Healthy VolunteersPhase 1NCT07329621
A Brain Imaging Study to Assess the Binding of MSP-2020 to Serotonin 5-HT2A Receptors in Healthy Male Adults
A Phase 1 study testing MSP-2020 in people with Healthy Volunteers, run by Otsuka Pharmaceutical Development & Commercialization, Inc. at 1 site in United Kingdom.
Trial summary
This study is to see how well MSP-2020 attaches to specific targets in the brain called serotonin type 2A receptors (5-HT2AR). This study will also look at how much of the study drug (and its metabolite) is in the blood and how long the study drug stays in the blood, as well as the safety of MSP 2020. Read more about this study
- Who is it for?
- Ages 23 to 55 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Healthy Volunteers
- What is being tested?
- MSP-2020
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 8 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 15 Jan 2026to 17 Jul 2026
- Phase
- Phase 1
- Are there results?
- None posted in the registry
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 23 to 55 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Able to stay in the CRU for up to 4 days.
- Body mass index (BMI) between 18.0 to 32.0 kg/m2 (inclusive).
- In good health as determined by: a. Medical history; b. Physical and neurological examination; c. Concomitant medications; d. ECG; e. Screening echocardiogram; f. Serum chemistry, urinalysis, haematology, coagulation, and serology (HIV screen, HBsAg, and anti-HCV) tests.
Who cannot join
- In first-degree relatives, a history of any schizophrenia-spectrum disorder, psychotic disorder, or bipolar and related disorders.
- History of allergy to tracer [11C]CIMBI-36.
- MRI incompatibility due to implants including but not limited to pacemaker, artificial joints, or non-removable body piercings, and/or other contraindications for MRI such as claustrophobia, metal objects/fragments, or fragments in the head or body that would present a risk during the MRI scanning procedure, or have worked with ferrous metals (eg, welding), or have motor problems that prevent the participant from lying still for the MRI.
- Pathological MRI findings that would preclude from trial participation.
- History of prior radiation exposure for research purposes such that participation in this trial would result in an ionising radiation exposure of > 10 mSv within a year (12 months) of the first PET scan that would cause the participant to exceed the yearly dose limit.
- Have a negative modified Allen test at screening.
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- Contraindications to radial arterial cannula (including but not limited to cellulitis or other infections over the radial artery, absence of palpable radial artery pulse, or a clinically significant abnormal coagulation profile).
- Clinically significant abnormality in past medical history, or at the screening physical examination, that in the investigator's or sponsor's opinion may place the participant at risk or interfere with outcome variables including absorption, distribution, metabolism, and excretion of drug. This includes, but is not limited to, history of or concurrent cardiac, hepatic, renal, neurologic, endocrine, gastrointestinal, respiratory, haematologic, dermatologic, and immunologic disease.
- History of alcohol and/or substance use disorder within the last 24 months according to the Diagnostic Statistical Manual of Mental Disorders and in past medical history or in the investigator's opinion, or intake of > 21 units of alcohol weekly, and the inability to refrain from alcohol use from 48 hours before screening and within 72 hours prior to dosing until discharge from the CRU on Day 2. One unit is equivalent to 1 (25 mL) measure of 40% spirits. For reference, one 330 mL bottle of 5% beer contains 1.7 units and a standard (175 mL) glass of 12% wine contains 2.1 units.
- Note: Other protocol-specified Inclusion/Exclusion criteria may apply.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Phase 1, Open-label, Positron Emission Tomography (PET) Trial to Measure Serotonin 5-HT2A Receptor Occupancy Following Single Oral Doses of MSP-2020 in Healthy Male Adults
This study is to see how well MSP-2020 attaches to specific targets in the brain called serotonin type 2A receptors (5-HT2AR). This study will also look at how much of the study drug (and its metabolite) is in the blood and how long the study drug stays in the blood, as well as the safety of MSP 2020.
- Conditions
- Healthy Volunteers
- Being tested
- MSP-2020
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MSP-2020Drug
capsule
| Study group | Role | What they receive |
|---|---|---|
| MSP-2020 Oral Administration | Experimental | Participants will receive a single dose of MSP-2020 on Day 1. Receives: Drug: MSP-2020 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percent Change in Specific Binding of [11C]CIMBI-36 from Baseline and EC50 Using Cortical Regions [11C]CIMBI-36 BPND
Measured: Up to Day 2
PK Plasma Concentration of MSP-2020 and its Metabolite
Measured: Up to Day 2
Maximum (peak) Plasma Concentration of MSP-2020 and its Metabolite
Measured: Up to Day 2
Time to Maximum (peak) Plasma Concentration of MSP-2020 and its Metabolite
Measured: Up to Day 2
Half-life (t1/2) of MSP-2020 and its metabolite
Measured: Up to Day 2
Area under the concentration-time curve (AUCt) of MSP-2020 and its metabolite
Measured: Up to Day 2
Secondary outcomes (8)
Change from baseline in relevant scales
Measured: Up to Day 2
Concentration of the metabolite at which 50% of the 5-HT2A receptors are occupied, as measured by PET imaging
Measured: Up to Day 2
Number of Participants With Adverse Events (AEs)
Measured: Up to Day 15
Number of Participants With Potentially Clinically Significant Changes in Vital Signs
Measured: Up to Day 2
Number of Participants With Potentially Clinically Significant Changes in Electrocardiogram (ECG)
Measured: Up to Day 2
Number of Participants With Potentially Clinically Significant Changes in Laboratory Tests
Measured: Up to Day 15
Number of Participants With Potentially Clinically Significant Changes in Physical and Neurological Examinations
Measured: Up to Day 15
Number of Participants With Suicidality on Columbia-Suicide Severity Rating Scale (C-SSRS)
Measured: Up to Day 15
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Jan 2026
- Study start15 Jan 2026
- Primary completion10 Jul 2026
- Study completion17 Jul 2026
Why it stopped: The study was terminated due to operational and scientific constraints. The termination was not based on safety concerns.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Healthy VolunteersStudies of the same condition, open and under way.
- More trials run by Otsuka Pharmaceutical Development & Commercialization, Inc.The sponsor's other registered studies.
- 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 1
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 8 participants (actual)
Sponsor and investigators
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07329621
- Sponsor's protocol ID
- 358-201-00002
- Status last verified
- Aug 2026
- First submitted
- 19 Dec 2025
- Last updated
- 18 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: Anonymized individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.
Study at a glance
From the registry record, last updated by the sponsor on 18 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1, Open-label, Positron Emission Tomography (PET) Trial to Measure Serotonin 5-HT2A Receptor Occupancy Following Single Oral Doses of MSP-2020 in Healthy Male Adults
- ClinicalTrials.gov ID
- NCT07329621
- Acronym / sponsor ID
- 358-201-00002
- Conditions
- Healthy Volunteers
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: The study was terminated due to operational and scientific constraints. The termination was not based on safety concerns.
- Enrolment
- 8 participants (actual)
- Lead sponsor
- Otsuka Pharmaceutical Development & Commercialization, Inc.Industry (pharma, biotech, devices)
- Study start
- 15 Jan 2026 (actual)
- Primary completion
- 10 Jul 2026 (actual)
- Study completion
- 17 Jul 2026 (actual)
- First posted
- 9 Jan 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 study is to see how well MSP-2020 attaches to specific targets in the brain called serotonin type 2A receptors (5-HT2AR). This study will also look at how much of the study drug (and its metabolite) is in the blood and how long the study drug stays in the blood, as well as the safety of MSP 2020.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| MSP-2020 Oral Administration | Experimental | Drug: MSP-2020Participants will receive a single dose of MSP-2020 on Day 1. |
Who may qualify
- Ages
- 23 to 55 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Able to stay in the CRU for up to 4 days.
- Body mass index (BMI) between 18.0 to 32.0 kg/m2 (inclusive).
- In good health as determined by: a. Medical history; b. Physical and neurological examination; c. Concomitant medications; d. ECG; e. Screening echocardiogram; f. Serum chemistry, urinalysis, haematology, coagulation, and serology (HIV screen, HBsAg, and anti-HCV) tests.
Key exclusion criteria (10 listed)
- In first-degree relatives, a history of any schizophrenia-spectrum disorder, psychotic disorder, or bipolar and related disorders.
- History of allergy to tracer [11C]CIMBI-36.
- MRI incompatibility due to implants including but not limited to pacemaker, artificial joints, or non-removable body piercings, and/or other contraindications for MRI such as claustrophobia, metal objects/fragments, or fragments in the head or body that would present a risk during the MRI scanning procedure, or have worked with ferrous metals (eg, welding), or have motor problems that prevent the participant from lying still for the MRI.
- Pathological MRI findings that would preclude from trial participation.
- History of prior radiation exposure for research purposes such that participation in this trial would result in an ionising radiation exposure of > 10 mSv within a year (12 months) of the first PET scan that would cause the participant to exceed the yearly dose limit.
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 |
|---|---|---|
| MSP-2020capsule | Drug | MSP-2020 Oral Administration |
Primary outcome
Percent Change in Specific Binding of [11C]CIMBI-36 from Baseline and EC50 Using Cortical Regions [11C]CIMBI-36 BPND
Time frame: Up to Day 2
PK Plasma Concentration of MSP-2020 and its Metabolite
Time frame: Up to Day 2
Maximum (peak) Plasma Concentration of MSP-2020 and its Metabolite
Time frame: Up to Day 2
Time to Maximum (peak) Plasma Concentration of MSP-2020 and its Metabolite
Time frame: Up to Day 2
Half-life (t1/2) of MSP-2020 and its metabolite
Time frame: Up to Day 2
Area under the concentration-time curve (AUCt) of MSP-2020 and its metabolite
Time frame: Up to Day 2
8 secondary outcomes
Change from baseline in relevant scales
Time frame: Up to Day 2
Concentration of the metabolite at which 50% of the 5-HT2A receptors are occupied, as measured by PET imaging
Time frame: Up to Day 2
Number of Participants With Adverse Events (AEs)
Time frame: Up to Day 15
Number of Participants With Potentially Clinically Significant Changes in Vital Signs
Time frame: Up to Day 2
Number of Participants With Potentially Clinically Significant Changes in Electrocardiogram (ECG)
Time frame: Up to Day 2
Number of Participants With Potentially Clinically Significant Changes in Laboratory Tests
Time frame: Up to Day 15
Number of Participants With Potentially Clinically Significant Changes in Physical and Neurological Examinations
Time frame: Up to Day 15
Number of Participants With Suicidality on Columbia-Suicide Severity Rating Scale (C-SSRS)
Time frame: Up to Day 15
Results and safety
The study was stopped early (reason given: The study was terminated due to operational and scientific constraints. The termination was not based on safety concerns.). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Aug 2026.
- Otsuka Clinical Trial WebsiteLink provided by the sponsor.
- Otsuka Clinical Trial TransparencyLink provided by the sponsor.
- Individual participant dataSharing planned: No. Anonymized individual participant data (IPD) that underlie the results of this study will be shared with researchers to achieve aims pre-specified in a methodologically sound research proposal. Small studies with less than 25 participants are excluded from data sharing.
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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. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing MSP-2020 in people with Healthy Volunteers, run by Otsuka Pharmaceutical Development & Commercialization, Inc. 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 3 inclusion and 10 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: stopped early, as of the sponsor's last update on 18 Aug 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. 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 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study was stopped early (reason given: The study was terminated due to operational and scientific constraints. The termination was not based on safety concerns.). Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Percent Change in Specific Binding of [11C]CIMBI-36 from Baseline and EC50 Using Cortical Regions [11C]CIMBI-36 BPND (time frame: Up to Day 2). The study lists 6 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 Aug 2026.