Summary
Tamoxifen Citrate has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Lung Cancer would be drug repurposing rather than first-in-human development. This does not mean it is approved for Lung Cancer. ClinicalTrials.gov lists 4 registered trials linking Tamoxifen Citrate to Lung Cancer: 3 have completed; 1 is terminated, withdrawn, suspended or of unknown status. The most advanced is Phase 4 (NCT00999921). The largest enrolment is 260 participants (NCT00896155). Registration activity spans 1994 to 2008. No published literature item is linked to Tamoxifen Citrate and Lung Cancer in the OSMF database yet, so the record rests on registry entries alone. Registry entries describe intent to study, not outcomes.
The RepurpOS disease-intelligence file for Lung Cancer ranks 465 candidate therapeutics from Open Targets, ChEMBL, DGIdb and PubMed; only a minority carry direct clinical evidence, and this page covers one of those. Spontaneous remission context recorded for the condition: Spontaneous regression is rare (<0.5% of cases); 5-year survival without treatment: <5% for advanced NSCLC; ~20% for stage I-II with surgery.
Evidence table
| Evidence tier | A · Strong |
|---|---|
| Evidence score | 33.5 (trials 13.5, literature 0.0, tier 15, approved bonus 5.0) |
| Registered trials | 4 total: 0 recruiting, 0 active / not yet recruiting, 3 completed, 1 other |
| Linked publications | 0 |
| Agent type | Drug (Small molecule) |
| Development stage (any indication) | Approved |
| Mechanism / class | Not recorded |
| Data sources | DGIdb |
| Linked via biomarker / target | BRCA1 |
How the evidence score is calculated
- Each registered trial scores by status (recruiting / active / enrolling 3, completed 2.5, not yet recruiting 2, unknown 1, terminated / withdrawn / suspended 0.5) plus a phase bonus (phase 3-4 +2, phase 2 +1, phase 1 +0.5). The trial component is capped at 30.
- Each literature item scores by design (Cochrane review 5, meta-analysis 4, systematic review 3, RCT 3, clinical trial publication 2, curated reference 1.5, other PubMed record 1). The literature component is capped at 30.
- The existing evidence tier adds 15 (A / Strong), 10 (B / Moderate), 5 (C / Preliminary) or 0 (D / Anecdotal).
- Agents approved for any indication (max clinical phase 4) add 5, because an approved agent has an established safety profile that lowers the barrier to repurposing trials.
- The score ranks what has been studied, not what works. It does not read effect sizes or directions of effect.
Registered clinical trials
| NCT ID | Title | Status | Phase | Enrolment |
|---|---|---|---|---|
| NCT00999921 | Effects of Tamoxifen in Premenopausal Women With Benign Breast Disease Not at High-Risk of Developing Breast Cancer 2008 | completed | Phase 4 | 256 |
| NCT00896155 | Trial of Concurrent Versus Sequential Tamoxifen With Radiotherapy in Breast Cancer Patients 2008 | status unknown | Phase 3 | 260 |
| NCT00002608 | Combination Chemotherapy and Tamoxifen in Treating Patients With Solid Tumors 1994 | completed | Phase 2 | 30 |
| NCT00847366 | Open Label Trial of Perifosine in Patients Currently Being Treated on Perifosine Trials in Solid Tumors or Multiple Myeloma 2008 | completed | Not applicable | 10 |
Published literature
No publication is linked to this pair yet.
Mechanism and notes
No mechanism of action is recorded for this pair in the source databases.
OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target BRCA1. The tier describes how well the drug-disease link is documented, not how well the drug works.
Frequently asked questions
Is Tamoxifen Citrate approved for Lung Cancer?
Tamoxifen Citrate has reached the approved stage (maximum clinical phase 4) for at least one indication, so its use in Lung Cancer would be drug repurposing rather than first-in-human development. This does not mean it is approved for Lung Cancer. Approval status for the specific indication should always be confirmed with the relevant regulator and prescribing information.
Is Tamoxifen Citrate in clinical trials for Lung Cancer?
ClinicalTrials.gov lists 4 registered trials linking Tamoxifen Citrate to Lung Cancer: 3 have completed; 1 is terminated, withdrawn, suspended or of unknown status. The most advanced is Phase 4 (NCT00999921). The largest enrolment is 260 participants (NCT00896155). Registration activity spans 1994 to 2008.
What does the evidence show for Tamoxifen Citrate in Lung Cancer?
Tamoxifen Citrate has 3 completed registered trials for Lung Cancer but no linked publication, which usually means results are unpublished, pending, or not yet matched to this record. OSMF's existing evidence tier for this pair is A (Strong), derived from the strength of the disease association recorded in DGIdb, in this case via the biomarker or target BRCA1. The tier describes how well the drug-disease link is documented, not how well the drug works.
Cite this page
Data: ClinicalTrials.gov, PubMed, Open Targets, ChEMBL, DGIdb and the OSMF therapeutic agent database. Last updated 2026-07-05. Page built 2026-10-07.