Cyclophosphamide and Sirolimus for the Treatment of Metastatic, RAI-refractory, Differentiated Thyroid Cancer

Study Overview
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Brief Summary
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This study will be a non-randomized pilot trial using Cyclophosphamide and Sirolimus for the treatment of metastatic differentiated thyroid cancer. Patients will be treated with Sirolimus 4 mg, PO, days 1-28 as well as Cyclophosphamide 100 mg, PO, days 1-5 and 15-19. Cycle length will be 28 days. Patients will be monitored closely for toxicity and undergo imaging to evaluate efficacy once every 2 cycles.

Official Title
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An Open Label Phase II Trial Evaluating the Efficacy of Cyclophosphamide and Sirolimus for the Treatment of Metastatic, RAI-refractory, Differentiated Thyroid Cancer

Conditions
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Metastatic Thyroid Cancer

Intervention / Treatment
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* Drug: Cyclophosphamide
* Drug: Sirolimus


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Histologically documented differentiated thyroid cancer with or without metastases, not amenable to curative treatment; or the patient has documented refusal of curative treatment Measurable disease (>10 mm) and have progression of disease based on RECIST criteria. Previously irradiated tumor lesions are not considered measurable unless they have progressed since radiation. Previous failure of Iodine-131 (131I) therapy or not candidates to receive 131I as assessed by treating physician. Age ≥ 18 years ECOG (Eastern Cooperative Oncology Group) performance status 0-2 Life expectance of ≥ 12 weeks 131I therapy not allowed within 24 weeks before entry (4 weeks if negative post-treatment scan) Adequate organ and marrow function Women of childbearing potential must have a negative serum or urine pregnancy test within 3 days prior to treatment Signed and dated informed consent document indicating that the patient (or legally acceptable representative) has been informed of all pertinent aspects of the trial prior to enrollment Willingness and ability to comply with scheduled visits, treatment plans, including willingness to take study medication, laboratory tests, and other study procedures Exclusion Criteria: Inability to obtain Foundation One testing on archival tissue, or, lack of previous Next Generation Sequencing Chemotherapy, tyrosine kinase inhibitor, or radiation therapy within 4 weeks Prior experimental therapy within 4 weeks of planned start of this trial 131I therapy within 24 weeks before entry (4 weeks if negative post-treatment scan) Previous treatment with an mTOR inhibitor Patients who are currently receiving treatment with strong inhibitors or inducers of CYP3A4 or P-glycoprotein that cannot be discontinued at least one week prior to the start of treatment with Cyclophosphamide and Sirolimus Impairment of GI (gastrointestinal) function or GI disease that may significantly alter the absorption of study medications (e.g., ulcerative diseases, uncontrolled nausea, vomiting, diarrhea, malabsorption syndrome, small bowel resection) including dependence on a G-Tube for administration of medications. A serious uncontrolled medical disorder or active infection that would impair their ability to receive study treatment Patients with known sensitivities to either cyclophosphamide and/or sirolimus Patients with known urinary outflow obstruction Dementia or significantly altered mental status that would prohibit the understanding or rendering of informed consent and compliance with the requirements of this protocol Patients (male and female) having procreative potential who are not willing or not able to use adequate contraception or practicing abstinence Women who are pregnant or breast-feeding Patients residing in prison

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cyclophosphamide and Sirolimus<br>Sirolimus 4 mg, PO, days 1-28 as well as Cyclophosphamide 100 mg, PO, days 1-5 and 15-19 | Drug: Cyclophosphamide<br>* Cyclophosphamide 100 mg, PO, days 1-5 and 15-19<br>Drug: Sirolimus<br>* Sirolimus 4 mg, PO, days 1-28<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of patients that respond to treatment | The primary measure of efficacy will be the overall response rate (ORR) which is defined as those achieving either complete response (CR) or partial response (PR). Partial response is defined as at least a 30% decrease in the sum of the longest diameter (LD) of target lesions. Complete response is defined as Disappearance of all target lesions, determined by two separate observations conducted not less than 4 weeks apart (there can be no appearance of new lesions) and the disappearance of all non-target lesions and normalization of tumor marker level. | Patients will be followed for response until progression or up to 2 Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of patients that experience toxicity | The number of patients that experience toxicity by type will be reported. | Patients are followed for toxicity up to 30 days after the last dose of study drug | 
| Median overall survival time | The median duration of time from start of treatment until death | Patients will be followed until death or up to 2 years | 
| Median progression free survival time | The median duration of time from start of treatment until progression. Progression is defined as at least a 20% increase in the sum of the LD (longest diameter) of target lesions, taking as reference the smallest sum LD recorded since the treatment started, or the appearance of one or more new lesions and/or unequivocal progression of existing non-target lesions. | Patients will be followed for response until progression or up to 2 Years |