-label extension are randomized 1:1 to receive either a single 12mg dose or a biphasic 4mg and 8mg dose approximately 10 minutes apart Abbreviations: MADRS = Montgomery–Åsberg Depression Rating Scale; CGI-S = Clinical Global Impressions-Severity; PGIC = Patient's Global Impression of Change; EQ-5D = EuroQol-5D Randomization (1:1:1; n=225) Day 0 2 29 57 Wk-8 Washout 12 mg1 Core Study (8 weeks) Primary Analysis 29 57 Patient recruitment expected to be completed for Ph 2b (TRD) in 2H24 (first patient dosed Oct 2023) Open label extension (8 weeks) 0.3 mg (n=75) 8 mg (n=75) 12 mg (n=75) 1st Dose 2nd Dose KEY INCLUSION CRITERIA Patients with moderate to severe TRD Hamilton Depression Scale (HAM-D) >= 19 Willing and able to discontinue current antidepressants KEY OBJECTIVES Primary Endpoint: MADRS change from baseline at Week 4 Other Secondary Endpoints: MADRS change from baseline at Day 2, Week 1 and Week 8 CGI-S, PGIC, EQ-5D 8 14 1 1 2

VLS-01 (DMT) for TRD 15

Potential for rapid onset, durable efficacy, and designed to fit within 2-hour in-clinic treatment paradigm VLS-01: Product Overview World Health Organization Salzer, “National Estimates of Recovery-Remission From Serious Mental Illness”, Psychiatry Online (2018) Abbreviations: OTF = Oral transmucosal film; PK = Pharmacokinetic; PCT = Patent Cooperation Treaty Lead indication overview ~300m Global suﬀerers of depression in 20191 33% Patients who have inadequate response or relapse after current treatments2 Depression is a mood disorder that affects the thoughts and behavior of an individual, leading to psychological, physical, and social problems Treatment resistant depression (TRD) is diagnosed after two failed courses of antidepressants FDA approved depression treatments can be characterized by a slow onset, long-term side effects and inadequate response rate Global disease burden VLS-01 Key Product Features Short duration of psychedelic effect with improved tolerability and convenience from OTF delivery relative to other psychedelics in development for depression Designed for rapid onset, sustained efficacy, and to fit within a two-hour in-clinic treatment paradigm Optimized OTF formulation is designed to improve the PK profile and the patient and provider experience DMT (N,N-Dimethyltryptamine) in an oral transmucosal film (OTF) Lead: Treatment Resistant DepressionPotential expansions: Eating Disorders, Substance Use Disorders Phase 1b first participant dosed in 1Q’24 Phase 1b trial results anticipated in 2H’24 Phase 2 study anticipated to initiate around YE’24 PRODUCT INDICATIONS CURRENT STATUS INTELLECTUAL PROPERTY Granted U.S. patent covering OTF administration of DMT, supported by several pending U.S. and PCT patent applications 16

Double-blind, randomized placebo-controlled trial with DMT in 29 patients with TRD demonstrated rapid & statistically significant changes on HAM-D & MADRS VLS-01: Efficacy in Randomized Control Trial of DMT in TRD PRIOR CLINICAL EVIDENCE (THIRD PARTY STUDY1) Double-blind, randomized placebo-controlled trial of Ayahuasca (DMT is major active ingredient) in 29 patients with TRD Placebo N, N-DMT P<.0001 p<.05 p<.05 Baseline Day 1 Day 2 Day 7 45 40 35 30 25 20 15 10 5 0 MADRS Score Note: TRD = Treatment Resistant Depression; DMT = N,N-Dimethyltryptamine 1. Palhano-Fontes et al. “Rapid antidepressant eﬀects of the psychedelic ayahuasca in treatment-resistant depression”, Psychol Med (2019) Summary: A single administration of .36 mg/kg met both primary and key secondary efficacy endpoints by demonstrating rapid and statistically significant changes on depression severity measures of HAM-D & MADRS Primary endpoint (HAM-D - not shown): N,N-DMT arm achieved the primary endpoint of a statistically significant difference in depression severity relative to placebo (p<.05). 1 2 There were no serious adverse events reported. 4 Key secondary endpoint (MADRS – see left): rapid and statistically significant differences were observed at all timepoints assessed, including as early as Day 1 and through Day 7. MADRS is a potential registrational endpoint. 3 Key Takeaways 17

Phase 1 results of VLS-01 showed it was safe and well-tolerated with dose-dependent increases in exposure VLS-01: Phase 1 Clinical Trial Design & Results Note: IV = Intravenous; OTF = Oral Transmucosal Film; PK / PD = Pharmacokinetic / Pharmacodynamic; DMT = N,N-Dimethyltryptamine; IV = Intravenous Program status: Phase 1b first participant dosed in Q1 24. Topline results expected 2H 24. Phase 2 study in TRD patients anticipated to initiate around YE’24 IV VLS-01: PK / PD results were consistent with the known pharmacological profile of DMT, producing robust exposure-dependent increases in the subject intensity of psychedelic experience. Part 3 (OTF VLS-01) Part 2 (OTF VLS-01)  Part 1 (IV VLS-01)  STUDY DESIGN: OTF VLS-01: Produced generally dose-dependent increases in exposure, approaching that seen with IV administration, alongside subjective psychedelic experiences in most patients. OTF VLS-01: 160mg with a backing layer via buccal administration experienced the most robust and consistent increases in exposure and subjective effects compared to the other OTF cohorts, with results comparable to the 30 mg IV cohort of DMT. Phase 1 PK / PD RESULTS:  18

COMP 360 (Psilocybin) for TRD, PTSD and Anorexia 19 Strategic Investment into Compass Pathways

COMP360 Phase 2b trial showed a rapid, sustained reduction in depressive symptoms PRODUCT PHARMA-COLOGY PRODUCT FEATURES INDICATIONS CURRENT STATUS INTELLECTUAL PROPERTY Oral Psilocybin (COMP360) 5-HT2A-R agonist Rapid onset, potential for sustained efficacy after single dose Primary: Treatment Resistant Depression, Anorexia Nervosa, PTSD Potential: Major Depressive Disorder, Autism, Bipolar Disorder, Chronic Cluster Headache Phase 3 pivotal trial 1 data expected summer-24 Phase 3 pivotal trial 2 data expected mid-25 Proprietary formulation of synthetic psilocybin, COMP360 SUMMARY: COMP360 HIGHLIGHT COMP360 demonstrated eﬃcacy in reducing depressive symptom severity with rapid and durable response in Phase 2b study PRIOR EVIDENCE IN HUMANS (COMP360 PHASE 2b) 9,565,774 shares1 OWNERSHIP Note: MADRS = Montgomery-Åsberg Depression Rating Scale; COMP360 = a proprietary high-purity, polymorphic crystalline formulation of psilocybin; In COMPASS’s model of psilocybin therapy, COMP360 is administered in conjunction with psychological support from specially trained therapists. Ownership as of March 27th, 2024 Post-hoc analysis showed results were also positive at the other time points listed for 25mg dose, however, the nonsignificant finding for the comparison between the 10mg group and the 1mg group terminated significance testing based on the prespecified hierarchical test procedure for all subsequent key secondary efficacy end points. 20 Primary Endpoint

COMPASS Pathways is currently conducting a Phase 3 pivotal program, with topline data expected in 4Q 2024 and mid 2025 COMP360: Phase 3 Trial Designs Source: Compass Pathways Capital Markets Day presentation as of May 11th, 2023 Primary endpoint = Change from baseline in MADRS total score at week 6 The participant population (TRD definition and core inclusion / exclusion criteria) remains unchanged compared to Phase 2b Week 6 Primary endpoint1 Week 3 Proceeded by long-term follow up Pivotal study 1 Single dose monotherapy (COMP 005) COMP360 25mg Placebo Randomization = 2:1 Target N2 = 255 Topline data expected: 4Q 2024 Pivotal study 2 Fixed repeat dose monotherapy (COMP 006) COMP360 25mg COMP360 25mg COMP360 10mg COMP360 10mg COMP360 1mg COMP360 1mg Randomization = 2:1:1 Target N2 = 568 Topline data expected: Mid 2025 Week 0 Week 0 Proceeded by long-term follow up Pivotal Phase 3 Trial Designs Week 6 Primary endpoint1 21

Open-label phase 2 study of COMP360 in post-traumatic stress disorder demonstrated an early onset and sustained improvement in PTSD symptoms at week 4 and week 12 COMP360: Phase 2 PTSD Results 22 Source: Compass Pathways NCT05312151 Response rate defined as a reduction of ≥ 15 points in CAPS-5 score Remission rate defined as a total CAPS-5 ≤ 20 Mean SDS total score of 22.7 at baseline COMP360 PHASE 2 PTSD STUDY TOPLINE RESULTS Summary of change in CAPS-5 mean total score Mean total score on CAPS-5 (+/- SD) Time post-dose Phase 2 study was a multicenter open-label, single administration of 25mg COMP360 with psychological support (n=22)1 1 Key Takeaways 81.8% response rate and 63.6% remission rate at week 4 with a 77.3% response and 54.5% remission rate at week 122,3 2 Baseline Week 12 Week 4 3 4 Sheehan Disability Scale (SDS), a measure of functional impairment, improved with a reduction from baseline of 11.7 points at week 4 and 14.4 points at week 124 Administration was well tolerated, with no serious adverse events observed CAPS-5 mean total score

ELE-101 (Psilocin) for MDD 23 Strategic Investment into Beckley Psytech

Potential benefits of psilocybin’s active moiety in an optimized delivery and treatment model ELE-01: IV Psilocin 1 Psilocin simulations based on primary data from Brown et al. 2017, Madsen et al . 2019, Hasler et al. 1997, and Carhart-Harris et al. 2011. 2 Holze F. et al (2023). Pharmacokinetics and Pharmacodynamics of Oral Psilocybin Administration in Healthy Participants. Clin Pharmacol Ther. Psilocin pharmacokinetics for IV psilocin (simulated) vs. oral psilocybin1 Typical plasma psilocin concentrations at effective dose of 25mg psilocybin1 Perceptual threshold2 Expected benefits of IV psilocin vs oral psilocybin: Reduced variability Shorter-half life = shorter duration of psychedelic effect, anticipated to be <2 hours 24

Randomized, Phase 1 dose-escalation study in healthy volunteers followed by Phase 2a open-label study in MDD ELE-101: Phase 1/2a Clinical Trial Design ELE-101 Phase 1/2a – Part A Key Objectives: Safety and tolerability Assessment of PK & PD Target concentration of psilocin in <2 minutes Consistency of subjective intensity Key Objectives: Safety and tolerability of ELE-101 in patients with moderate to severe MDD Key Secondary Endpoints: Assessment of MADRS change (Day 2, 4, 6, 15, 29) CGI-S, PGIC Single Ascending Dose ELE-101 Phase 1/2a – Part B Open-label MDD cohort Initial results anticipated in H1 2024 Screening Dose to be selected Open label Day 1 Day 29 Dose 1 Placebo Dose 2 Placebo Dose 3 Placebo Dose 4 Placebo Day 1 Day 7 Abbreviations: MADRS = Montgomery–Åsberg Depression Rating Scale; PK = Pharmacokinetics; PD = Pharmacodynamics; CGI-S = Clinical Global Impressions-Severity; PGIC = Patient's Global Impression of Change; MDD = Major Depressive Disorder 25

IBX-210 (IV-Ibogaine) for Substance Use Disorder 26

Post traumatic stress disorder and traumatic brain injury, respectively World Health Organization Salzer, “National Estimates of Recovery-Remission From Serious Mental Illness”, Psychiatry Online (2018) A single dose of ibogaine may support withdrawal and long-term relapse prevention in OUD patients Product Overview: IBX-210 for Opioid Use Disorder Lead indication overview ~3m US OUD Incidence in 20202 >100k Opioid-related deaths in US in 2022 Substance use disorders are highly prevalent and characterized by an inability to control the use of a legal or illegal drugs, such as opioids (including prescription opioids) or alcohol. Current standard of care for OUD primarily consists of psychosocial support and synthetic full and partial opioid receptor agonists (methadone & buprenorphine), where approximately 30% of patients achieve treatment success (defined as >80% illicit opioid free weeks). In addition, long-acting opioid antagonists (naltrexone) lead to a proportion of patients achieving treatment success. Global disease burden IBX-210 Key Product Features A single dose of ibogaine delivered in a monitored setting may support withdrawal and long-term relapse prevention in Opioid Use Disorder patients Prior clinical evidence: In third-party open label studies, ibogaine was associated with significantly reduced opioid cravings, both at discharge and at one month post treatment, as well as improved mood in patients with OUD In addition, a double-blind, placebo-controlled study in subjects with cocaine use disorder demonstrated a statistically significant benefit on urine confirmed relapse of a single administration of ibogaine compared to placebo Lead: Opioid Use Disorder (“OUD”)Potential expansions: Add’l Substance Use Disorders, PTSD, TBI1 Phase 1 oral ibogaine study completed in 3Q 23 IBX-210 Phase 1/2a study anticipated to initiate in H2 2024 PRODUCT INDICATIONS CURRENT STATUS INTELLECTUAL PROPERTY Issued and pending method of treatment claims for OUD IBX-210 is a novel IV formulation of ibogaine, which is an indole alkaloid with potential for clinical benefit through oneirophrenic effects 27

Results from an open-label study of 8-12 mg/kg of ibogaine in patients seeking detoxification from opioids and cocaine Clinical Evidence: Efficacy of ibogaine in Open-Label Safety & Efficacy Study PRIOR CLINICAL EVIDENCE (THIRD PARTY STUDY1) Note: TRD = Treatment Resistant Depression; DMT = N,N-Dimethyltryptamine; HCQ = Heroin Craving Questionnaire 1 Mash et al., “Ibogaine Detoxification Transitions Opioid and Cocaine Abusers Between Dependence and Abstinence: Clinical Observations and Treatment Outcomes” (2018) 1 2 Safety: Ibogaine was reported to be well tolerated with no serious adverse events. 4 Key Takeaways HCQ-29 Subscale Pre-dose (N=75) 5 4 3 2 1 0 Discharge (N=74) 1 Month (N=37) Emotionality(negative mood state) Compulsivity(lack of confidence in ability to quit) Purposefulness(desire of intent to use) Expectancy(expected positive benefits of drug use) Self-reported dimensions of craving Efficacy – Post-Acute Withdrawal Syndrome: signs and symptoms at post dose assessments were reduced compared to pre-dose baseline withdrawal severity measures. Objective signs of opioid withdrawal were mild and none were exacerbated at later time points. 3 Efficacy – Relapse Prevention (shown left): Opioid dependent patients had significant reductions in the mean scores of four HCQ-29 domains of craving measured at program discharge and out to 1 month for patients continuing through study completion. Cravings are an important mediator of relapse. Summary: A single-dose of ibogaine showed reductions in self-reported opioid cravings in 74 opioid dependent patients. 28

IBX-210 has the potential to become the first & best in-class treatment for OUD, minimizing risk of relapse SUMMARY IBX-210 could potentially become a paradigm-shifting therapy for Opioid Use Disorder (OUD) Current standard of care for OUD is medication therapy, requiring opioid substitutes that carry significant side effects Sustained relapse prevention Single dose administered in monitored setting, providing both withdrawal support and oneiric experience driving sustained remission Single Therapeutic Episode Minimal Abuse Potential No Opioid Side Eﬀects High Adherence / Low Risk of Relapse Cholinergic, glutamatergic and monoaminergic receptor modulator Mechanism of Action Ibogaine (IBX-210) Therapy Medication Assisted Therapy1 Daily therapy given in substitution of opioid in outpatient setting in attempt to wean oﬀ from opioid Mu-agonist Partial Mu-agonist Mu-antagonist Methadone Buprenorphine Naltrexone Withdrawal Support2 Therapies given for symptomatic management during supervised withdrawal (detoxiﬁcation) Alpha-2 agonist Alpha-2 agonist Clonidine Lofexidine Current strategies for withdrawal support have high rates of relapse Note: OUD = Opioid Use Disorder Source: Publicly available information, including company websites and clinicaltrials.gov, GlobalData, Evaluate Pharma (both as of 2022) Current Standard of Care Rarely used given high rates of relapse. Used primarily in institutional or penitentiary settings DemeRx 29

RL-007 for Cognitive Impairment 30

World Health Organization Schaffer et al., 2013 Bora et al, Cognitive Impairment in Schizophrenia and Affective Psychoses: Implications for DSM-V Criteria and Beyond GlobalData (as of 31/12/2023) Demonstrated consistent pro-cognitive effects in prior clinical trials, with a favorable safety profile in >500 subjects Product Overview: RL-007 for Cognitive Impairment Lead indication overview ~24m Global suﬀerers of Schizophrenia¹ >80% Patients with Schizophrenia experiencing significant cognitive impairment3 Cognitive impairment associated with schizophrenia (CIAS) is characterized by attention, learning, memory, and exec function deficits Such deficits result in cognitive function around 2.5 standard deviations below the mean of the general population2 CIAS is a common and major cause of disability in schizophrenia, with more than 80% of patients showing significant impairment3 No FDA approved treatments4 Global disease burden RL-007 Key Potential Product Features Pro-cognitive effects demonstrated across four prior clinical studies, including two Phase 1 and two Phase 2 trials Consistent “inverted-U” dose response across clinical & preclinical studies Demonstrated safety & tolerability with no evidence of sedative side effects across the 10 clinical studies in >500 subjects Oral, pro-cognitive neuromodulator Lead: Cognitive impairment associated with schizophrenia (CIAS)Potential expansions: Cognitive disorders including Alzheimer’s dementia and/or Autism Phase 2a CIAS trial completed in H2’21Phase 2b first patient dosed in 1Q’23 Phase 2b data expected in mid’25 PRODUCT INDICATIONS CURRENT STATUS INTELLECTUAL PROPERTY Issued composition of matter, formulation and method of use IP 31

Third-Party Phase 2 study in DPNP showed statistically significant positive cognitive signals (exploratory endpoints) Note: * = P< 0.05 vs Placebo; N=60 patients/treatment group; dosed TID = 3x/day dosing; randomized, cross-over design Clinical Evidence: Efficacy on Cognitive Endpoints in a Phase 2 Study Phase 2, randomized, placebo-controlled, crossover clinical study in subjects with diabetic peripheral neuropathic pain (DPNP) that assessed improvements in verbal learning and memory as an exploratory endpoint 4-week placebo periods were compared to 4-week RL-007 periods “Intermediate-dose escalation” RL-007 40mg (first week) to 80mg (n=60) “High-dose escalation” RL-007 150mg (first week) to 300mg (n=60) Background RL-007 showed statistically significant pro-cognitive effects on learning and memory within the “Intermediate-Dose escalation” 40mg to 80mg arm. 1 2 Key Takeaways Delayed recall 0.4 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 0.35 0.3 0.25 0.2 0.15 0.1 0.05 RL-007 (40 & 80 mg TID) RL-007 (150 & 300 mg TID) RL-007 (40 & 80 mg TID) RL-007 (150 & 300 mg TID) Cohen’s d effect size Diff. vs. Placebo Cohen’s d effect size Diff. vs. Placebo * * Direction of Improvement Direction of Improvement 0 3 The 40 to 80mg arm patients also reported a statistically significant improvement on the Cognitive and Physical Function Questionnaire (p = 0.021) Inverted U-shaped dose response whereby intermediate doses yield greater clinical activity is replicated and consistent with from prior clinical and preclinical studies Verbal learning 32

PHASE 2a TRIAL - EFFICACY DATA ON COMPONENTS MCCB COMPOSITE Signal of improvement n=7 n=8 n=8 n=8 Cohen’s d* (Symbol Coding): 20 mg: 0.79 40 mg: 0.56 80 mg: 0.38 *Active vs pbo T-Scores (Normalized for age, gender, and education level) atai’s Phase 2a study in CIAS demonstrated positive cognitive signals on a subset of MCCB neurocognitive endpoints Clinical Evidence: Efficacy Signals Reproduced in Phase 2a Study in CIAS Study demonstrated dose-related trends for improvements on each MCCB neurocognitive endpoints, including a Cohen’s d effect size of 0.79, 0.56 and 0.38 at the 20mg, 40mg, and 80mg, respectively, on the BACS Symbol Coding test. 1 Importantly, Symbol Coding is the most sensitive subcomponent and correlates with overall performance on the MCCB neurocognitive composite, the latter being a registrational endpoint and the primary endpoint for the on-going Phase 2b study of RL-007. 2 In addition, qEEG data was consistent with the prior clinical evidence and demonstrated increases in amplitude in the alpha band and in the alpha-slow wave index, markers of alertness believed to correlate with aspects of cognition. 3 Cognitive function was assessed in 31 patients with CIAS across four RL-007 cohorts (10, 20, 40 & 80mg). Patients received four doses of placebo followed by six doses of RL-007 over 4-days. Day 2 “pre-RL-007” was compared to Day 4 “post-RL-007”. The primary objectives of the single-blinded study was to confirm safety on-top of SOC and to identify signals of cognitive benefit in patients with CIAS, including on three MCCB sub-component neurocognitive tests, HVLT1, BACS Symbol Coding & Category Fluency Background Key Takeaways 1. Hopkins Verbal Learning Test 33

Clinical Trial Design: RL-007 Phase 2b Study Note: MCCB = MATRICS Consensus Cognitive Battery; BACS = Brief Assessment of Cognition in Schizophrenia; CIAS = Cognitive Impairment Associated with Schizophrenia; TID = 3x/day dosing Trial status: First patient dosed in 1Q’23, Topline data anticipated mid’25 Randomized, placebo-controlled study of RL-007 in ~234 patients with CIAS RL-007 TID (40mg) RL-007 TID (20mg) Placebo R Randomized 1:1:1 Primary Endpoint: MCCB neurocognitive composite score at Week 6 Key Secondary Endpoints: Select Individual Components of MCCB, including BACS Symbol Coding Clinical Global Impression Score Week 6 Day 1 34

GRX-917 for Anxiety Disorders 35

World Health Organization Anxiety and Depression Association of America (2021) GlobalData (as of 6/1/2023) - All recent approvals by the FDA have been reformulations of long-standing antidepressant and benzodiazepine options Designed to have rapid onset of anxiolytic activity but without the negative side effects seen with benzodiazepines Product Overview: GRX-917 for Anxiety Disorders Lead indication overview ~300m Anxiety disorder suﬀerers in 20191 #1 Most common mental health disorder1 Anxiety disorders develop when feelings of apprehension and unease persist over an extended period and potentially worsen over time 50% of US patients go untreated as a result of sub-optimal treatment options2 No FDA approved novel treatments over the past decade3 Global disease burden GRX-917 Key Product Features Demonstrated rapid onset activity of anxiolytic activity (non-deuterated etifoxine approved in France) Review of ~14m prescriptions in France underscores the strong safety track record for etifoxine Differentiated tolerability profile, with limited sedative, addictive and/or cognitive impairing properties, unlike benzodiazepines Deuterated etifoxine HCl oral dosage form (GRX-917) Lead: Anxiety Disorders (e.g., GAD, SAD, PTSD, etc.) Phase 1 trial completed in H2’22 Exploring partnership and external funding opportunities PRODUCT INDICATIONS CURRENT STATUS INTELLECTUAL PROPERTY Issued composition of matter on deuterated etifoxine (GRX-917) and corresponding methods of use 36

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