Asset profile

Letrozole

Small molecule

Approvedregulatory verdict

Evidence outlook

Approved — HR+/HER2- Metastatic Breast Cancer

Regulatory approval supersedes design-level evidence grading — the trials behind approval are preserved below as the drug's evidence history.

track record: Partial signal

How the evidence outlook works ↗

Featured trials

Research

Unlock featured-trial analysis

Research includes the instrumental studies, endpoints, key results, design grades, rationales and source links behind the Outlook.

Upcoming events

(62 total)

Estimated primary-completion dates from ClinicalTrials.gov — registry estimates, never confirmed readout dates; they can move as trials progress.

2026 (9)

August 2026 (1)

Phase 1/2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-08-23 · NCT05262400 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

September 2026 (1)

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-09-23 · NCT04557449 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2026 (7)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2026-12 · NCT06974929 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 3HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-12 · NCT05780567 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-12-01 · NCT04486911 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2026-12-31 · NCT07492394 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-12-31 · NCT04553133 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-12-31 · NCT05286437 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2026-12-31 · NCT05226871 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2027 (15)

January 2027 (1)

Phase 1/2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2027-01 · NCT02562118 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

February 2027 (1)

Phase 1/2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2027-02-26 · NCT01872260 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

March 2027 (2)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2027-03 · NCT07305246 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-03-01 · NCT06179303 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

April 2027 (2)

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-04-15 · NCT04614194 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-04-30 · NCT05900206 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

July 2027 (2)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2027-07 · NCT07394946 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-07-31 · NCT07054190 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

August 2027 (1)

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-08 · NCT05181033 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

October 2027 (2)

Phase 2HR+/HER2- Metastatic Breast CancerEnrolling by invitation

Est. primary completion 2027-10-01 · NCT06650748 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-10-31 · NCT04563507 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2027 (4)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-12 · NCT06555068 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-12-31 · NCT05582499 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-12-31 · NCT07014410 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2027-12-31 · NCT07285382 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2028 (12)

January 2028 (3)

Phase 2Low Grade Serous Ovarian Carcinoma, Adult Type Granulosa Cell TumorRecruiting

Est. primary completion 2028-01 · NCT05872204 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2028-01-30 · NCT07691333 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2028-01-31 · NCT05867251 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

March 2028 (1)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2028-03-01 · NCT07676331 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

April 2028 (1)

Phase 2HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2028-04-02 · NCT04568616 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

May 2028 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2028-05-31 · NCT05891093 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

June 2028 (2)

Phase 3HR+/HER2- Metastatic Breast CancerEnrolling by invitation

Est. primary completion 2028-06 · NCT05645536 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 3HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2028-06 · NCT02918084 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

August 2028 (2)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2028-08 · NCT06998407 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2028-08-15 · NCT05467891 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2028 (2)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2028-12 · NCT07389733 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2Breast Cancer, HER2-positiveRecruiting

Est. primary completion 2028-12-29 · NCT05035836 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2029 (11)

January 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2029-01-02 · NCT06760637 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

March 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-03-31 · NCT06757634 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

April 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-04 · NCT07492641 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

May 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-05 · NCT07174336 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

June 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-06-30 · NCT06507618 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

July 2029 (3)

Phase 3HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2029-07-01 · NCT07061717 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-07-13 · NCT04606446 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-07-31 · NCT07391774 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

August 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-08 · NCT06492616 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

September 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-09-07 · NCT05827081 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2029 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2029-12-18 · NCT06380751 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2030 (7)

July 2030 (1)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2030-07 · NCT05768139 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

August 2030 (1)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2030-08-31 · NCT07716046 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

September 2030 (2)

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2030-09 · NCT06953882 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2030-09-30 · NCT03424005 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

October 2030 (1)

Phase 3HR+/HER2- Metastatic Breast CancerActive not recruiting

Est. primary completion 2030-10 · NCT04584853 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2030 (2)

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2030-12 · NCT01042379 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HER2-positive Breast CancerNot yet recruiting

Est. primary completion 2030-12-30 · NCT07179939 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2031 (5)

April 2031 (1)

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2031-04-08 · NCT04852887 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

May 2031 (1)

Phase 1/2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2031-05-09 · NCT07288359 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

June 2031 (1)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2031-06-27 · NCT07679269 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

December 2031 (2)

Phase 2HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2031-12 · NCT07101159 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 2HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2031-12-31 · NCT07581834 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2032 (2)

May 2032 (2)

Phase 3HR+/HER2- Metastatic Breast CancerNot yet recruiting

Est. primary completion 2032-05-02 · NCT06223698 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

Phase 3HR+/HER2- Metastatic Breast CancerRecruiting

Est. primary completion 2032-05-30 · NCT06790693 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

2034 (1)

July 2034 (1)

Phase 2Human Epidermal Growth Factor 2 Negative Carcinoma of Breast, HER2-positive Breast Cancer, Breast CancerRecruiting

Est. primary completion 2034-07-01 · NCT06348134 · CT.gov ↗

What to watch

Research analysis

Source-grounded endpoint goals, benchmarks, comparator context, and caveats for this readout are included with Research.

See the full readout calendar ↗

All registered studies

Research

Unlock the complete ClinicalTrials.gov registry

Research includes every linked study, indication filters, phase grouping and featured-trial cross-links.

Competitive landscape

Research

Unlock the competitor landscape

Research compares assets by shared mechanism and indication, including each competitor's stage in the relevant market.