Generalized Anxiety DisorderPhase 2NCT07478744
A Phase 2a Efficacy, Safety, Tolerability, and PK Study of SYT-510 in Participants With Generalized Anxiety Disorder
A Phase 2 study testing SYT-510 in people with Generalized Anxiety Disorder, run by Synendos Therapeutics AG at 1 site in United Kingdom.
Trial summary
This is a single dose study to investigate the efficacy, safety, tolerability and the PK, of SYT-510 in participants who meet diagnostic criteria of GAD. This study represents an evaluation of the effects of SYT-510 in participants meeting DSM-5 GAD diagnostic criteria. Read more about this study
- Who is it for?
- Ages 18 to 55 years
- Conditions the study is for
- Generalized Anxiety Disorder
- What is being tested?
- SYT-510
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 24 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 22 Apr 2026to Jan 2027
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Males or females aged 18 to 55 years old (inclusive) at the date of signing the ICF.
- Participants who are currently unmedicated and meet the criteria for GAD as defined in the DSM-5 by using the MINI.
- Participants must be right-handed.
- BMI between 18 and 30 kg/m2, inclusive, at Screening and a minimum weight of 50 kg.
- Contraception use by men or women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.
- Participants must agree not to donate sperm or ova from the time of the first administration of study drug (T1, D2) until 3 months after the participant's last visit.
- Ability to provide written, personally signed, and dated informed consent to participate in the study, in accordance with the current version of the ICH GCP Guideline E6 and applicable regulations, before completing any study-related procedures.
- Have an understanding, ability, and willingness to fully comply with study procedures as detailed in the Study Protocol and ICF.
Who cannot join
- Current or past diseases (e.g., cardiovascular, pulmonary, gastrointestinal, hepatic, renal, metabolic, hematologic, neurologic, endocrine, immunologic, rheumatologic, dermatologic or other conditions) that may interfere with the execution of the conduct of the study, as per the Investigator's judgment.
- Participants with current or recurrent disease or treatment that can interfere with the absorption, metabolism, and elimination of SYT-510. Examples include participants with partial gastrostomy or impaired renal functions.
- Participants with significant learning difficulties, uncorrected visual and auditory problems and history of dyslexia.
- Participants with a current DSM-5 diagnosis of major depressive disorders or severe depressive symptoms determined by MADRS score > 20.
- Substance use disorder within the past 6 months before Screening.
- Any primary diagnosis other than GAD e.g., bipolar disorder, obsessive compulsive disorder, PTSD, psychotic disorder, cognitive impairment, or pervasive development disorder.
Show all 31Show fewer
- Any psychotic features, including dementia or delirium.
- Experienced suicidal ideation with some intent to act within the 6 months preceding screening or any history of suicidal behavior.
- Other current or relevant history of physical, neurological or psychiatric illness that may require treatment (e.g., any history of epilepsy).
- Participants with contraindications for MRI.
- Conditions that make the participant unlikely to fully comply with the requirements of the study or complete the study, or any condition that presents undue risk from the study drug or study procedures.
- Positive test for HBsAg, hepatitis C virus antibody, or human immunodeficiency virus antibody at Screening.
- Active systemic bacterial, viral, or fungal infection within 14 days prior to dosing on T1, D2 or presence of fever (confirmed body temperature > 38 ºC) within 14 days prior to dosing on T1, D2.
- Diagnostic Assessments
- Laboratory parameters outside of the laboratory normal range (hematology, biochemistry, coagulation, urinalysis), unless deemed NCS by the Investigator.
- Has vital signs outside of the following normal range at Screening or Baseline, unless considered NCS by the Investigator: supine SBP 90-140 mmHg, supine DBP 50-90 mmHg, supine PR 40-100 bpm.
- Has any clinically significant abnormalities in rhythm, conduction or morphology of resting ECG or clinically important abnormalities that may interfere with the interpretation of QTc interval changes, or values outside of the normal range, unless considered NCS by the Investigator.
- Positive test results for alcohol or drugs of abuse at Screening or Baseline. Prior/Concomitant Therapies
- Has used any prescription medication (excluding hormonal therapy for postmenopausal women or contraception for WOCBP) within 30 days prior to Screening and any medication for the treatment of anxiety within 6 months prior to screening.
- Consumption of herbal remedies or dietary supplements which may interact with the study drug (for example containing St. John's Wort) in the 30 days prior to first dose and until the end of the study.
- Use of cannabis, tetrahydrocannabinol or cannabidiol containing products in the 28 days before the Study T1, D2.
- Participants who have received a live vaccine within 30 days prior to the first dose administration or who plan to receive a live vaccine during the study period.
- Prior / Concurrent Clinical Study Experience
- Treatment with an investigational drug within 90 days or 5 half-lives preceding the first dose of trial intervention (or as determined by the local requirement, whichever is the longer) or will start any other investigational product or device study within 90 days after last study drug administration.
- Other Exclusion Criteria
- Known or suspected intolerance or hypersensitivity to the investigational product, any closely related compound, or any of the stated ingredients.
- History of significant allergic reactions (anaphylaxis, angioedema) to any product (food, pharmaceutical, etc.).
- Donation of blood or blood products within 90 days, or plasma within 7 days prior to study drug administration on T1, D2.
- Underwent general anesthesia in the 30 days prior to study drug administration on T1, D2.
- Nicotine consumption (in any form) equivalent to > 5 cigarettes or vapes per week.
- Weekly intake of more than 14 units of alcohol.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United Kingdom1 site, 1 recruiting
- Recruiting
SLaM
London
Principal Investigator
About this study
Official title: A Study Investigating the Efficacy, Safety, Tolerability, and Pharmacokinetics of a Single Dose of SYT-510 in Participants Who Meet DSM-5 Diagnostic Criteria for Generalized Anxiety Disorder
This is a single dose study to investigate the efficacy, safety, tolerability and the PK, of SYT-510 in participants who meet diagnostic criteria of GAD. This study represents an evaluation of the effects of SYT-510 in participants meeting DSM-5 GAD diagnostic criteria. As a single dose study, it is designed to evaluate the efficacy of SYT-510 on neurobiological and behavioral markers associated with anxiety and will inform the design of future clinical trials in anxiety disorders. By integrating efficacy / PD, safety, tolerability, and PK measures within the same study framework, the study enables the translational value of the program, ensuring a more comprehensive understanding of SYT-510 effects in patients with generalized anxiety disorders. The plan is to evaluate a single dose of SYT-510 as compared with its matching placebo in a two-way crossover design, separated by a washout period of 7 to 14 days.
- Conditions
- Generalized Anxiety Disorder
- Being tested
- SYT-510, Placebo
- Medical subject headings
- Generalized Anxiety Disorder
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SYT-510Drug
SYT-510 will be administered as a single oral dose in the morning with liquid.
PlaceboDrug
Matching placebo will be administered as a single oral dose in the morning with liquid.
| Study group | Role | What they receive |
|---|---|---|
| SYT-510 | Experimental | Not described Receives: Drug: SYT-510 |
| Placebo | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
BOLD fMRI signal in the amygdala in response to fearful stimuli
Measured: 7 hours post-dose on Day 2 Treatment period 1 and Day 2 Treatment period 2
Defensive behavior: Joystick Operated Runway Task (JORT) Flight Intensity
The JORT uses a force sensing joystick combined with a two-dimensional runway positioned vertically on a computer monitor to measure one-way active avoidance and two-way active avoidance in response to threat of a white noise burst. Each JORT session generates a time series datafile. These time series files are fed into custom programmed scoring software. This software calculates Flight Intensity and RAI for that session
Measured: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Defensive behavior: Joystick Operated Runway Task Risk Assessment Intensity
The JORT uses a force sensing joystick combined with a two-dimensional runway positioned vertically on a computer monitor to measure one-way active avoidance and two-way active avoidance in response to threat of a white noise burst. Each JORT session generates a time series datafile. These time series files are fed into custom programmed scoring software. This software calculates Risk Assessment Intensity for that session
Measured: 4 hours post-dose, Day 2 Treatment Period 1 and Day 2 Treatment period 2
Subjective dread during Joystick Operated Runway Task (JORT)
Dread rating on a scale of 1 (no threat) to 10 (maximum dread) .
Measured: 4 hours post-dose, Day 2 Treatment Period 1 and Day 2 Treatment period 2
Approach-avoidance learning: reward-punishment sensitivity index
Measured: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Approach-avoidance learning: punishment sensitivity index
Measured: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Default Mode Network connectivity (fMRI)
Measured: 7 hours post dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Reaction time to fearful faces (fMRI task)
Measured: 7 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Self reported State Trait Anxiety Inventory (STAI) subscale score
The STAI sub-scale is a questionnaire that consists of 20 self-report items that assess current symptoms of anxiety, each item is rated on a four-point Likert scale from "Not at all" to "Very much so".
Measured: 1 day post-dose, on Day 3 Treatment period 1 and Day 3 treatment period 2
Secondary outcomes (6)
EEG power across frequency bands
Measured: 3 and 6 hours post-dose
Plasma concentrations of endocannabinoids and ECS related biomarkers
Measured: pre-dose to 24 hours post-dose, Day 2 to Day 3 Treatment period 1 and 2
Maximum Observed Concentration (Cmax) of SYT 510
Measured: Up to 24 hours post-dose, Day 2 to Day3 Treatment period 1 and 2
Time of maximal plasma concentration (tmax) of SYT-510
Measured: From dosing to follow-up visit, up to 11 weeks
Area Under the SYT-510 concentration -time Curve (AUC) from time 0 to 24 hours
Measured: pre-dose to 24 hours post dose, on Day 2 to Day 3 Treatment periods 1 and 2
14. Incidence and severity of Treatment Emergent Adverse Events and Serious Adverse Events, changes and/or abnormalities in clinical laboratory tests, physical examination findings, vital signs, and ECGs.
Measured: From Day 2 treatment period 1 to follow-up visit, up to 11 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Mar 2026
- Study start22 Apr 2026
- Primary completionJan 2027 (estimated)
- Study completionJan 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Generalized Anxiety DisorderStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Synendos Therapeutics AG
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Allan Young, Principal investigator, SLaM
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07478744
- Sponsor's protocol ID
- SYN510CT-GAD201
- Other IDs
- 1013320
- Status last verified
- Jun 2026
- First submitted
- 9 Mar 2026
- Last updated
- 18 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 18 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Study Investigating the Efficacy, Safety, Tolerability, and Pharmacokinetics of a Single Dose of SYT-510 in Participants Who Meet DSM-5 Diagnostic Criteria for Generalized Anxiety Disorder
- ClinicalTrials.gov ID
- NCT07478744
- Acronym / sponsor ID
- SYN510CT-GAD201
- Conditions
- Generalized Anxiety Disorder
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- Synendos Therapeutics AGIndustry (pharma, biotech, devices)
- Study start
- 22 Apr 2026 (actual)
- Primary completion
- Jan 2027 (estimated)
- Study completion
- Jan 2027 (estimated)
- First posted
- 17 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a single dose study to investigate the efficacy, safety, tolerability and the PK, of SYT-510 in participants who meet diagnostic criteria of GAD. This study represents an evaluation of the effects of SYT-510 in participants meeting DSM-5 GAD diagnostic criteria. As a single dose study, it is designed to evaluate the efficacy of SYT-510 on neurobiological and behavioral markers associated with anxiety and will inform the design of future clinical trials in anxiety disorders. By integrating efficacy / PD, safety, tolerability, and PK measures within the same study framework, the study enables the translational value of the program, ensuring a more comprehensive understanding of SYT-510 effects in patients with generalized anxiety disorders. The plan is to evaluate a single dose of SYT-510 as compared with its matching placebo in a two-way crossover design, separated by a washout period of 7 to 14 days.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| SYT-510 | Experimental | Drug: SYT-510 |
| Placebo | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (8 listed)
- Males or females aged 18 to 55 years old (inclusive) at the date of signing the ICF.
- Participants who are currently unmedicated and meet the criteria for GAD as defined in the DSM-5 by using the MINI.
- Participants must be right-handed.
- BMI between 18 and 30 kg/m2, inclusive, at Screening and a minimum weight of 50 kg.
- Contraception use by men or women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.
Key exclusion criteria (31 listed)
- Current or past diseases (e.g., cardiovascular, pulmonary, gastrointestinal, hepatic, renal, metabolic, hematologic, neurologic, endocrine, immunologic, rheumatologic, dermatologic or other conditions) that may interfere with the execution of the conduct of the study, as per the Investigator's judgment.
- Participants with current or recurrent disease or treatment that can interfere with the absorption, metabolism, and elimination of SYT-510. Examples include participants with partial gastrostomy or impaired renal functions.
- Participants with significant learning difficulties, uncorrected visual and auditory problems and history of dyslexia.
- Participants with a current DSM-5 diagnosis of major depressive disorders or severe depressive symptoms determined by MADRS score > 20.
- Substance use disorder within the past 6 months before Screening.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| SYT-510SYT-510 will be administered as a single oral dose in the morning with liquid. | Drug | SYT-510 |
| PlaceboMatching placebo will be administered as a single oral dose in the morning with liquid. | Drug | Placebo |
Primary outcome
BOLD fMRI signal in the amygdala in response to fearful stimuli
Time frame: 7 hours post-dose on Day 2 Treatment period 1 and Day 2 Treatment period 2
Defensive behavior: Joystick Operated Runway Task (JORT) Flight Intensity
Time frame: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
The JORT uses a force sensing joystick combined with a two-dimensional runway positioned vertically on a computer monitor to measure one-way active avoidance and two-way active avoidance in response to threat of a white noise burst. Each JORT session generates a time series datafile. These time series files are fed into custom programmed scoring software. This software calculates Flight Intensity and RAI for that session
Defensive behavior: Joystick Operated Runway Task Risk Assessment Intensity
Time frame: 4 hours post-dose, Day 2 Treatment Period 1 and Day 2 Treatment period 2
The JORT uses a force sensing joystick combined with a two-dimensional runway positioned vertically on a computer monitor to measure one-way active avoidance and two-way active avoidance in response to threat of a white noise burst. Each JORT session generates a time series datafile. These time series files are fed into custom programmed scoring software. This software calculates Risk Assessment Intensity for that session
Subjective dread during Joystick Operated Runway Task (JORT)
Time frame: 4 hours post-dose, Day 2 Treatment Period 1 and Day 2 Treatment period 2
Dread rating on a scale of 1 (no threat) to 10 (maximum dread) .
Approach-avoidance learning: reward-punishment sensitivity index
Time frame: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Approach-avoidance learning: punishment sensitivity index
Time frame: 4 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Default Mode Network connectivity (fMRI)
Time frame: 7 hours post dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Reaction time to fearful faces (fMRI task)
Time frame: 7 hours post-dose, Day 2 Treatment period 1 and Day 2 Treatment period 2
Self reported State Trait Anxiety Inventory (STAI) subscale score
Time frame: 1 day post-dose, on Day 3 Treatment period 1 and Day 3 treatment period 2
The STAI sub-scale is a questionnaire that consists of 20 self-report items that assess current symptoms of anxiety, each item is rated on a four-point Likert scale from "Not at all" to "Very much so".
6 secondary outcomes
EEG power across frequency bands
Time frame: 3 and 6 hours post-dose
Plasma concentrations of endocannabinoids and ECS related biomarkers
Time frame: pre-dose to 24 hours post-dose, Day 2 to Day 3 Treatment period 1 and 2
Maximum Observed Concentration (Cmax) of SYT 510
Time frame: Up to 24 hours post-dose, Day 2 to Day3 Treatment period 1 and 2
Time of maximal plasma concentration (tmax) of SYT-510
Time frame: From dosing to follow-up visit, up to 11 weeks
Area Under the SYT-510 concentration -time Curve (AUC) from time 0 to 24 hours
Time frame: pre-dose to 24 hours post dose, on Day 2 to Day 3 Treatment periods 1 and 2
14. Incidence and severity of Treatment Emergent Adverse Events and Serious Adverse Events, changes and/or abnormalities in clinical laboratory tests, physical examination findings, vital signs, and ECGs.
Time frame: From Day 2 treatment period 1 to follow-up visit, up to 11 weeks
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jun 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Allan Young principal investigator
SLaM
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing SYT-510 in people with Generalized Anxiety Disorder, run by Synendos Therapeutics AG at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 31 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 18 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Andrea Chicca (+41783008789, andrea.chicca@synendos.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
BOLD fMRI signal in the amygdala in response to fearful stimuli (time frame: 7 hours post-dose on Day 2 Treatment period 1 and Day 2 Treatment period 2). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jun 2026.