Skip to content

Targeted Alpha Therapy Using Astatine (At-211) Against Differentiated Thyroid Cancer

Phase I Investigator-initiated Clinical Trial in Patients With Differentiated Thyroid Cancer (Papillary Cancer, Follicular Cancer) by the Targeted Alpha Therapy Drug TAH-1005 ([211At] NaAt) (Alpha-T1 Study)

Status
Completed
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05275946
Enrollment
11
Registered
2022-03-11
Start date
2021-11-20
Completion date
2025-03-31
Last updated
2025-04-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Thyroid Cancer

Keywords

Targeted alpha therapy, Astatine (At-211)

Brief summary

Single intravenous administration of TAH-1005 is performed in patients with differentiated thyroid cancer (papillary cancer, follicular cancer) who cannot obtain therapeutic effect with standard treatment or who have difficulty in implementing and continuing standard treatment. The safety, pharmacokinetics, absorbed dose, and efficacy will be evaluated to determine the recommended dose for Phase II clinical trial.

Detailed description

Radioactive iodine (I-131) has long been used clinically for patients with metastatic differentiated thyroid cancer. However, some patients are refractory to repetitive I-131 treatment, despite the targeted regions showing sufficient iodine uptake. In such patients, beta-particle therapy using I-131 is inadequate and another strategy is needed using more effective radionuclide targeting the sodium/iodide symporter (NIS). Astatine (At-211) is receiving increasing attention as an alpha-emitter for targeted radionuclide therapy. At-211 is a halogen element with similar chemical properties to iodine. Alpha particles emitted from At-211 has higher linear energy transfer as compared to beta particles from I-131 and exert a better therapeutic effect by inducing DNA double strand breaks and free radical formation. Thus, targeted alpha therapy using At-211 is highly promising for the treatment of advanced differentiated thyroid cancer.

Interventions

DRUGTargeted alpha therapy

Single intravenous administration

Sponsors

Osaka University
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
No minimum to 18 Years
Healthy volunteers
No

Inclusion criteria

1. Patients with differentiated thyroid cancer (papillary cancer, follicular cancer) after total thyroidectomy who meet the following conditions (1) resistance to standard treatment or (2) difficulty in continuing standard treatment (1) Patients who are refractory to standard treatment such as 131I-NaI treatment Insufficient therapeutic effect after 3 or more 131I-NaI treatments. 131I-NaI treatment resistance and difficulty in performing or continuing tyrosine kinase inhibitor (TKI) treatment (2) Patients who have difficulty continuing standard treatment such as 131I-NaI treatment Ablation for residual thyroid or 131I-NaI treatment for relapsed / metastatic lesions has been performed, but relapsed / metastatic lesions were observed at the time of participation in this study, and 131I-NaI is the standard treatment. If it is difficult to continue treatment or if local radiation therapy (including addition) is not indicated (if it is not 131I-NaI treatment resistant, TKI treatment is not indicated). 2. Patients aged 18 years or older at the time of consent acquisition 3. Patients with stable general condition with PS (Performance status) of 0 to 2 in ECOG (Eastern Cooperative Oncology Group) 4. Patients who can be expected to survive for 6 months or more, judging from clinical symptoms and medical examination findings 5. Patients with no or controlled brain metastases with symptoms 6. Patients with no clinically significant abnormal findings in electrocardiogram, respiratory rate, and blood oxygen saturation within 30 days before registration 7. Patients whose laboratory values within 30days before the enrollment are within the range specified in the protocol 8. Patients who thoroughly listened to the explanation of the clinical trial, agreed to the examination, visit during the observation period and follow-up survey, contraception during the clinical trial period, etc. according to the clinical trial protocol, and signed the consent document.

Exclusion criteria

1. Patients who need fertility preservation 2. Pregnant or potentially pregnant women, lactating patients 3. Patients with active double cancer (simultaneous double cancer and ectopic double cancer with a disease-free period of 5 years or less) 4. Patients who received other investigational or unapproved drugs within 5 weeks prior to enrollment 5. Patients who received chemotherapy, immunotherapy or radiation therapy within 8 weeks prior to enrollment in this study 6. Patients with uncontrollable active infections 7. HBsAg positive, HCV antibody positive or HIV antibody positive patients 8. Patients with mental illness or psychiatric symptoms who are judged to be difficult to participate in clinical trials 9. Other patients who are judged to be inappropriate by the investigator, etc.

Design outcomes

Primary

MeasureTime frameDescription
Treatment-related adverse events as assessed by CTCAE v5.0From the start of iodine restriction to 6 months after administrationType, severity, frequency of occurrence and duration of adverse events
Dose Limiting Toxicitywithin 4 weeks after administrationToxicity is defined as one or more of the following items for which a causal relationship with the investigational drug cannot be ruled out. 1. Grade 3 \* hematological toxicity that lasts for 7 days or more 2. Hematological toxicity of Grade 4 \* or higher regardless of duration 3. Febrile neutropenia regardless of duration 4. Thrombocytopenia with bleeding tendency or requiring platelet transfusion 5. Anemia requiring red blood cell transfusion 6. Neutropenia with infection 7. Non-hematological toxicity of Grade 3 \* or higher that does not improve with symptomatic treatment and lasts for 7 days or longer. However, the following are excluded. * Abnormal laboratory test values that are not clinically significant * Toxicity that can be controlled to Grade 2 \* or less with maximum supportive care * Due to exacerbation of the underlying disease (\*: Grade specified in CTCAE v.5.0J COG version)

Secondary

MeasureTime frameDescription
Symptoms and examination findingswithin 4 weeks after administrationSubjective symptoms and medical examination findings
Hematological examinationwithin 4 weeks after administrationWhite blood cell count (/μL), red blood cell count (×10\^4/μL), hemoglobin (g/dL), hematocrit (%), platelet count (×10\^4/μL)
Blood pressurewithin 4 weeks after administrationSystolic and diastolic blood pressure (mmHg)
Heart ratewithin 4 weeks after administrationPulse (bpm)
Blood oxygen saturationwithin 4 weeks after administrationPercutaneous oxygen saturation (%)
Respiratory ratewithin 4 weeks after administrationRespiratory rate (times/min)
Blood biochemical testwithin 4 weeks after administrationTotal protein (g/dL), albumin (g/dL), total bilirubin (mg/dL), AST (U/L), ALT (U/L), ALP (U/L), γ-GTP (U/L), LDH (U/L), total cholesterol (mg/dL), triglyceride (mg/dL), uric acid (mg/dL), BUN (mg/dL), creatinine (mg/dL), CK (U/L), Na (mmol/L), K (mmol/L), Cl (mmol/L), Ca (mmol/L), CRP (mg/dL)
Urinalysiswithin 4 weeks after administrationUrinary protein, urine sugar, urineous blood, urobilinogen (qualitative test)
12-lead ECGwithin 4 weeks after administrationPresence or absence of abnormal findings in waveform
Pharmacokinetic parameters 1)until 24 hours after administrationAUC (Area under the plasma concentration versus time curve, Bq·min/mL)
Pharmacokinetic parameters 2)until 24 hours after administrationAUC / D (Area under the plasma concentration versus time curve divided by injected dose, min/mL)
Pharmacokinetic parameters 3)until 24 hours after administrationCmax (Peak plasma concentration, Bq/mL)
Pharmacokinetic parameters 4)until 24 hours after administrationCmax / D (Peak plasma concentration divided by injected dose, /mL)
Body temperaturewithin 4 weeks after administrationBody temperature (°C)
Pharmacokinetic parameters 6)until 24 hours after administrationT1 / 2 (Time from Tmax to half of maximum plasma concentration, min)
Pharmacokinetic parameters 7)until 24 hours after administrationCL (Clearance, L/hr/kg)
Pharmacokinetic parameters 8)until 24 hours after administrationVss (Volume of distribution in steady state, L/kg)
Excretion 1) urinaryuntil 24 hours after administrationUrine volume (mL) and radioactivity (Bq): Radioactivity and volume will be combined to report radioactivity concentration (Bq/mL).
Excretion 2) fecaluntil 24 hours after administrationStool weight (g) and radioactivity (Bq): Radioactivity and weight will be combined to report radioactivity concentration (Bq/g).
Excretion 3) exhaleduntil 24 hours after administrationExhaled volume (mL) and radioactivity (Bq): Radioactivity and volume will be combined to report radioactivity concentration (Bq/mL).
Radioactivity concentration in major organsuntil 24 hours after administrationChanges in radioactivity concentration (Bq/mL) in major organs over time: Whole-body imaging (planar and SPECT/CT) is performed to evaluate the distribution in the body at 1 hour, 3 hours, 24 hours after the administration.
Residence time of major organsuntil 24 hours after administrationResidence time (hr) of each organ
Absorbed dose of major organsuntil 24 hours after administrationAbsorbed dose (mGy / MBq) of each organ
Preliminary effectiveness assessment 1)3 and 6 months after administrationEvaluation of treatment effect on CT images by referring to the Revised RECIST guideline (version 1.1): CR (Complete response), PR (Partial response), SD (Stable disease), or PD (Progressive disease)
Preliminary effectiveness assessment 2)3 and 6 months after administrationEvaluation of uptake change in diagnostic \[131I\] NaI scans: CR , PR, SD, or PD
Preliminary effectiveness assessment 3)3 and 6 months after administrationEvaluation of changes in tumor markers: blood thyroglobulin (ng/mL)
Pharmacokinetic parameters 5)until 24 hours after administrationTmax (Time to maximum plasma concentration, min)
Body weightwithin 4 weeks after administrationWeight (kg)

Countries

Japan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026