Letrozole
Highest phase reached
Approved
Drug type
Small molecule
First approval year
1997
- First approval year
- 1997
- Listing at source
- Listed
- Highest phase reached
- Approved
- Drug type
- Small molecule
- Drug name
- Letrozole
- Molecular weight
- 285.31
- Structure (SMILES)
- N#Cc1ccc(C(c2ccc(C#N)cc2)n2cncn2)cc1
- femara
- Femara
- letrozole
- Letrozole
- letrozole component of kisqali femara co pack
- Letrozole component of kisqali femara co-pack
- Aromatase Inhibitors (Femara)
- cgs 20267
- CGS 20267
- CGS-20267
- cgs20267
- CGS20267
- Femara
- Femara (Sequence 1)
- Femara (Sequence 2)
- Femara® Tablets 2.5 mg
- kisqali femara co pack component letrozole
- Kisqali femara co-pack component letrozole
- letrozol
- Letrozol
- letrozole
- Letrozole
- Letrozole (2.5 mg)
- Letrozole (aromatase inhibitor)
- Letrozole (Aromatase Inhibitors)
- letrozole (Femara)
- Letrozole (Femara)
- Letrozole [EP IMPURITY]
- Letrozole [EP MONOGRAPH]
- Letrozole [HSDB]
- Letrozole [INN]
And 35 more, listed on the interactive page.
- ATC classification codes
- L02BG04
Sources for recorded values
- CAS registry numbers
- 112809-51-5
- ChEMBL ID
- CHEMBL1444
- InChIKey
- HPJKCIUCZWXJDR-UHFFFAOYSA-N
- PubChem compound IDs
- 3902
- RxNorm IDs (RxCUI)
- 72965
- FDA ingredient codes (UNII)
- 7LKK855W8I
- Applicant
- NOVARTIS PHARMS
- Approval date
- 25 Jul 1997
- Application number
- NDA020726
- First in class
- No
- Orphan designation
- No
- Availability
- Prescription only
- Pharmacology name
- letrozole
- Type
- Synthetic organic
- Drug name stem
- -rozole
- Approval recorded by Guide to Pharmacology
- Yes
Administration routes
- Oral
- Action
- Inhibition
- Action type
- Inhibitor
- Target
- CYP19A1
- Gene symbol
- CYP19A1
- Protein identifier
- P11511
- Median affinity
- 10.7
- Affinity units
- pKi
- Primary target
- Yes
- Mechanism
- Cytochrome P450 19A1 inhibitor
- Action type
- Inhibitor
- Target
- Aromatase
- Protein identifier
- P11511
Open Targets mechanisms
- Mechanism
- Cytochrome P450 19A1 inhibitor
- Action type
- Inhibitor
- Target
- Aromatase
DrugCentral mechanisms
- Action type
- Inhibitor
- Gene symbol
- CYP19A1
- Protein identifier
- P11511
- Organism
- Homo sapiens
- Target development level
- Clinical
- Condition
- Azoospermia
- Highest recorded phase
- 3
- Condition identifier
- EFO:0000279
- Subject identifier
- D053713
- Condition
- Breast Neoplasms
- Highest recorded phase
- 4
- Condition identifier
- EFO:0000305
- Subject identifier
- D001943
- Condition
- Carcinoma
- Highest recorded phase
- 2
- Condition identifier
- EFO:0000313
- Subject identifier
- D002277
- Condition
- Carcinoma, Intraductal, Noninfiltrating
- Highest recorded phase
- 3
- Condition identifier
- EFO:0000432
- Subject identifier
- D002285
- Condition
- Carcinoma, Endometrioid
- Highest recorded phase
- 1
- Condition identifier
- EFO:0000466
- Subject identifier
- D018269
- Condition
- Infertility
- Highest recorded phase
- 3
- Condition identifier
- EFO:0000545
- Subject identifier
- D007246
- Condition
- Carcinoma, Lobular
- Highest recorded phase
- 2
- Condition identifier
- EFO:0000553
- Subject identifier
- D018275
- Condition
- Leiomyosarcoma
- Highest recorded phase
- 2
- Condition identifier
- EFO:0000564
- Subject identifier
- D007890
- Condition
- Mesothelioma
- Highest recorded phase
- 1
- Condition identifier
- EFO:0000588
- Subject identifier
- D008654
- Condition
- Neoplasms
- Highest recorded phase
- 4
- Condition identifier
- EFO:0000616
- Subject identifier
- D009369
- Condition
- Polycystic Ovary Syndrome
- Highest recorded phase
- 3
- Condition identifier
- EFO:0000660
- Subject identifier
- D011085
- Condition
- Leiomyoma
- Highest recorded phase
- 1
- Condition identifier
- EFO:0000731
- Subject identifier
- D007889
- Condition
- Endometriosis
- Highest recorded phase
- 2
- Condition identifier
- EFO:0001065
- Subject identifier
- D004715
- Condition
- Ovarian Neoplasms
- Highest recorded phase
- 3
- Condition identifier
- EFO:0001075
- Subject identifier
- D010051
- Condition
- Uterine Cervical Neoplasms
- Highest recorded phase
- 2
- Condition identifier
- EFO:0001416
- Subject identifier
- D002583
- Condition
- Pregnancy
- Highest recorded phase
- 3
- Condition identifier
- EFO:0002950
- Subject identifier
- D011247
- Condition
- Carcinoma, Non-Small-Cell Lung
- Highest recorded phase
- 1
- Condition identifier
- EFO:0003060
- Subject identifier
- D002289
- Condition
- Brain Neoplasms
- Highest recorded phase
- 0.5
- Condition identifier
- EFO:0003833
- Subject identifier
- D001932
- Condition
- Uterine Neoplasms
- Highest recorded phase
- 2
- Condition identifier
- EFO:0003859
- Subject identifier
- D014594
- Condition
- Breast Neoplasms
- Highest recorded phase
- 4
- Condition identifier
- EFO:0003869
- Subject identifier
- D001943
- Condition
- Osteoporosis
- Highest recorded phase
- 3
- Condition identifier
- EFO:0003882
- Subject identifier
- D010024
- Condition
- Hemangiosarcoma
- Highest recorded phase
- 2
- Condition identifier
- EFO:0003968
- Subject identifier
- D006394
- Condition
- Endometrial Neoplasms
- Highest recorded phase
- 3
- Condition identifier
- EFO:0004230
- Subject identifier
- D016889
- Condition
- Infertility, Male
- Highest recorded phase
- 2
- Condition identifier
- EFO:0004248
- Subject identifier
- D007248
- Condition
- Triple Negative Breast Neoplasms
- Highest recorded phase
- 2
- Condition identifier
- EFO:0005537
- Subject identifier
- D064726
And 26 more, listed on the interactive page.
- Condition identifier
- EFO_0000279
- Highest recorded phase
- 3
- Condition identifier
- EFO_0000305
- Condition identifier
- EFO_0000313
- Highest recorded phase
- 2
- Condition identifier
- EFO_0000466
- Condition identifier
- EFO_0000545
- Highest recorded phase
- 3
- Condition identifier
- EFO_0000564
- Highest recorded phase
- 2
- Condition identifier
- EFO_0000616
- Condition identifier
- EFO_0000660
- Highest recorded phase
- 3
- Condition identifier
- EFO_0000731
- Highest recorded phase
- 1
- Condition identifier
- EFO_0001065
- Highest recorded phase
- 2
- Condition identifier
- EFO_0001073
- Highest recorded phase
- 3
- Condition identifier
- EFO_0001075
- Highest recorded phase
- 3
- Condition identifier
- EFO_0001416
- Highest recorded phase
- 2
- Condition identifier
- EFO_0002950
- Highest recorded phase
- 2
- Condition identifier
- EFO_0002950
- Highest recorded phase
- 3
- Condition identifier
- EFO_0003869
- Highest recorded phase
- 3
- Condition identifier
- EFO_0003882
- Highest recorded phase
- 3
- Condition identifier
- EFO_0004230
- Highest recorded phase
- 2
- Condition identifier
- EFO_0004248
- Highest recorded phase
- 2
- Condition identifier
- EFO_0008509
- Highest recorded phase
- 1
- Condition identifier
- EFO_0008587
- Highest recorded phase
- 3
- Condition identifier
- EFO_0009708
- Highest recorded phase
- 2
- Condition identifier
- EFO_0009870
- Highest recorded phase
- 2
- Condition identifier
- EFO_1000649
- Condition identifier
- EFO_1000954
And 86 more, listed on the interactive page.
- Event
- alopecia
- Reports
- 646
- Reporting signal score
- 509.018
- Event
- arthralgia
- Reports
- 1,414
- Reporting signal score
- 795.511
- Event
- bone lesion
- Reports
- 72
- Reporting signal score
- 161.889
- Event
- bone pain
- Reports
- 500
- Reporting signal score
- 585.225
- Event
- breast cancer
- Reports
- 747
- Reporting signal score
- 1,391.56
- Event
- breast cancer metastatic
- Reports
- 706
- Reporting signal score
- 2,438.56
- Event
- breast cancer recurrent
- Reports
- 219
- Reporting signal score
- 657.867
- Event
- carbohydrate antigen 15-3 increased
- Reports
- 99
- Reporting signal score
- 371.326
- Event
- disease progression
- Reports
- 792
- Reporting signal score
- 777.549
- Event
- fatigue
- Reports
- 1,457
- Reporting signal score
- 271.366
- Event
- hot flush
- Reports
- 583
- Reporting signal score
- 833.928
- Event
- leukopenia
- Reports
- 288
- Reporting signal score
- 268.802
- Event
- malignant neoplasm progression
- Reports
- 1,697
- Reporting signal score
- 3,458.5
- Event
- metastases to bone
- Reports
- 950
- Reporting signal score
- 2,829.77
- Event
- metastases to liver
- Reports
- 751
- Reporting signal score
- 2,074.1
- Event
- metastases to lung
- Reports
- 361
- Reporting signal score
- 878.689
- Event
- metastases to lymph nodes
- Reports
- 279
- Reporting signal score
- 718.928
- Event
- metastases to skin
- Reports
- 58
- Reporting signal score
- 186.183
- Event
- metastases to spine
- Reports
- 119
- Reporting signal score
- 318.403
- Event
- neoplasm progression
- Reports
- 783
- Reporting signal score
- 1,678.37
- Event
- neutropenia
- Reports
- 1,390
- Reporting signal score
- 1,407.43
- Event
- pik3ca-activated mutation
- Reports
- 95
- Reporting signal score
- 399.317
- Event
- second primary malignancy
- Reports
- 158
- Reporting signal score
- 259.77
- Event
- tumour marker increased
- Reports
- 166
- Reporting signal score
- 418.476
- Event
- white blood cell count decreased
- Reports
- 318
- Reporting signal score
- 187.282
- NCT00003140
- NCT00004205
- NCT00014638
- NCT00084396
- NCT00090857
- NCT00101062
- NCT00107263
- NCT00134680
- NCT00161291
- NCT00171314
- NCT00171704
- NCT00171847
- NCT00194779
- NCT00199134
- NCT00208273
- NCT00237133
- NCT00237224
- NCT00238290
- NCT00238316
- NCT00241046
- NCT00247650
- NCT00248170
- NCT00265759
- NCT00280930
- NCT00290745
And 302 more, listed on the interactive page.
- Dose
- 2.5mg
- Route
- Oral
- How often
- Once daily
- Hydrogen bond acceptors
- 5
- Hydrogen bond donors
- 0
- Polar surface area
- 78.29
- Calculated partition coefficient (ALogP)
- 2.66
- Calculated partition coefficient (XLogP)
- 2.7
- Prodrug
- No
- Chirality
- Achiral
- Inorganic
- No
- Rule-of-five violations
- 0
- Rotatable bonds
- 3
- Heavy atoms
- 22
- Molecular formula
- C17H11N5
- Monoisotopic mass
- 285.10144537
- Natural product
- Yes
- 0078-0249
- 0093-7620
- 16729-034
- 23155-875
- 24979-726
- 42291-374
- 50268-476
- 51407-986
- 51991-759
- 55111-646
- 59651-180
- 62135-491
- 71205-587
- 80005-139
- 17856-0032
- 50090-3474
- 50090-8002
- 63629-7819
- 63850-0025
- 68071-2167
- 68071-5264
- 69117-0004
- 71335-1526
- 71335-2396
- Recorded assays
- 2,570
- Active assays
- 116
- Confirmatory
- Other
- Screening
- Summary
- Antineoplastic Agents
- Aromatase Inhibitors
Oral bioavailability
- Median
- 99.9
- Mean
- 99.9
- Minimum
- 99.9
- Maximum
- 99.9
- Unit
- %
- Assays
- 1
- Standard deviation
- 0
- Summary method
- median
- Censored results excluded
- 0
- Other units excluded
- 0
- Unknown units excluded
- 0
Measurement types
- F
Related records
Trials (756)
- A 2-Week Ketogenic Diet in Combination With Letrozole to Modulate PI3K Signaling in ER+ Breast Cancer
- A 5-treatment, Study in Healthy Volunteers to Assess The Safety, Tolerability, and Pharmacokinetics of Four Controlled Release (CR) Pregabalin Tablet Formulations and the Immediate Release (IR) Formulation Administered Fasted
- A Clinical Study of Darcilil Combined With AI Combined With Pyrrotinib in the Treatment of TPBC
- A Clinical Study of HRS-6209 Combined With Other Treatment Regimens in Patients With Breast Cancer
- A Clinical Study to Evaluate the Safety and Efficacy of JHM03 in Adult Patients With Upper Limb Spasticity
- A Clinical Trial to Compare Efficacy and Tolerability of Atorvastatin in Addition to Endocrine Treatment With Focus on Mechanisms of Resistance to Endocrine Treatment (Fulvestrant/Aromatase Inhibitors) in Patients With Advanced Breast Cancer
- A Companion Sample Collection Protocol to Support the Discovery of Breast Cancer Aberrations With Treatment of CDK4/6 Therapy/LEE011/Ribociclib
- A Comparison of Letrozole and Clomifene Citrate
- A Dose Escalation Study Evaluating the Safety and Tolerability of GDC-0032 in Participants With Locally Advanced or Metastatic Solid Tumors or Non-Hodgkin's Lymphoma (NHL) and in Combination With Endocrine Therapy in Locally Advanced or Metastatic Hormone Receptor-Positive Breast Cancer
- A New Oral Treatment For Type II Diabetes Mellitus
- A Open Study of Metronomic Oral Vinorelbine in Combination With Aromatase Inhibitors for the Treatment of Postmenopausal Women With Hormone Receptor Positive,HER2-negative, Advanced Breast Cancer Who Received no Prior Therapy for Advanced Disease
- A Pharmacodynamics Pre-surgical Study of LEE011 in Early Breast Cancer Patients (MONALEESA-1)
- A Phase 2 Single-Arm Open-Label Pilot Trial Evaluating Zanidatamab (ZW25) in Patients With Early Stage HER2/Neu Positive (HER2+) Breast Cancer (BC)
- A Phase 3 Study of HRS-8080 Versus Treatment Chosen by Physicians in Locally Advanced and Metastatic Breast Cancer
- A Phase I/II Study of XZP-3287 in Metastasis Solid Tumors
- A Phase Ib Dose Escalation Study of the Combination of LEE011 With Letrozole and Dose Expansion of LEE011 With Hormonal Therapy for the Treatment of Pre-(With Goserelin) and Postmenopausal Women With Hormone Receptor Positive, HER2-negative, Advanced Breast Cancer
- A Phase Ib Study of GB491 Plus Letrozole in Patients With Advanced Breast Cancer
- A Phase II Clinical Study to Evaluate HLX43 in Subjects With Advanced Non-small Cell Lung Cancer (NSCLC)
- A Phase II Clinical Study to Evaluate HLX43 in Subjects With Advanced Pancreatic Cancer
- A Phase II Randomized Study Evaluating the Biological and Clinical Effects of the Combination of Palbociclib With Letrozole as Neoadjuvant Therapy in Post-Menopausal Women With Estrogen-Receptor Positive Primary Breast Cancer
Approved for (5)
- Breast cancer
- Breast carcinoma
- Breast neoplasm
- Cancer
- Neoplasm
In development for (43)
- Adenomyosis Phase 2
- Angiosarcoma Phase 2
- Anovulation Phase 2
- Brain neoplasm Early phase 1
- Breast lobular carcinoma Phase 2
- Carcinoma Phase 2
- Cervical adenocarcinoma Phase 2
- Ductal breast carcinoma in situ Phase 3
- Ectopic pregnancy Phase 1
- Endometrial cancer Phase 3
- Endometrial carcinoma Phase 3
- Endometrioid adenocarcinoma Phase 1
- Endometriosis Phase 2
- Fallopian tube cancer Phase 2
- Fallopian tube carcinoma Phase 2
- Female breast carcinoma Phase 3
- Hereditary breast ovarian cancer syndrome Phase 3
- Hermansky-Pudlak syndrome Phase 2
- Hypogonadotropic hypogonadism Phase 3
- Infertility disorder Phase 3
Other linked conditions (3)
- Estrogen-receptor positive breast cancer
- Gestational trophoblastic neoplasm
- Habitual spontaneous abortion
Targets (1)
- CYP19A1 Cytochrome P450 19A1 inhibitor