Bicalutamide
| 證據等級: L5 | 預測適應症: 10 個 |
目錄
Bicalutamide: From Prostate Cancer to Hypertrichosis
One-Sentence Summary
Bicalutamide is a non-steroidal antiandrogen that competitively blocks the androgen receptor (AR), originally used to treat prostate cancer. The TxGNN model predicts it may be effective for Hypertrichosis (pathological excessive hair growth, including drug-induced forms), with 0 clinical trials and 1 publication (a letter commenting on a retrospective review of 35 patients) currently supporting this direction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Prostate cancer |
| Predicted New Indication | Hypertrichosis |
| TxGNN Prediction Score | 99.69% |
| Evidence Level | L4 |
| Canada Market Status | ✗ Not Marketed |
| Number of DINs | 0 |
| Recommended Decision | Hold |
Why Is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available in this Evidence Pack. Based on known information, bicalutamide is a non-steroidal androgen receptor antagonist primarily used in prostate cancer. Its efficacy in androgen-sensitive disease is well-established, and mechanistically it may be applicable to hypertrichosis driven by androgen-induced follicular activation.
Androgens promote hair follicle growth in androgen-sensitive regions via AR signaling. Minoxidil, a widely used treatment for hair loss, can paradoxically cause systemic hypertrichosis (excessive hair growth in non-target areas) as a dose-dependent side effect. By blocking AR, bicalutamide may reduce androgen-driven follicular hypersensitivity and attenuate this unwanted response — a plausible secondary pharmacological application.
Critically, this predicted use represents a secondary indication — managing a side effect of another drug rather than treating primary disease. Furthermore, the mechanistic rationale applies only to androgen-mediated hypertrichosis; genetic forms (such as Ambras syndrome or isolated hair shaft abnormalities, also appearing in this prediction list) have distinct, non-androgen-dependent pathways where AR blockade would not be expected to help.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 35304167 | 2022 | Letter/Comment | Journal of the American Academy of Dermatology | Commentary on a retrospective review of 35 patients with female pattern hair loss, discussing bicalutamide’s potential role in reducing minoxidil-induced hypertrichosis; not an original clinical study |
Cytotoxicity
Bicalutamide meets the antineoplastic criteria: it is a first-line hormonal treatment for prostate cancer (androgen-sensitive malignancy) and belongs to the antiandrogen class of hormone therapy.
| Item | Content |
|---|---|
| Cytotoxicity Classification | Targeted hormonal therapy — Non-steroidal androgen receptor antagonist (not a conventional cytotoxic) |
| Myelosuppression Risk | Low — bicalutamide does not directly suppress bone marrow; hematological toxicity is not a primary concern |
| Emetogenicity Classification | Minimal — not associated with significant nausea or vomiting |
| Monitoring Items | Liver function tests (ALT/AST — hepatotoxicity risk), PSA (disease monitoring), blood glucose, complete blood count |
| Handling Protection | Standard oral medication precautions apply; bicalutamide is not classified as a hazardous cytotoxic agent requiring specialized chemotherapy handling |
Safety Considerations
Please refer to the package insert for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The entire supporting evidence base consists of a single letter/commentary referencing a retrospective case series of 35 patients; no prospective or interventional studies exist for bicalutamide in hypertrichosis. This level of evidence (L4) is insufficient to advance the indication, particularly given that the proposed use is a secondary application — managing a side effect of another drug — rather than treating a primary pathological condition.
To proceed, the following is needed:
- Detailed mechanism of action data (MOA) and full safety profile from DrugBank or published sources
- Package insert warnings and contraindications (currently a data gap; flagged as blocking for safety pre-screening)
- A prospective observational or small pilot study formally assessing bicalutamide for minoxidil-induced hypertrichosis in a defined population
- Risk-benefit assessment specific to the target population (typically women without prostate cancer), accounting for the systemic antiandrogen effects of bicalutamide in a non-oncology context
- Regulatory consultation on whether this constitutes an off-label use requiring a new indication filing or can be managed under compassionate/special access provisions
Note: While hypertrichosis ranks first in the TxGNN prediction list, the Evidence Pack also contains a significantly higher-evidence prediction for female breast carcinoma (Rank 9, Evidence Level L2, 1 active Phase 2 trial + 20 publications, recommendation: Proceed with Guardrails). If the research objective is to identify the most actionable repurposing candidate from this dataset, breast cancer — specifically AR-positive triple-negative breast cancer (LAR subtype) — represents the far stronger and more clinically mature opportunity.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.