Palbociclib
| 證據等級: L5 | 預測適應症: 4 個 |
目錄
- Palbociclib
- Palbociclib: From HR+/HER2- Breast Cancer to Four Candidate Indications (Screening Stage)
Palbociclib: From HR+/HER2- Breast Cancer to Four Candidate Indications (Screening Stage)
One-Sentence Summary
Palbociclib is a CDK4/6 inhibitor whose original indication (HR+/HER2- metastatic breast cancer) is not recorded in this evidence pack but is confirmed repeatedly in the supporting literature. This screening round produced four TxGNN-predicted indications, but only one — rheumatoid arthritis — has any mechanistic or case-level human evidence (L4); the other three (hyperthyroidism, thrombotic disease, THRB-mutant thyroid hormone resistance) have either no supporting evidence or evidence pointing in the wrong direction (increased thromboembolic risk rather than benefit).
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in structured fields (data gap); literature within this pack repeatedly confirms HR+/HER2- metastatic breast cancer as the approved use of CDK4/6 inhibitors including palbociclib |
| Germany Market Status | Not marketed |
| Number of Authorizations | 0 |
| Number of Candidate Indications Screened | 4 |
| Blocking Data Gap | TFDA label warnings/contraindications not yet retrieved (DG001) — blocks entry into S1 safety review for any candidate |
| Overall Recommended Decision | Hold |
Candidate Indications at a Glance
| Rank | Predicted Indication | TxGNN Score | Evidence Level | Decision Stage | Recommendation |
|---|---|---|---|---|---|
| 1 | Hyperthyroidism | 99.44% | L5 | S0 | Hold |
| 2 | Rheumatoid arthritis | 99.36% | L4 | S1 | Research Question |
| 3 | Thrombotic disease | 99.32% | L4 | S0 | Hold |
| 4 | Resistance to thyroid hormone (THRB mutation) | 99.30% | L5 | S0 | Hold |
Why is This Prediction Reasonable?
Detailed DrugBank mechanism-of-action data is flagged as a data gap in this evidence pack (DG002). Based on the literature evidence collected within the pack itself, palbociclib is consistently described as a CDK4/6 (cyclin-dependent kinase 4/6) inhibitor, approved for HR+/HER2- metastatic breast cancer, acting by blocking cell-cycle progression from G1 to S phase.
Rheumatoid arthritis (rank 2) is the only candidate with a coherent mechanistic story: synovial fibroblast overgrowth in RA is cell-cycle dependent, and CDK6 specifically has been shown to drive synovial hyperplasia in arthritic mouse models (PMID 39940918). A preclinical study combining CDK inhibition with cytokine blockade showed enhanced anti-arthritic effect without added immunosuppression (PMID 25165034), and a single human case report describes RA improvement in a breast cancer patient treated with palbociclib (PMID 33587021). This is biologically plausible but rests on one case report plus preclinical data — no prospective human trial exists.
Thrombotic disease (rank 3) is mechanistically not supportive of repurposing. The literature attached to this candidate is dominated by FAERS pharmacovigilance disproportionality analyses and real-world cohort/case data showing CDK4/6 inhibitors (including palbociclib) are associated with increased thromboembolic risk, not therapeutic benefit. The two attached clinical trials are unrelated to thrombosis as a treatment target (one is an oncology combination study, the other a withdrawn COVID-19 safety trial). This candidate should be read as a safety signal, not a repurposing opportunity.
Hyperthyroidism (rank 1) and THRB-mutant thyroid hormone resistance (rank 4) have zero supporting trials or literature. Both are flagged in the evidence pack itself as likely graph-embedding noise with no known biological rationale connecting CDK4/6 inhibition to thyroid receptor pathways.
Clinical Trial Evidence
Rheumatoid Arthritis
Currently no related clinical trials registered.
Thrombotic Disease
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT05468697 | Phase 1/2 | Active, not recruiting | 60 | Belzutifan + palbociclib vs. belzutifan alone in advanced renal cell carcinoma — an oncology combination-dosing study, not a thrombosis treatment trial (relevance grade C) |
| NCT05371275 | Phase 2 | Withdrawn (0 enrolled) | 0 | Planned safety study of palbociclib in hospitalized moderate COVID-19 to prevent thromboinflammation; withdrawn before enrollment (relevance grade C) |
Hyperthyroidism / Resistance to Thyroid Hormone (THRB)
Currently no related clinical trials registered.
Literature Evidence
Rheumatoid Arthritis
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 33587021 | 2021 | Case Report | Mod Rheumatol Case Rep | RA symptom improvement in a breast cancer patient treated with palbociclib |
| 40504547 | 2025 | Review | The Oncologist | CDK4/6 inhibitors may influence immune function, potentially triggering or modulating autoimmune disease in HR+/HER2- breast cancer patients |
| 25165034 | 2016 | Preclinical (animal model) | Ann Rheum Dis | CDK inhibition combined with cytokine blockade enhanced anti-arthritic effect in animal models without increasing immunosuppression |
| 39940918 | 2025 | Preclinical/Mechanistic (animal model) | Int J Mol Sci | CDK6-dependent (CDK4-independent) synovial hyperplasia identified in arthritic mice; notes palbociclib-induced myelosuppression in preclinical studies |
Thrombotic Disease
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 39123221 | 2024 | Pharmacovigilance (FAERS) | BMC Pharmacol Toxicol | Comparative adverse event analysis across CDK4/6 inhibitors (palbociclib, abemaciclib, ribociclib) via FDA FAERS |
| 39083396 | 2025 | Pharmacovigilance (FAERS) | Expert Opin Drug Saf | Disproportionality analysis of CDK4/6 inhibitor adverse events in FAERS |
| 41496429 | 2026 | Pharmacovigilance (FAERS) | Breast | Age-stratified toxicity patterns of CDK4/6 inhibitors in older women, FAERS analysis |
| 35300061 | 2022 | Cohort | Cancer Manag Res | Real-world thromboembolic event data in HR+/HER2- metastatic breast cancer patients on ribociclib-based regimens |
| 36794339 | 2023 | Pharmacovigilance + Systematic Review | Expert Opin Drug Saf | Thromboembolism profiles associated with CDK4/6 inhibitors — real-world pharmacovigilance plus systematic review |
| 38390439 | 2024 | Case Report (ribociclib) | SAGE Open Med Case Rep | Cerebral venous sinus thrombosis case in a patient on ribociclib |
| 37994878 | 2023 | Review | Expert Opin Drug Saf | Review of interstitial lung disease and other adverse events with CDK4/6 inhibitors |
| 39302147 | 2025 | Mechanistic | Cardiovasc Res | dsDNA enhances platelet activation and thrombosis via cGAS — general platelet biology, not palbociclib-specific |
| 27098250 | 2016 | Preclinical (animal model) | Circ Cardiovasc Genet | CDKN2A-deficiency and megakaryopoiesis/platelet activity in a hypercholesterolemic mouse model |
| 40623899 | 2025 | Guidance (largely irrelevant) | Zhonghua Xue Ye Xue Za Zhi | Chinese hemophilia B gene-therapy guidance; palbociclib mentioned only in passing regarding recent China market approval |
Hyperthyroidism / Resistance to Thyroid Hormone (THRB)
Currently no related literature available.
Germany Market Information
Palbociclib currently has no marketing authorization in Germany (0 licenses on record), so no product-level table is available.
Cytotoxicity
Palbociclib is an antineoplastic agent (approved use in HR+/HER2- metastatic breast cancer per literature within this pack; targeted small-molecule CDK4/6 inhibitor class).
| Item | Content |
|---|---|
| Cytotoxicity Classification | Targeted therapy (CDK4/6 inhibitor) — not a conventional cytotoxic agent |
| Myelosuppression Risk | Reported in preclinical literature (PMID 39940918); please refer to the package insert for graded frequency data (not available in this pack) |
| Emetogenicity Classification | Not specified in this evidence pack; please refer to the package insert |
| Monitoring Items | CBC with differential (myelosuppression); given the pharmacovigilance signal above, monitoring for thromboembolic symptoms is also advisable |
| Handling Protection | Cytotoxic/hazardous drug handling precautions should be followed pending confirmation via package insert |
Safety Considerations
Formal safety data (key warnings, contraindications, DDI) are not available in this evidence pack — please refer to the package insert for safety information.
- Evidence-derived signal (not from formal label data): Multiple independent FAERS pharmacovigilance analyses and a real-world cohort study within the literature evidence (PMID 39123221, 39083396, 41496429, 36794339, 35300061) consistently associate CDK4/6 inhibitors, including palbociclib, with an increased risk of thromboembolic events. This should be treated as a safety signal requiring confirmation against the official label, not as supporting evidence for a thrombotic-disease indication.
Conclusion and Next Steps
Decision: Hold
Rationale: Of the four TxGNN-predicted indications, three (hyperthyroidism, thrombotic disease, THRB-mutant thyroid hormone resistance) lack any indication-specific supportive evidence, and the thrombotic-disease candidate is contradicted by pharmacovigilance data pointing to increased risk rather than benefit. The remaining candidate, rheumatoid arthritis, has only preclinical and single-case-report support (L4) and has not entered controlled human testing. In addition, a blocking data gap (DG001: TFDA label warnings/contraindications not retrieved) prevents any candidate from formally entering S1 safety review.
To proceed, the following is needed:
- Retrieve TFDA/EMA label warnings and contraindications (resolves blocking gap DG001)
- Confirm DrugBank mechanism-of-action record (DG002)
- For the rheumatoid arthritis hypothesis: identify or design a prospective controlled human trial before advancing past the "Research Question" stage
- Formally assess baseline thromboembolic risk against the official label before considering any further indication work, given the pharmacovigilance signal identified
- Deprioritize hyperthyroidism and THRB-mutant thyroid hormone resistance absent new supporting evidence
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.