HTLV-I-Associated MyelopathyPhase 2/3NCT01343355
Efficacy and Safety of Tamibarotene(AM80H) for HTLV-1 Associated Myelopathy/ Tropical Spastic Paraparesis (HAM/TSP)
A Phase 2/3 study testing Tamibarotene in people with HTLV-I-Associated Myelopathy, run by St. Marianna University School of Medicine at 1 site in Japan.
Trial summary
An open-label, non-randomised, uncontrolled, proof-of-concept study of patients with HTLV-I-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Participants will receive oral administration of tamibarotene in the amount of 2 mg daily over a period of 12 weeks, then 4mg daily for another 12 weeks. Read more about this study
- Who is it for?
- Ages 30 to 75 years
- Conditions the study is for
- HTLV-I-Associated Myelopathy
- What is being tested?
- Tamibarotene
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 15 participants
- Where
- 1 siteJapan
- Study dates
- Jan 2011to Oct 2011
- Phase
- Phase 2/3
- 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 30 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients who have been diagnosed as HAM according to the WHO criteria
- Patients who are positive for HTLV-I antibody in the spinal fluid
- Patients, if female, who are not pregnant or breastfeeding, either agreed to take contraceptive measures during and two years after the treatment, or sterile
- Patients, if male, who agreed to take contraceptive measures during and six months after the treatment
- Patients who have been informed and understood the contents of the study and consented to participate in the signed form.
Who cannot join
- Patients who has a rapid progress in the symptoms defined as an increase of two or more in Osame's Motor Disability Score for HAM patients in the past one year.
- Patients of hyperlipidemia (serum triglyceride higher than 400 mg/dL)
- Patients who were administered new or increased dose of corticosteroid in the past 8 weeks before the intervention
- Patients who received steroid pulse therapy in the past 8 weeks before the intervention
- Patients who were administered new or increased dose of immunosuppressant in the past 8 weeks before the intervention
- Patients with a history of serious drug allergy
- Patients with significant complication such as malignancy, severe heart failure, and other serious diseases.
- Patients who were in the past administered etretinate.
Trial locations and contacts
1 site in 1 country.
Japan1 site
Iseikai Medical Corporation, Shoyo Kashiwadai Hospital
Kanagawa, 243-0402
About this study
Official title: Open-Label, Exploratory Study of the Efficacy and Safety of Tamibarotene(AM80H) for HTLV-1 Associated Myelopathy/ Tropical Spastic Paraparesis (HAM/TSP)
An open-label, non-randomised, uncontrolled, proof-of-concept study of patients with HTLV-I-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Participants will receive oral administration of tamibarotene in the amount of 2 mg daily over a period of 12 weeks, then 4mg daily for another 12 weeks. The patients will be followed up for further 8 weeks. Efficacy will be monitored by measuring clinical scores including motor and urination function, HTLV-1 proviral load, immunological parameters, and markers in the spinal fluid. Safety will be evaluated at the same time.
- Conditions
- HTLV-I-Associated Myelopathy
- Being tested
- Tamibarotene
- Keywords
- Tropical Spastic Paraparesis, HAM, TSP
- Medical subject headings
- Paraparesis, Tropical Spastic
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
TamibaroteneDrug
Oral administration of tamibarotene 2 mg daily over a period of 12 weeks, then 4mg daily for another 12 weeks.
| Study group | Role | What they receive |
|---|---|---|
| Am80 treatment Arm | Experimental | Not described Receives: Drug: Tamibarotene |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Soluble IL-2 Receptor level in peripheral blood
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in HTLV-I viral load in peripheral blood
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in T cell population in peripheral blood
Measured: 0,12, 24, 28 and 32 weeks
Change in cerebrospinal fluid examination
Measured: baseline and after the treatment defined as from 24 to 32 weeks
Secondary outcomes (6)
Change in Osame's Motor Disability Score for HAM patients
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in The Expanded Disability Status Scale (EDSS)
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in timed 10m walk
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Manual Muscle Testing and vibratory perception of the lower limbs
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Modified Ashworth Scale
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Urination function and defecation score
Measured: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Apr 2011 (estimated)
- Study startJan 2011
- Primary completionOct 2011
- Study completionOct 2011
Why it stopped: Lack of efficacy
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HTLV-I-Associated MyelopathyStudies 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 2/3
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Enrolment
- 15 participants (actual)
Sponsor and investigators
- Lead sponsor
- St. Marianna University School of Medicine
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Yoshihisa Yamano, St. Marianna University School of Medicine
- Investigators
- Yoshihisa Yamano, MD, Principal investigator, St. Marianna University School of Medicine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01343355
- Sponsor's protocol ID
- AM80H-01
- Status last verified
- Oct 2026
- First submitted
- 25 Apr 2011
- Last updated
- 8 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
Study at a glance
From the registry record, last updated by the sponsor on 8 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Open-Label, Exploratory Study of the Efficacy and Safety of Tamibarotene(AM80H) for HTLV-1 Associated Myelopathy/ Tropical Spastic Paraparesis (HAM/TSP)
- ClinicalTrials.gov ID
- NCT01343355
- Acronym / sponsor ID
- AM80H-01
- Conditions
- HTLV-I-Associated Myelopathy
- Keywords
- Tropical Spastic Paraparesis, HAM, TSP
- Phase
- Phase 2/3
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Lack of efficacy
- Enrolment
- 15 participants (actual)
- Lead sponsor
- St. Marianna University School of MedicineUniversity, hospital or other
- Study start
- Jan 2011 (actual)
- Primary completion
- Oct 2011 (actual)
- Study completion
- Oct 2011 (actual)
- First posted
- 28 Apr 2011 (estimated)
- 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.
An open-label, non-randomised, uncontrolled, proof-of-concept study of patients with HTLV-I-associated myelopathy/Tropical Spastic Paraparesis (HAM/TSP). Participants will receive oral administration of tamibarotene in the amount of 2 mg daily over a period of 12 weeks, then 4mg daily for another 12 weeks. The patients will be followed up for further 8 weeks. Efficacy will be monitored by measuring clinical scores including motor and urination function, HTLV-1 proviral load, immunological parameters, and markers in the spinal fluid. Safety will be evaluated at the same time.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Am80 treatment Arm | Experimental | Drug: Tamibarotene |
Who may qualify
- Ages
- 30 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Patients who have been diagnosed as HAM according to the WHO criteria
- Patients who are positive for HTLV-I antibody in the spinal fluid
- Patients, if female, who are not pregnant or breastfeeding, either agreed to take contraceptive measures during and two years after the treatment, or sterile
- Patients, if male, who agreed to take contraceptive measures during and six months after the treatment
- Patients who have been informed and understood the contents of the study and consented to participate in the signed form.
Key exclusion criteria (8 listed)
- Patients who has a rapid progress in the symptoms defined as an increase of two or more in Osame's Motor Disability Score for HAM patients in the past one year.
- Patients of hyperlipidemia (serum triglyceride higher than 400 mg/dL)
- Patients who were administered new or increased dose of corticosteroid in the past 8 weeks before the intervention
- Patients who received steroid pulse therapy in the past 8 weeks before the intervention
- Patients who were administered new or increased dose of immunosuppressant in the past 8 weeks before the intervention
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 |
|---|---|---|
| TamibaroteneOral administration of tamibarotene 2 mg daily over a period of 12 weeks, then 4mg daily for another 12 weeks. | Drug | Am80 treatment Arm |
Primary outcome
Change in Soluble IL-2 Receptor level in peripheral blood
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in HTLV-I viral load in peripheral blood
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in T cell population in peripheral blood
Time frame: 0,12, 24, 28 and 32 weeks
Change in cerebrospinal fluid examination
Time frame: baseline and after the treatment defined as from 24 to 32 weeks
6 secondary outcomes
Change in Osame's Motor Disability Score for HAM patients
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in The Expanded Disability Status Scale (EDSS)
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in timed 10m walk
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Manual Muscle Testing and vibratory perception of the lower limbs
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Modified Ashworth Scale
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Change in Urination function and defecation score
Time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks
Results and safety
The study was stopped early (reason given: Lack of efficacy). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 8 Oct 2026.
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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.
Yoshihisa Yamano, MD principal investigator
St. Marianna University School of Medicine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2/3 study testing Tamibarotene in people with HTLV-I-Associated Myelopathy, run by St. Marianna University School of Medicine at 1 site in Japan.
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 5 inclusion and 8 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 8 Oct 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 Japan. 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 combined 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.
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
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: Lack of efficacy). 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?
Change in Soluble IL-2 Receptor level in peripheral blood (time frame: 0, 4, 8, 12, 16, 20, 24, 28 and 32 weeks). The study lists 4 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 8 Oct 2026.