A Phase 1/2 interventional study of Tamoxifen in Breast Cancer and Mammographic Density, sponsored by Karolinska Institutet. Completed. Open to female participants aged 40 Years to 74 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-02-06.
Sponsored by Karolinska Institutet · Phase 1/2, Interventional, and Prevention
A feasibility study, randomising to either 10 or 20 mg of tamoxifen. The primary aim is to identify the time to mammographic density change and piloting the procedures. It is known that a density change is seen after 12 months of 20 mg of tamoxifen, but the clinical experience indicates that an effect of drugs influencing mammographic density could be seen already after a few months. The second aim is to evaluate if there is a density change from 10 mg of tamoxifen equivalent to 20 mg.
The investigators want to conduct a feasibility study including 42 women who will be randomised to either 10 or 20 mg of daily oral tamoxifen. The primary aim of the study is to identify the time to mammographic density change and piloting the procedures. It is known that a density change is seen after 12 months of 20 mg of daily tamoxifen, but the clinical experience indicates that an effect of drugs influencing mammographic density could be seen already after a few months. The second aim of the pilot study is to see if there is a density change from 10 mg of tamoxifen equivalent to 20 mg and if there is a difference in adverse reactions between the two doses. Interim analysis will be performed at 6 months, monitoring both safety and level of mammographic density change.
Karolinska Institutet is the lead sponsor of 1,113 studies on the registry; 267 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Randomised dose of daily oral Tamoxifen 10mg, for 180 days
Drug: Tamoxifen
Randomised dose of daily oral Tamoxifen 20mg, for 180 days
Drug: Tamoxifen
A registered SERM drug, Tamoxifen.
Mammographic Breast Density
Mean change in mammographic breast density at 6 months compared to baseline (=0 months) for each dose arm, using the fully automated STRATUS method. The average percent density (fibroglandular dense tissue area divided by total breast area) of left and right breasts at baseline was calculated and compared with average percent density at the end of the trial period and density change was defined as the difference between these two measures.
Time frame: 6 months
Symptom Score
Symptom score change, compared to baseline for each dose arm. Questionnaires were used at 0, 1, 3, 6, 9 months. Vasomotor, gynecological, sexual, and musculoskeletal symptoms were assessed using a 5-grade Likert severity scale ranging from "no symptom at all" to "very much symptoms". A higher symptom score equals less symptoms, i.e. a better outcome. The questionnaire was based on the Functional Assessment of Cancer Therapy - Endocrine Subscale 7 (FACT-ES.7). The presented score was calculated as the sum of the last month's symptom severity levels and are presented as the absolute differences in symptom score on a scale ranging from any minus five to any plus five. A higher symptom score equals less symptoms, i.e. a better outcome.
Time frame: 9 months
| Milestone | Tamoxifen 10mg | Tamoxifen 20mg |
|---|---|---|
| Started | 23 | 19 |
| Completed | 18 | 15 |
| Not completed | 5 | 4 |
Mean change in mammographic breast density at 6 months compared to baseline (=0 months) for each dose arm, using the fully automated STRATUS method. The average percent density (fibroglandular dense tissue area divided by total breast area) of left and right breasts at baseline was calculated and compared with average percent density at the end of the trial period and density change was defined as the difference between these two measures.
| percentage of breast area | Tamoxifen 10mg | Tamoxifen 20mg |
|---|---|---|
| Mammographic Breast Density | -3.3 (-6.1 to -0.5) | -2.5 (-2.5 to 0.8) |
Symptom score change, compared to baseline for each dose arm. Questionnaires were used at 0, 1, 3, 6, 9 months. Vasomotor, gynecological, sexual, and musculoskeletal symptoms were assessed using a 5-grade Likert severity scale ranging from "no symptom at all" to "very much symptoms". A higher symptom score equals less symptoms, i.e. a better outcome. The questionnaire was based on the Functional Assessment of Cancer Therapy - Endocrine Subscale 7 (FACT-ES.7). The presented score was calculated as the sum of the last month's symptom severity levels and are presented as the absolute differences in symptom score on a scale ranging from any minus five to any plus five. A higher symptom score equals less symptoms, i.e. a better outcome.
| score on a scale | Tamoxifen 10mg | Tamoxifen 20mg |
|---|---|---|
| Symptom Score | 1.8 (-0.8 to 4.5) | 3.7 (0.5 to 6.8) |
Non-serious events are listed at a 2% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Tamoxifen 10mg | 0/23 (0%) | 0/23 (0%) | 18/23 (78.3%) |
| Tamoxifen 20mg | 0/19 (0%) | 0/19 (0%) | 18/19 (94.7%) |
| Event | Tamoxifen 10mg | Tamoxifen 20mg |
|---|---|---|
| Night sweatsEndocrine disorders | 15/23 | 18/19 |
| Menopausal hot flushesEndocrine disorders | 14/23 | 17/19 |
| muscle cramps (e.g. in legs)Musculoskeletal and connective tissue disorders | 14/23 | 16/19 |
| Dryness vaginalReproductive system and breast disorders | 11/23 | 14/19 |
| weight gainMetabolism and nutrition disorders | 12/23 | 14/19 |
| VomitingMetabolism and nutrition disorders | 12/23 | 13/19 |
| Vaginal dischargeReproductive system and breast disorders | 7/23 | 11/19 |
| Pain in jointsMusculoskeletal and connective tissue disorders | 12/23 | 11/19 |
| Sexual feeling decreasedReproductive system and breast disorders | 9/23 | 10/19 |
| Fragile mucous membranes/ Mucous membrane disorderReproductive system and breast disorders | 7/23 | 10/19 |
| Age, Continuous(years) | Tamoxifen 10mg | Tamoxifen 20mg | Total |
|---|---|---|---|
| Mean | 59.74 ± 8.48 | 62.32 ± 6.74 | 61.5 ± 5.10 |
| Sex: Female, Male(Participants) | Tamoxifen 10mg | Tamoxifen 20mg | Total |
|---|---|---|---|
| Female | 23 | 19 | 42 |
| Male | 0 | 0 | 0 |
| Region of Enrollment(participants) | Tamoxifen 10mg | Tamoxifen 20mg | Total |
|---|---|---|---|
| Sweden | 23 | 19 | 42 |
No study locations are listed for this record.
This study is completed, as verified in Feb 2025. You cannot join it, but the record below documents what was studied.
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Karolinska Institutet