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Testing an Active Form of Tamoxifen (4-hydroxytamoxifen) Delivered Through Breast Skin to Control Ductal Carcinoma in Situ (DCIS) of the Breast

Phase IIB Pre-Surgical Trial of Oral Tamoxifen Versus Transdermal 4-hydroxytamoxifen in Women With DCIS of the Breast

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02993159
Enrollment
100
Registered
2016-12-15
Start date
2017-05-31
Completion date
2022-01-24
Last updated
2024-12-18

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

Conditions

Ductal Breast Carcinoma In Situ, Estrogen Receptor Positive

Brief summary

This randomized phase IIB trial studies how well tamoxifen or afimoxifene works in treating patients with estrogen receptor positive breast cancer. Estrogen can cause the growth of breast cancer cells. Hormone therapy using tamoxifen citrate or afimoxifene may fight breast cancer by blocking the use of estrogen by the tumor cells.

Detailed description

PRIMARY OBJECTIVES: I. To demonstrate that 2 mg once daily per breast of 4-hydroxytamoxifen (4-OHT) topical gel results in a reduction in the Ki-67 labeling index of ductal breast carcinoma in situ (DCIS) lesions that is not inferior to that seen with 20 mg daily oral tamoxifen citrate (TAM) for 4-10 weeks, when comparing the base-line diagnostic core biopsy to the therapeutic surgical excision sample. SECONDARY OBJECTIVES: I. To compare post-therapy changes in the oncotype DCIS-score between arms (this is a validated reverse transcriptase-polymerase chain reaction \[RT-PCR\] assay for Ki67, STK15, survivin, cyclin B1, MYBL2, PR, GSTM1). II. To compare between-group post-therapy changes in immunohistochemistry (IHC) markers: CD-68 macrophage marker as a surrogate for response to therapy, p16 and COX-2. III. To compare post-therapy changes in breast density, quantitative estimate, between arms. IV. To compare post-therapy breast tissue and plasma levels of TAM and its metabolites (N-desmethyl tamoxifen \[NDT\], \[E\] and \[Z\] isomers of 4-hydroxytamoxifen \[4-OHT\], N-desmethyl-4-hydroxytamoxifen \[endoxifen\]). V. To compare post-therapy breast tissue and plasma levels of estradiol and progesterone between arms (optional). VI. To compare the post-therapy fraction of participants demonstrating no residual DCIS. VII. To compare post-therapy changes in plasma proteins involved in coagulation: factors VIII and IX, von Willebrand factor, total protein S between arms. VIII. To compare post-therapy changes in plasma markers of systemic estrogenic effect (IGF-1, SHBG). IX. To compare post-therapy changes in symptoms as captured in the breast cancer prevention trial (BCPT) Eight Symptom Scale (BESS) questionnaire and skin reactions to 4-OHT gel. OUTLINE: Patients are randomized into 1 of 2 arms. ARM I: Patients apply afimoxifene gel to both breasts and receive placebo orally (PO) daily for 4-10 weeks in the absence of disease progression or unexpected toxicity. ARM II: Patients apply placebo gel to both breasts and receive tamoxifen citrate orally PO daily for 4-10 weeks in the absence of disease progression or unexpected toxicity. After completion of study treatment, patients are followed up at 1-2 weeks and 1 month after surgery.

Interventions

Applied to the breast

OTHERLaboratory Biomarker Analysis

Correlative studies

OTHERPlacebo

Given PO

DRUGTamoxifen Citrate

Given PO

Sponsors

National Cancer Institute (NCI)
CollaboratorNIH
BHR Pharma, LLC
CollaboratorINDUSTRY
Northwestern University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Screen-detected, estrogen receptor (ER) positive DCIS of the breast proven on core needle biopsy, defined as 10% positive cells; the presence of a focus suspicious for microinvasion will be allowed; the size of the DCIS in the core biopsy sample must total 5 mm (multiple cores can be summed) and must be estimated on the deepest step section (if step sections are taken) * Eastern Cooperative Oncology Group (ECOG) performance status =\< 1 (Karnofsky \>= 70%) * Participants must have acceptable organ and marrow function as defined below: Baseline lab parameters are not standard of care for initiation of tamoxifen therapy; a minimal panel will therefore be appropriate. * Leukocytes \>= 3,000/microliter * Absolute neutrophil count \>= 1,500/microliter * Platelets \>= 100,000/microliter * Total bilirubin within ≤1.5 x institutional upper limit of normal (ULN)institutional limits * Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase \[SGOT\])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase \[SGPT\]) =\< 1.5 x institutional upper limit of normal (ULN) * Creatinine within ≤1.5 x institutional upper limit of normal (ULN) institutional limits * Women of childbearing potential and their male partners must agree to use TWO effective forms of birth control (abstinence is not an allowed method) prior to study entry and for the duration of study participation, and for two months following the last dose of study medications; effective birth control methods are: copper IUD \[intrauterine device\], diaphragm/cervical cap/shield, spermicide, contraceptive sponge, condoms; women of childbearing potential must have a negative urine pregnancy test within seven days before starting study medications; should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her study physician immediately * Willingness to avoid exposing breast skin to natural or artificial sunlight (i.e. tanning beds) for the duration of the study * Ability to understand and the willingness to sign a written informed consent document

Exclusion criteria

* DCIS presentation as a palpable mass * Exogenous sex steroid use within 4 weeks prior to core needle biopsy * Prior ipsilateral breast cancer radiotherapy will be excluded; prior contralateral breast cancer therapy within 2 years will also be excluded * Skin lesions on the breast that disrupt the stratum corneum (eg eczema, ulceration) * History of endometrial neoplasia * History of thromboembolic disease (history of varicose veins and superficial phlebitis is allowed) * Current smokers * Current users of potent inhibitors of tamoxifen metabolism must be able to discontinue their use and switch to an alternative medication for the duration of participation, under the advice of their physician; if the physician feels that an alternative medication is not appropriate for the subject and the current medication is medically necessary, the subject will not be eligible; the drugs are listed below; many of these are not in clinical use at the moment; bupropion, celecoxib, chlorpheniramine, chlorpromazine, cimetidine, citalopram, clemastine, clomipramine, clozapine, cocaine, delavirdine, desipramine, diphenhydramine, doxepin, duloxetine, escitalopram, fluoxetine, haloperidol, halofantrine, hydroxyzine, imipramine, isoniazid, ketoconazole, methadone, methimazole, mibefradil, miconazole, nicardipine, paroxetine, pergolide, perphenazine, pioglitazone, pyrimethamine, quinidine, quinine, ranitidine, ritonavir, ropinirole, sertraline, terbinafine, thioridazine, ticlopidine, tranylcypromine, trazodone, tripelennamine * Prior use of SERMS or AIs including tamoxifen, raloxifene, anastrozole, letrozole, or exemestane for prevention or therapy within 5 years * Participants may not be receiving any other investigational agents within 30 days of enrollment or during this study * History of allergic reactions attributed to tamoxifen or compounds of similar chemical or biologic composition * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements * Pregnant women are excluded from this study; breastfeeding should be discontinued by nursing mothers who agree to participate in the study * Men are excluded from this study since DCIS of the breast is exceedingly rare in men, and there are no data regarding skin penetration of 4-OHT though male chest wall skin (which is thicker and hairier than female chest wall skin)

Design outcomes

Primary

MeasureTime frameDescription
Change in Ki-67 Labeling Indexbaseline to up to 10 weeksChange in the Ki-67 labelling index of DCIS lesions evaluated using immunohistochemistry

Secondary

MeasureTime frameDescription
Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolitesup to 10 weeksPost-therapy concentrations of 4-OHT and endoxifen in breast tissue samples
Post-therapy Plasma Levels of Tamoxifen and Its Metabolitesup to 10 weeksPost-therapy concentrations of 4-OHT and endoxifen in plasma samples
Ki-67 Labelling Index in the Terminal Duct Lobular Units (TDLUs)baseline to up to 10 weeksMean change in Ki-67 labelling index in the terminal duct lobular units (TDLUs)
Change in Oncotype DCIS-Scorebaseline to up to 10 weeksChange in Exact Sciences Oncotype Diagnosis Breast Ductal Carcinoma in Situ Score (Oncotype DCIS-Score), a clinical validated clinically validated, commercially available genomic test for patients with DCIS. Oncotype DCIS-Score Range is 0-100. A negative change in scores indicates a lower risk of recurrence (better outcome).
Change in Plasma Markers of Systemic Estrogenic Effect (SHBG)baseline to up to 10 weeksMean change in plasma markers of systemic estrogenic effect: SHBG.
Change in Plasma Markers of Systemic Estrogenic Effect (IGF-1)baseline to up to 10 weeksMean change in plasma markers of systemic estrogenic effect: IGF-1
Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.baseline to up to 10 weeksMean change in symptoms as captured using the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) questionnaire. A patient reported outcome, scores range from 0 (Not at All) to 4 (Extremely) when asked about experiencing symptoms. A positive change in scores indicates an increase in symptoms experienced and a negative change in scores indicates a decrease in symptoms experienced
Change in Plasma Proteins Involved in Coagulationbaseline to up to 10 weeksMean change in percentage of plasma proteins involved in coagulation: Factor VIII, Factor IX, von Willebrand Factor, and total protein S

Countries

United States

Participant flow

Participants by arm

ArmCount
Arm I (4-OHT Topical Gel, Placebo)
2mg 4-hydroxytamoxifen (4-OHT) topical gel applied once daily per breast and placebo PO daily for 4-10 weeks
47
Arm II (Placebo, Oral Tamoxifen)
placebo gel applied once daily per breast and 20mg oral tamoxifen citrate PO daily for 4-10 weeks
53
Total100

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyOpted out of surgery20
Overall StudyPhysician Decision01
Overall StudyProtocol Violation10
Overall StudySurgery postponed due to COVID-19 and started AI11
Overall StudyWithdrawal by Subject13

Baseline characteristics

CharacteristicArm II (Placebo, Oral Tamoxifen)TotalArm I (4-OHT Topical Gel, Placebo)
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
10 Participants19 Participants9 Participants
Age, Categorical
Between 18 and 65 years
43 Participants81 Participants38 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
5 Participants8 Participants3 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
45 Participants87 Participants42 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
3 Participants5 Participants2 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
6 Participants8 Participants2 Participants
Race (NIH/OMB)
Black or African American
7 Participants19 Participants12 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
6 Participants8 Participants2 Participants
Race (NIH/OMB)
White
34 Participants65 Participants31 Participants
Region of Enrollment
United States
53 participants100 participants47 participants
Sex: Female, Male
Female
53 Participants100 Participants47 Participants
Sex: Female, Male
Male
0 Participants0 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 470 / 53
other
Total, other adverse events
27 / 4733 / 53
serious
Total, serious adverse events
0 / 470 / 53

Outcome results

Primary

Change in Ki-67 Labeling Index

Change in the Ki-67 labelling index of DCIS lesions evaluated using immunohistochemistry

Time frame: baseline to up to 10 weeks

Population: Participants with DCIS tissue samples at baseline and post-therapy

ArmMeasureValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Ki-67 Labeling Index-1.0 percent positive cells
Arm II (Placebo, Oral Tamoxifen)Change in Ki-67 Labeling Index-4.8 percent positive cells
Secondary

Change in Oncotype DCIS-Score

Change in Exact Sciences Oncotype Diagnosis Breast Ductal Carcinoma in Situ Score (Oncotype DCIS-Score), a clinical validated clinically validated, commercially available genomic test for patients with DCIS. Oncotype DCIS-Score Range is 0-100. A negative change in scores indicates a lower risk of recurrence (better outcome).

Time frame: baseline to up to 10 weeks

Population: Participants with Oncotype-DCIS score at baseline and post-therapy

ArmMeasureValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Oncotype DCIS-Score-1.8 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Oncotype DCIS-Score-16 score on a scale
Secondary

Change in Plasma Markers of Systemic Estrogenic Effect (IGF-1)

Mean change in plasma markers of systemic estrogenic effect: IGF-1

Time frame: baseline to up to 10 weeks

Population: Participants with plasma samples at baseline and post-therapy

ArmMeasureValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Markers of Systemic Estrogenic Effect (IGF-1)-1.2 ng/ml
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Markers of Systemic Estrogenic Effect (IGF-1)-48 ng/ml
Secondary

Change in Plasma Markers of Systemic Estrogenic Effect (SHBG)

Mean change in plasma markers of systemic estrogenic effect: SHBG.

Time frame: baseline to up to 10 weeks

Population: Participants with plasma samples at baseline and post-therapy

ArmMeasureValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Markers of Systemic Estrogenic Effect (SHBG)-0.24 nmol/l
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Markers of Systemic Estrogenic Effect (SHBG)15 nmol/l
Secondary

Change in Plasma Proteins Involved in Coagulation

Mean change in percentage of plasma proteins involved in coagulation: Factor VIII, Factor IX, von Willebrand Factor, and total protein S

Time frame: baseline to up to 10 weeks

Population: Participants with plasma samples at baseline and post-therapy

ArmMeasureGroupValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Proteins Involved in CoagulationFactor VIII-0.50 percent
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Proteins Involved in CoagulationFactor IX0.07 percent
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Proteins Involved in CoagulationFactor S-2.9 percent
Arm I (4-OHT Topical Gel, Placebo)Change in Plasma Proteins Involved in CoagulationvWF14 percent
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Proteins Involved in CoagulationFactor S-11 percent
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Proteins Involved in CoagulationFactor VIII-8.8 percent
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Proteins Involved in CoagulationFactor IX2.2 percent
Arm II (Placebo, Oral Tamoxifen)Change in Plasma Proteins Involved in CoagulationvWF30 percent
Secondary

Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.

Mean change in symptoms as captured using the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) questionnaire. A patient reported outcome, scores range from 0 (Not at All) to 4 (Extremely) when asked about experiencing symptoms. A positive change in scores indicates an increase in symptoms experienced and a negative change in scores indicates a decrease in symptoms experienced

Time frame: baseline to up to 10 weeks

Population: Participants with BESS scores at baseline and post-therapy

ArmMeasureGroupValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Body Pain-0.10 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Bladder-0.06 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Gastrointestinal-0.05 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Body image0.04 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Vasomotor0.15 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Vaginal-0.03 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Sexual problems0.14 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Problem-0.01 score on a scale
Arm I (4-OHT Topical Gel, Placebo)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Cognitive0.09 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Problem-0.04 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Cognitive-0.31 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Body Pain-0.15 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Vasomotor0.53 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Gastrointestinal-0.06 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Sexual problems-0.04 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Bladder-0.29 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Body image-0.04 score on a scale
Arm II (Placebo, Oral Tamoxifen)Change in Symptoms as Captured in the Breast Cancer Prevention Trial (BCPT) Eight Symptom Scale (BESS) Questionnaire and Skin Reactions to 4-OHT Gel.Vaginal-0.18 score on a scale
Secondary

Ki-67 Labelling Index in the Terminal Duct Lobular Units (TDLUs)

Mean change in Ki-67 labelling index in the terminal duct lobular units (TDLUs)

Time frame: baseline to up to 10 weeks

Population: Participants with terminal duct lobular units (TDLUs) at baseline and post-therapy

ArmMeasureValue (MEAN)
Arm I (4-OHT Topical Gel, Placebo)Ki-67 Labelling Index in the Terminal Duct Lobular Units (TDLUs)-0.11 percent positive
Arm II (Placebo, Oral Tamoxifen)Ki-67 Labelling Index in the Terminal Duct Lobular Units (TDLUs)0.16 percent positive
Secondary

Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites

Post-therapy concentrations of 4-OHT and endoxifen in breast tissue samples

Time frame: up to 10 weeks

Population: Participants with post-therapy tissue samples

ArmMeasureGroupValue (MEDIAN)
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Superficial tissue sample4.2 ng/g
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Deep tissue sample3.8 ng/g
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Breast Tissue Levels of Tamoxifen and Its MetabolitesEndoxifen, Superficial tissue sample0.2 ng/g
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Deep tissue sample0.3 ng/g
Arm II (Placebo, Oral Tamoxifen)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Deep tissue sample13 ng/g
Arm II (Placebo, Oral Tamoxifen)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Superficial tissue sample6.0 ng/g
Arm II (Placebo, Oral Tamoxifen)Post-therapy Breast Tissue Levels of Tamoxifen and Its MetabolitesEndoxifen, Superficial tissue sample16 ng/g
Arm II (Placebo, Oral Tamoxifen)Post-therapy Breast Tissue Levels of Tamoxifen and Its Metabolites4-OHT, Deep tissue sample5.7 ng/g
Secondary

Post-therapy Plasma Levels of Tamoxifen and Its Metabolites

Post-therapy concentrations of 4-OHT and endoxifen in plasma samples

Time frame: up to 10 weeks

Population: Participants with post-therapy plasma samples

ArmMeasureGroupValue (MEDIAN)
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Plasma Levels of Tamoxifen and Its Metabolites4-OHT, Plasma0.2 ng/ml
Arm I (4-OHT Topical Gel, Placebo)Post-therapy Plasma Levels of Tamoxifen and Its MetabolitesEndoxifen, Plasma0.0 ng/ml
Arm II (Placebo, Oral Tamoxifen)Post-therapy Plasma Levels of Tamoxifen and Its Metabolites4-OHT, Plasma2.0 ng/ml
Arm II (Placebo, Oral Tamoxifen)Post-therapy Plasma Levels of Tamoxifen and Its MetabolitesEndoxifen, Plasma10.5 ng/ml

Source: ClinicalTrials.gov · Data processed: Feb 24, 2026