CClinicalTrials.gg
Sign In
CompletedNCT04105543Updated Sep 2, 2025Results posted

CLR 131 Combined With Radiation for Head and Neck Cancer

A Phase 1 interventional study of CLR 131 in Head and Neck Cancer, sponsored by University of Wisconsin, Madison. Completed at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-09-02.

Sponsored by University of Wisconsin, Madison · Phase 1, Interventional, and Treatment

Phase
Phase 1
Study type
Interventional
Enrollment
12
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Study summary

This is a Phase 1 study of the use of an investigational drug that selectively delivers radiation to malignant tumor cells, CLR 131, in combination with external beam radiation therapy (EBRT) in subjects with locoregionally recurrent head and neck cancer. The trial will enroll up to 12 participants who are amenable to retreatment with radiation therapy. Participants who also have distant metastatic disease may be enrolled on this clinical trial, but they must have evaluable disease that will be clinically treated with radiation therapy, as per standard of care. All participants will receive a dosimetry test dose of CLR 131 to establish drug uptake by the tumor and enable Monte Carlo dose estimation based on CLR 131 SPECT/CT imaging evaluation. Participants showing uptake will receive a cumulative tumor dose of 60-70 Gy using personalized dose calculation (via Monte Carlo methods) of CLR 131 combined with external beam radiation.

Read the detailed description

Following informed consent, all participants will receive a dosimetry test dose of 15 mCi CLR 131 to establish drug uptake by the tumor and enable Monte Carlo dose estimation based on CLR 131 SPECT/CT imaging evaluation.

Participants who have uptake of the CLR 131 dosimetry test dose at their disease site as determined by the study radiologist will be eligible to participate on the treatment portion of this clinical trial. Participants showing uptake will receive a cumulative tumor dose of 60-70 Gy using personalized dose calculation of CLR 131 (via Monte Carlo) combined with external beam radiation. In this study, we are also studying a subset of up to 6 patients who do not uptake after the CLR 131 test dose, who will still proceed with treatment with CLR 131.

This clinical trial involves two cohorts of subjects: (a) dose escalation and (b) dose expansion. In the dose escalation phase, an mTPI-2 design, an extension of modified toxicity probability interval (mTPI-2), will be used to identify the maximum tolerated dose (MTD) using cohorts of 4 participants and up to 3 dose levels of CLR 131. Participants in the dose escalation phase will receive 2 doses of CLR 131 with the first dose on day 1 followed by the second dose on day 8.

Treatment with CLR 131 on the dose escalation cohort will begin at dose level 1 (15.6 mCi/m2). Participants at dose level 1 will receive an intravenous infusion of CLR 131 at 15.6 mCi/m2 on day 1 followed by a second dose on day 8. Participants at dose level 2 will receive an intravenous infusion of CLR 131 at 18.75 mCi/m2 on day 1 followed by a second dose on day 8.

Once the MTD is determined by the dose escalation phase, participants will be enrolled on the dose expansion cohort. Participants on the dose expansion cohort will receive 2 doses of CLR 131 with the first dose on day 1 followed by the second dose on day 8, with the dose determined by the dose escalation phase.

SPECT/CT imaging will be performed on days 2, 3, 4-6, and 7-8 of the treatment period to visualize and quantitate the biodistribution of CLR 131. Based on these SPECT/CT imaging scans, the Bednarz lab will utilize the Monte Carlo method to predict absorbed dose of CLR 131 to tumors and normal structures.

All participants will start thyroid-protection medication the day prior to the CLR 131 dosimetry test dose and will continue to take thyroid protection medication for 14 days after the last CLR 131 dose.

Based on the calculated absorbed dose of CLR 131 to the specific targeted tissue, the participant will undergo external beam radiation therapy (EBRT) to complete the designated radiation dose outlined in the re-irradiation plan, as per standard of care. Prior to CLR 131 administration and at 3 and 6 months post EBRT, participants will be assessed for changes to swallow function. Prior to CLR 131 administration and at 3, 6 and 12 months post EBRT, quality of life measures and salivary characteristics will be assessed. The investigators anticipate the total study (baseline, CLR 131 administration, EBRT and 3, 6, 12 and 24 month follow up assessments) to take 27 months per participant.

02

Conditions studied

  • Head and Neck Cancer
03

In context

Head and Neck Neoplasms

2,344 studies on the registry are indexed under Head and Neck Neoplasms; 551 are open to participants now.

This study's enrollment of 12 is below the median of 47 across 1,751 interventional studies indexed under Head and Neck Neoplasms.

Browse Head and Neck Neoplasms studies →

Lead sponsor

University of Wisconsin, Madison is the lead sponsor of 1,161 studies on the registry; 182 are open to participants now.

Of its 151 completed or terminated interventional studies of FDA-regulated products, 114 (75%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Participant must be informed of the investigational nature of the study and must be able to sign a written informed consent.
  • Participants with histologically or cytologically confirmed solid malignancy that has recurred in the head and neck (above the clavicles) region, e.g., participants with recurrent cutaneous squamous cell carcinoma, salivary gland tumors or esthesioneuroblastoma are eligible for this clinical trial.
  • Participants must have undergone previous curative intent therapy, with radiation as a primary or adjuvant therapy.
  • Participants may have distant metastatic disease, as long as the locoregional site of recurrence is deemed eligible for radiation therapy, and treatment of the loco-regional disease is deemed as taking precedence over treatment of the remaining systemic disease.
  • Participants must have at least one evaluable (measurable or non-measurable) recurrent lesion that is amenable to radiation therapy.
  • Participants must demonstrate uptake of CLR 131 via SPECT/CT imaging, as determined by the study radiologist, in the specified site of recurrent/metastatic disease that is to be treated with radiation therapy. There is a subset of up to 6 patients who may continue with CLR 131 treatment without uptake on the SPECT/CT scan after the test dose.
  • Participants must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 1.
  • Participants must have a life expectancy of at least 6 months.

  • The participant has adequate hematologic function, as evidenced by:

    • an absolute neutrophil count (ANC) ≥ 1500 / µL
    • hemoglobin ≥9 g/dL (5.58 mmol/L)

    • and platelets ≥100,000 / µL

      • If full-dose anticoagulation therapy is used, platelets ≥ 150,000 / µL are required.

        • If participant is on full-dose anticoagulation therapy, the anticoagulation therapy must be reversible, and reversal of the anticoagulation therapy must not be life-threatening, as judged by the investigator.

  • The participant has adequate renal function as defined by:

    • serum creatinine ≤ 1.5 times the upper limit of normal (ULN) or Cockcroft-Gault calculated creatinine clearance >/= 60 ml/min

  • The participant has adequate hepatic function as defined by:

    • total bilirubin ≤ 1.5 mg/dL (25.65 μmol/L)
    • aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 3.0 times the ULN
  • Women of childbearing potential (WOCP) have a confirmed negative urine pregnancy test within 24 hours prior to test dose of CLR 131.
  • Participants must use a medically acceptable method of birth control such as an oral, implantable, injectable, or transdermal hormonal contraceptive, an intrauterine device (IUD), a double barrier method (condoms, sponge, diaphragm, or vaginal ring with spermicidal jellies or cream), or total abstinence during the study participation and for 6 months after last dose of study drug. Women who are postmenopausal for at least 1 year or surgically sterile (bilateral tubal ligation, bilateral oophorectomy, or hysterectomy) are not considered to be WOCP.
  • Men who are not surgically or medically sterile agree to use an acceptable method of contraception. Male participants with female sexual partners who are pregnant, possibly pregnant, or who could become pregnant during the study must abstain from intercourse for three weeks after each CLR 131 dose and agree to use condoms at least 6 months after the last dose of study drug. Total abstinence for the same study period is an acceptable alternative.

Exclusion criteria

Exclusion Criteria:

  • Recurrent tumor recommended for surgical resection based on multidisciplinary Head and Neck Oncology Tumor Board Review
  • Thyroid cancer
  • Known hypersensitivity to iodine
  • Other concurrent severe and/or uncontrolled concomitant medical or psychiatric conditions (e.g. active or uncontrolled infection, uncontrolled diabetes) that could cause unacceptable safety risks or compromise compliance with the protocol, per investigator discretion
  • Chemotherapy or major surgery within 4 weeks, or radiotherapy within 2 weeks prior to test dose of CLR 131.
  • Participants with clinically significant adverse events due to agents administered more than 4 weeks prior to test dose of CLR 131 (alopecia and fatigue excluded). Clinical significance to be determined by investigator.
  • The participant is pregnant, breastfeeding, or expecting to conceive or father children within the projected duration of the trial, starting with the screening visit through 6 months after the last dose of trial treatment.
  • Any ongoing or active infection, including active tuberculosis, hepatitis B or C, or known infection with the human immunodeficiency virus (HIV)
  • Concurrent treatment with any other anti-cancer or investigational agents. Participants cannot be receiving concomitant chemotherapy, radiotherapy, experimental therapy or any other therapy not otherwise outlined by the trial for the purposes of anti-cancer treatment.
  • Participants with a history of or concurrent second primary malignancy (stage III or IV) within 5 years to study enrollment are excluded.
  • Participants with a history of prior invasive malignancy (except early-stage I or II non-melanomatous skin cancer, carcinoma in situ of the breast, cervical carcinoma in situ, stage I-II papillary thyroid cancer, or low or very low-risk prostate cancer which has been completely treated with surgery or radiation) treated within 2 years of study enrollment are excluded.
  • Participants that have had total body or hemibody irradiation, or have had prior systemic radioisotope therapy (except for benign thyroid disease)
  • Poor venous access and will be unable to receive study drug into a peripheral venous catheter.
  • Significant traumatic injury within 6 weeks prior to enrollment
  • Extradural tumor in contact with the spinal cord or tumor located where swelling in response to therapy may impinge upon the spinal cord
  • Any history of cerebrovascular accident (CVA) or transient ischemic attack within 12 months prior to study entry
  • History of myocardial infarction, ventricular arrhythmia, stable/unstable angina, symptomatic congestive heart failure, coronary/peripheral artery bypass graft or stenting or other significant cardiac disease within 6 months prior to study entry
  • QT interval corrected for heart rate using Fridericia's formula (QTcF) ≥480 ms.
  • Any condition requiring the use of immunosuppression, excluding rheumatologic conditions treated with stable doses of corticosteroids (equivalent to £ prednisone 10 mg daily)
  • Ongoing hemodialysis or peritoneal dialysis
  • Poorly controlled severe Chronic Obstructive Pulmonary Disease (COPD)
  • Uncontrolled hypothyroidism or hyperthyroidism
  • Any medical condition that predisposes the subject to uncontrolled bleeding such as hemophilia, factor deficiencies, severe liver disease, or von Willebrand disease.
05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
12 participants (actual)

Study arms

  • Experimental
    CLR 131 Dose Escalation

    Enrollment will start at dose level 1 (first 4 participants). Participants will receive 2 doses of CLR 131 intravenously with the first dose on day 1 followed by the second dose on day 8. Dose Level -1 (de-escalation dose, if toxicities warrant) = 12.5 mCi/m\^2 Dose Level 1 (beginning dose) = 15.6 mCi/m\^2 Dose Level 2 (escalation dose) = 18.75 mCi/m\^2 Dose escalation will proceed with no limiting toxicities at each level (maximum of 8 participants at each dose level). With maximum tolerated dose confirmed, an expansion phase will proceed.

    Drug: CLR 131

Interventions

  • DrugCLR 131

    CLR 131 is a radiopharmaceutical dosed intravenously over a period of approximately 30 minutes, dose will be based on total body surface area calculated from actual body weight and height

    Also known as: I-131-CLR1404

06

What researchers measure

Primary outcomes

  1. Incidence of Treatment Related Adverse Events

    Incidence of adverse events assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Adverse Events Grading (1 = mild, 2 = moderate, 3 = severe, 4 = life threatening, and 5 = death)

    Time frame: up to 18 weeks

  2. Summary of Adverse Events Possibly Related to Treatment

    Adverse Events Grading (1 = mild, 2 = moderate, 3 = severe, 4 = life threatening, and 5 = death)

    Time frame: up to 18 weeks

Secondary outcomes

  1. CLR 131 Tumor Uptake Via SPECT/CT Imaging

    Investigators will use SPECT/CT imaging scans to predict the adsorbed dose of CLR 131 to tumors with the Monte Carlo method.

    Time frame: Up to 8 days

  2. Median Radiation Treatment Time

    Time frame: up to 14 weeks

  3. Number of Dose Delays

    Time frame: up to 14 weeks

  4. Response Rates

    Complete response (CR), disappearance of all tumors; Partial response (PR), at least 30% decrease in the sum of the longest diameter of target tumors; Stable disease (SD), no increase or decrease to tumor size; Progressive disease (PD), increasing tumor size. RECIST v1.1, Response Evaluation Criteria in Solid Tumors version 1.

    Time frame: 6 months post completion of EBRT, up to 9 months on study

  5. Overall Response Rate (ORR)

    ORR defined as the proportion of subjects who experience either a partial response or complete response within 6 months post completion of EBRT as measured by standard of care imaging (e.g. CT, MR, PET-MR).

    Time frame: 6 months post completion of EBRT, up to 9 months on study

  6. Swallow Function: DIGEST Scale

    Swallow function assessed by Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale before and after treatment. The DIGEST scale cross references a clinician determined 'safety' grade with an 'efficiency' grade for an overall score between 0-4 where 0 is asymptomatic and 4 is life threatening. Data collected at baseline, 3 months, and 6 months post completion of external beam radiation therapy (EBRT).

    Time frame: up to 6 months post completion of EBRT (up to 9 months on study)

  7. Quality of Life: MDADI Score

    Quality of life assessed by MD Anderson Dysphagia Inventory score (MDADI) before and after treatment. MDADI is a 36-item self-assessment with global, emotional, functional, and physical sub-scales. Total possible composite score range is 20-100 where 20 is extremely low functioning and 100 is high functioning. Data collected at baseline, 3 months, and 6 months, and 12 months post EBRT.

    Time frame: Assessed at 3 months and 6 months post EBRT (6 months and 9 months post-baseline). Originally pre-specified to be assessed at 12 months post EBRT, data not collected

  8. Stimulated Salivary Flow

    Stimulated Salivary Flow before and after treatment (mL/min). Data collected at baseline, 3 months, and 6 months post EBRT.

    Time frame: up to 6 months post completion of EBRT (up to 9 months on study)

  9. EORTC QLQ-C30 Scores

    The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) is a 30-item instrument measures quality of life in cancer patients. It is scored from 0-100 where higher scores indicate higher level of response in function, symptomatology, or global health.

    Time frame: up to 6 months post completion of EBRT (up to 9 months on study)

  10. Xerostomia Quality-of-Life Scale (XeQoLS) Scores

    The XeQoLS questionnaire measures the effects of xerostomia on oral health-related quality of life. The questionnaire consists of 15 items, each rated on a 0-to-4 point Likert scale, for a total possible range of scores from 0 to 60, with higher scores indicating more severe symptom burden.

    Time frame: up to 6 months post completion of EBRT (up to 9 months on study)

  11. Xerostomia Inventory Score

    The Xerostomia Inventory is an 11-item survey scored on a 5 point-likert scale (never, hardly ever, occasionally, fairly often, very much). Total possible range of scores is from 11-55, with higher scores indicating increased mouth dryness.

    Time frame: up to 6 months post completion of EBRT (up to 9 months on study)

07

Results

Posted Aug 15, 2024

Participant flow

Participants were enrolled from October 2020 to February 2022 at the UW Hospital and Clinics.

CLR Dose Level 1: 15.6mCi
Participant flow — CLR Dose Level 1: 15.6mCi
MilestoneCLR 131 Dose Escalation
Started4
Participants with dose limiting toxicities1
Completed4
Not completed0
Dose Held at Dose Level 1: 15.6mCi
Participant flow — Dose Held at Dose Level 1: 15.6mCi
MilestoneCLR 131 Dose Escalation
Started12
Completed treatment12
Primary analysis population12
Overall response rate analysis population11
Completed baseline salivary measures10
Completed 3 months post ebrt salivary measures9
Completed 6 months post ebrt salivary measures5
Completed 12 months post ebrt qol measures0
Died while on study8
Completed12
Not completed0

Outcome measures

PrimaryIncidence of Treatment Related Adverse Events

Incidence of adverse events assessed using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Adverse Events Grading (1 = mild, 2 = moderate, 3 = severe, 4 = life threatening, and 5 = death)

Time frame:
up to 18 weeks
Reported as:
Count of participants · Participants
Incidence of Treatment Related Adverse Events
ParticipantsGrade 1Grade 2Grade 3Grade 4
Blood and lymphatic system disorders: Anemia4241
Blood and lymphatic system disorders: Febrile neutropenia0020
Gastrointestinal disorders: Dry mouth2100
Gastrointestinal disorders: Dysphagia0200
Gastrointestinal disorders: Mucositis oral1010
Gastrointestinal disorders: Nausea0100
Gastrointestinal disorders: Salivary Duct Inflammation1000
General disorders: Fatigue4200
General disorders: Fever1000
General disorders: Pain0100
Infections and infestations: Thrush0100
Injury, poisoning and procedural complications: Dermatitis Radiation1000
Investigations: Lymphocyte count decreased0054
Investigations: Neutrophil count decreased0117
Investigations: Platelet count decreased1136
Investigations: Thyroid stimulating hormone increased1000
Investigations: Weight loss0200
Investigations: White blood cell decreased0227
Metabolism and nutrition disorders: Anorexia1100
Musculoskeletal and connective tissue disorders: Fibrosis deep connective tissue1000
Nervous system disorders: Dysgeusia1000
Nervous system disorders: Headache1000
Respiratory, thoracic and mediastinal disorders: Oropharyngeal pain2000
PrimarySummary of Adverse Events Possibly Related to Treatment

Adverse Events Grading (1 = mild, 2 = moderate, 3 = severe, 4 = life threatening, and 5 = death)

Time frame:
up to 18 weeks
Reported as:
Count of participants · Participants
Summary of Adverse Events Possibly Related to Treatment
ParticipantsAll Adverse EventsAdverse Events Greater Than or Equal to Grade 3
Thrombocytopenia119
Leukopenia119
Lymphopenia99
Neutropenia98
Anemia115
Fatigue60
Dry mouth30
Pain, Oral and Oropharyngeal30
Febrile neutropenia22
Mucositis oral21
Anorexia20
Dysphagia20
Weight loss20
SecondaryCLR 131 Tumor Uptake Via SPECT/CT Imaging

Investigators will use SPECT/CT imaging scans to predict the adsorbed dose of CLR 131 to tumors with the Monte Carlo method.

Time frame:
Up to 8 days
Reported as:
Mean · gray (Gy)
CLR 131 Tumor Uptake Via SPECT/CT Imaging
gray (Gy)CLR 131
CLR 131 Tumor Uptake Via SPECT/CT Imaging6.23 (2.65 to 8.69)
SecondaryMedian Radiation Treatment Time
Time frame:
up to 14 weeks
Reported as:
Mean · days
Median Radiation Treatment Time
daysCLR 131
Median Radiation Treatment Time43 (36 to 44)
SecondaryNumber of Dose Delays
Time frame:
up to 14 weeks
Reported as:
Count of units · doses
Number of Dose Delays
dosesCLR 131
Due to Toxicity0
Due to Production Difficulties1
SecondaryResponse Rates

Complete response (CR), disappearance of all tumors; Partial response (PR), at least 30% decrease in the sum of the longest diameter of target tumors; Stable disease (SD), no increase or decrease to tumor size; Progressive disease (PD), increasing tumor size. RECIST v1.1, Response Evaluation Criteria in Solid Tumors version 1.

Time frame:
6 months post completion of EBRT, up to 9 months on study
Reported as:
Count of participants · Participants
Response Rates
ParticipantsCLR 131
Complete Response7
Partial Response1
Stable Disease1
Progressive Disease2
SecondaryOverall Response Rate (ORR)

ORR defined as the proportion of subjects who experience either a partial response or complete response within 6 months post completion of EBRT as measured by standard of care imaging (e.g. CT, MR, PET-MR).

Time frame:
6 months post completion of EBRT, up to 9 months on study
Reported as:
Count of participants · Participants
Overall Response Rate (ORR)
ParticipantsCLR 131
Overall Response Rate (ORR)8
SecondarySwallow Function: DIGEST Scale

Swallow function assessed by Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale before and after treatment. The DIGEST scale cross references a clinician determined 'safety' grade with an 'efficiency' grade for an overall score between 0-4 where 0 is asymptomatic and 4 is life threatening. Data collected at baseline, 3 months, and 6 months post completion of external beam radiation therapy (EBRT).

Time frame:
up to 6 months post completion of EBRT (up to 9 months on study)
Reported as:
Median · score on a scale
Swallow Function: DIGEST Scale
score on a scaleDIGEST Overall GradeDIGEST Safety GradeDIGEST Efficacy Grade
baseline2 ± 1.0751 ± 0.94283 ± 1.633
3 months post EBRT2 ± 1.301 ± 0.9283 ± 1.58
6 months post EBRT3 ± 1.32 ± 1.143 ± 1.34
SecondaryQuality of Life: MDADI Score

Quality of life assessed by MD Anderson Dysphagia Inventory score (MDADI) before and after treatment. MDADI is a 36-item self-assessment with global, emotional, functional, and physical sub-scales. Total possible composite score range is 20-100 where 20 is extremely low functioning and 100 is high functioning. Data collected at baseline, 3 months, and 6 months, and 12 months post EBRT.

Time frame:
Assessed at 3 months and 6 months post EBRT (6 months and 9 months post-baseline). Originally pre-specified to be assessed at 12 months post EBRT, data not collected
Reported as:
Median · score on a scale
Quality of Life: MDADI Score
score on a scaleCLR 131
baseline71.6 ± 15.9
3 months post EBRT62.1 ± 20.6
6 months post EBRT55.8 ± 7.68
Statistical analysis
  • CLR 131 · Wilcoxon Signed Rank Tests · p = 0.173 · Median difference (final values): -4.22 · 95% CI -12.64 to 4.24
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.225 · Median difference (final values): -9.998 · 95% CI -28.43 to 7.39
SecondaryStimulated Salivary Flow

Stimulated Salivary Flow before and after treatment (mL/min). Data collected at baseline, 3 months, and 6 months post EBRT.

Time frame:
up to 6 months post completion of EBRT (up to 9 months on study)
Reported as:
Median · ml/min
Stimulated Salivary Flow
ml/minCLR 131
baseline0.24 ± 0.26
3 months post EBRT0.18 ± 0.10
6 months post EBRT0.21 ± 0.21
Statistical analysis
  • CLR 131 · Wilcoxon Signed Rank Tests · p = 0.779 · Median difference (final values): -0.037 · 95% CI -0.246 to 0.09
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.465 · Median difference (final values): -0.049 · 95% CI -0.218 to 0.12
SecondaryEORTC QLQ-C30 Scores

The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) is a 30-item instrument measures quality of life in cancer patients. It is scored from 0-100 where higher scores indicate higher level of response in function, symptomatology, or global health.

Time frame:
up to 6 months post completion of EBRT (up to 9 months on study)
Reported as:
Median · score on a scale
EORTC QLQ-C30 Scores
score on a scaleEORTC QLQ-C30 Functional ScoresEORTC QLQ-C30 Symptom ScoresEORTC QLQ-C30 Global Health Status Scores
baseline76.7 ± 16.723.08 ± 17.9250 ± 13.82
3 months post EBRT72.2 ± 13.126.92 ± 12.2854.2 ± 19.32
6 months post EBRT71.1 ± 11.228.21 ± 19.3958.3 ± 15.59
Statistical analysis
  • EORTC QLQ-C30 Functional Scores · Wilcoxon Signed Rank Tests · p = 0.213 · Median difference (final values): -4.444 · 95% CI -14.4 to 4.4
  • EORTC QLQ-C30 Functional Scores · Wilcoxon Signed Rank Test · p = 0.686 · Median difference (final values): -6.667 · 95% CI -17.8 to 20
  • EORTC QLQ-C30 Symptom Scores · Wilcoxon Signed Rank Test · p = 0.498 · Median difference (final values): 3.846 · 95% CI -0.769 to 12.82
  • EORTC QLQ-C30 Symptom Scores · Wilcoxon Signed Rank Test · p = 0.416 · Median difference (final values): 10.256 · 95% CI -15.39 to 35.89
  • EORTC QLQ-C30 Global Health Status Scores · Wilcoxon Signed Rank Test · p = 0.778 · Median difference (final values): -8.33 · 95% CI -20.84 to 16.67
  • EORTC QLQ-C30 Global Health Status Scores · Wilcoxon Signed Rank Test · p = 0.89 · Median difference (final values): 0 · 95% CI -25 to 25
SecondaryXerostomia Quality-of-Life Scale (XeQoLS) Scores

The XeQoLS questionnaire measures the effects of xerostomia on oral health-related quality of life. The questionnaire consists of 15 items, each rated on a 0-to-4 point Likert scale, for a total possible range of scores from 0 to 60, with higher scores indicating more severe symptom burden.

Time frame:
up to 6 months post completion of EBRT (up to 9 months on study)
Reported as:
Median · score on a scale
Xerostomia Quality-of-Life Scale (XeQoLS) Scores
score on a scaleCLR 131
baseline15 ± 14.4
3 months post EBRT16.5 ± 16.9
6 months post EBRT18 ± 13.1
Statistical analysis
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.138 · Median difference (final values): 3.5 · 95% CI -2 to 9.5
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.225 · Median difference (final values): 6 · 95% CI -10 to 16
SecondaryXerostomia Inventory Score

The Xerostomia Inventory is an 11-item survey scored on a 5 point-likert scale (never, hardly ever, occasionally, fairly often, very much). Total possible range of scores is from 11-55, with higher scores indicating increased mouth dryness.

Time frame:
up to 6 months post completion of EBRT (up to 9 months on study)
Reported as:
Median · score on a scale
Xerostomia Inventory Score
score on a scaleCLR 131
baseline34.5 ± 9.38
3 months post EBRT34.5 ± 10.75
6 months post EBRT36.0 ± 8.08
Statistical analysis
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.674 · Median difference (final values): 0.500 · 95% CI -3 to 5
  • CLR 131 · Wilcoxon Signed Rank Test · p = 0.892 · Median difference (final values): 0 · 95% CI -6 to 6

Adverse events

Collected over up to 85 days. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
CLR 131 Dose Escalation8/12 (66.7%)4/12 (33.3%)12/12 (100%)
Most frequent serious events
Most frequent serious events
EventCLR 131 Dose Escalation
Febrile neutropeniaBlood and lymphatic system disorders2/12
AnemiaBlood and lymphatic system disorders1/12
LaryngitisInfections and infestations1/12
Metabolism and nutrition disorders - Other, specifyMetabolism and nutrition disorders1/12
Tumor painNeoplasms benign, malignant and unspecified (incl cysts and polyps)1/12
AspirationRespiratory, thoracic and mediastinal disorders1/12
Respiratory failureRespiratory, thoracic and mediastinal disorders1/12
Most frequent other events
Showing 10 of 52
Most frequent other events
EventCLR 131 Dose Escalation
White blood cell decreasedInvestigations11/12
AnemiaBlood and lymphatic system disorders10/12
Lymphocyte count decreasedInvestigations10/12
Neutrophil count decreasedInvestigations10/12
Platelet count decreasedInvestigations9/12
FatigueGeneral disorders8/12
Mucositis oralGastrointestinal disorders6/12
Dermatitis radiationInjury, poisoning and procedural complications6/12
Dry mouthGastrointestinal disorders5/12
AnorexiaMetabolism and nutrition disorders5/12

Baseline characteristics

Age, Continuous
Age, Continuous(years)CLR 131 Dose Escalation
Median65.5 (47 to 84)
Age, Customized
Age, Customized(Participants)CLR 131 Dose Escalation
40-49 years2
50-59 years3
60-69 years2
70-79 years3
80-89 years2
Sex: Female, Male
Sex: Female, Male(Participants)CLR 131 Dose Escalation
Female3
Male9
Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)CLR 131 Dose Escalation
Hispanic or Latino0
Not Hispanic or Latino12
Unknown or Not Reported0
Race (NIH/OMB)
Race (NIH/OMB)(Participants)CLR 131 Dose Escalation
American Indian or Alaska Native0
Asian0
Native Hawaiian or Other Pacific Islander0
Black or African American0
White12
More than one race0
Unknown or Not Reported0
Region of Enrollment
Region of Enrollment(participants)CLR 131 Dose Escalation
United States12
ECOG Performance Status
ECOG Performance Status(Participants)CLR 131 Dose Escalation
ECOG 09
ECOG 13
Primary Tumor Site
Primary Tumor Site(Participants)CLR 131 Dose Escalation
Oropharynx5
Nasopharynx1
Larynx1
Oral cavity4
Salivary Gland1

5 further baseline measures are reported on the registry.

08

Study locations

2 sites
  • UW Cancer Center Johnson Creek
    Johnson Creek, Wisconsin 53038, United States
  • University of Wisconsin Carbone Cancer Center
    Madison, Wisconsin 53792, United States
09

References and documents

Publications

  • Bruce JY, Burr A, Kimple RJ, Adam DP, Yu M, Piaskowski SM, Glazer TA, Hill P, Hartig GK, McCulloch TM, Wieland AM, Trask D, Oliver K, Longcor J, Rogus-Pulia N, Cho SY, Bednarz B, Harari PM. Safety and toxicity of Iopofosine I 131 (CLR 131) with external beam radiation therapy in recurrent or metastatic head and neck cancer: results of a phase 1 single-centre, open-label, single-arm, dose escalation and dose expansion study. EBioMedicine. 2025 Jan;111:105496. doi: 10.1016/j.ebiom.2024.105496. Epub 2024 Dec 12. PubMed 39671752 ↗

Study documents

  • Protocol and statistical analysis plan · Oct 4, 2022
  • Informed consent form · Oct 6, 2022

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 2, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT04105543
Lead sponsor
University of Wisconsin, Madison
Collaborators
National Institute of Dental and Craniofacial Research (NIDCR), Cellectar Biosciences, Inc.
Responsible party
Sponsor
First posted
Sep 26, 2019
Start date
Dec 20, 2019
Primary completion
Sep 19, 2022
Completion
Feb 1, 2024
Results posted
Aug 15, 2024
Last update
Sep 2, 2025

Study contacts

Justine Bruce, MD
principal investigator · University of Wisconsin, Madison

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Jul 2024. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Head and Neck Neoplasms→

Other studies from this sponsor

University of Wisconsin, Madison

Start the discussion