Testolactone 50mg tablets
Requires a prescription from a doctor or prescriber
An antineoplastic agent that is a derivative of progesterone and used to treat advanced breast cancer.
Official documents, adverse reaction reporting, and safety monitoring
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Safety monitoring data
Yellow Card reports
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Data from the MHRA Yellow Card scheme. A reported reaction does not necessarily mean the medicine caused it. Contains public sector information licensed under the Open Government Licence v3.0.
EudraVigilance
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1 branded products available
NHS prescribing volume and spending trends
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Supply & safety information
Official UK regulator monitoring and safety alerts
Pharmacy links redirect to the retailer's own search and do not represent real-time stock levels. Shortage and safety information sourced from MHRA drug safety updates (gov.uk, Crown Copyright under OGL v3.0).
Codes for healthcare professionals and prescribing systems
These codes are used by healthcare IT systems and prescribers to identify this medicine.
NHS UK identifiers
SNOMED CT and dm+d codes from NHS TRUD (Technology Reference data Update Distribution), licensed under the Open Government Licence v3.0.
Active and completed clinical studies from ClinicalTrials.gov
Source: ClinicalTrials.gov, a database of the U.S. National Library of Medicine (NLM), National Institutes of Health (NIH). Data accessed via ClinicalTrials.gov API v2. Trial information is provided for research purposes and does not constitute medical advice.
Academic studies and reviews for this medicine's active substance
Showing the 50 most relevant studies.
Randomised trials: 1 · 1970–2024
Showing the 50 most relevant studies, sorted by most relevant.
Richard V. Clark, Richard J. Sherins
Journal of Andrology, 1989
- Aromatase
- Clinical Trials as Topic
- Estradiol
Deborah P. Merke, Margaret F. Keil, Janet V. Jones, et al.
The Journal of Clinical Endocrinology & Metabolism, 2000
- Adrenal Hyperplasia, Congenital
- Androgen Antagonists
- Androgens
William R. Waddell, Wolff M. Kirsch
The American Journal of Surgery, 1991
- Abdominal Neoplasms
- Antineoplastic Combined Chemotherapy Protocols
- Fibroma
Louisa Laue, Daniel Kenigsberg, Ora Hirsch Pescovitz, et al.
New England Journal of Medicine, 1989
- Aggression
- Body Height
- Depression, Chemical
Barnett Zumoff, Lorraine K. Miller, Gladys Strain
Metabolism, 2003
- Aromatase Inhibitors
- Enzyme Inhibitors
- Estradiol
P. P. Feuillan, C. Foster, Ora Hirsch Pescovitz, et al.
New England Journal of Medicine, 1986
- Bone Development
- Estradiol
- Estrone
Marina Savic, Ivana Kuzminac, Andrea Nikolic
Drugs and Drug Candidates, 2023
Testolactone is structurally related to testosterone and belongs to the first generation of aromatase inhibitors. It is a non-selective irreversible aromatase enzyme inhibitor that was one of the first steroids used in the clinical treatment of breast cancer. The use of testolactone in the treatment of breast cancer started in 1970, although its ability to inhibit aromatase was not discovered until 1975. Its use was primarily based on the inhibition of estrogen synthesis, which was applied in the treatment of estrogen-dependent breast cancers, in the treatment of disorders of sex steroid excess, familial male-limited precocious puberty, or in the treatment of patients with McCune–Albright syndrome, etc. The weak inhibitory activity of testolactone, and the moderate clinical response, prevented its widespread use, which ultimately resulted in withdrawal from the drug market in 2008. This review paper is dedicated to testolactone, its rise in the second half of the 20th century, and its fall in the first decade of the 21st century. Regardless of withdrawal from the market, for many years testolactone was a drug that improved the quality of life of patients facing one of the most serious diseases today, and for this reason, this paper describes medicinal application, synthesis, and modifications of testolactone.
Abstract licence: CC BY 4.0
Andrew G. Herzog, Pavel Klein, Alan R. Jacobs
Neurology, 1998
- Enzyme Inhibitors
- Epilepsy
- Estradiol
Penelope Feuillan, J. Jones, Gordon B. Cutler
The Journal of Clinical Endocrinology & Metabolism, 1993
- Age Determination by Skeleton
- Androstenedione
- Body Height
Xinqi Xu, Jinchang Zhong, Bingmei Su, et al.
International Journal of Biological Macromolecules, 2024
- Mixed Function Oxygenases
- Escherichia coli
- Ketones
Sources: aggregated from Europe PMC (EMBL-EBI), OpenAlex, Crossref, PubMed and other open scholarly databases. Retracted articles are excluded. Study information is provided for research purposes and does not constitute medical advice.
Pharmacology and chemical data from DrugBank
Key facts
Drug status
Approved
Major interactions
None known
Half-life
Not available
Mechanism
Although the precise mechanism by which testolactone produces its clinical antin…
Food interactions
None known
Human targets
1 target
Data: DrugBank · CC BY-NC 4.0
Pharmacokinetics at a glance
Absorption
Protein binding
85%
Metabolism
Elimination
150 mg/d
Pharmacokinetic data: DrugBank · CC BY-NC 4.0
Known interactions with other medicines. Always consult a healthcare professional.
Showing 50 of 765 interactions
How the body processes this drug — absorption, distribution, metabolism, and elimination
Proteins and enzymes this drug interacts with in the body
PMID:27702664 PMID:2848247
Catalyzes three successive oxidations of C19 androgens: two conventional oxidations at C19 yielding 19-hydroxy and 19-oxo/19-aldehyde derivatives, followed by a third oxidative aromatization step that involves C1-beta hydrogen abstraction combined with cleavage of the C10-C19 bond to yield a phenolic A ring and formic acid .
PMID:20385561
Alternatively, the third oxidative reaction yields a 19-norsteroid and formic acid. Converts dihydrotestosterone to delta1,10-dehydro 19-nordihydrotestosterone and may play a role in homeostasis of this potent androgen .
PMID:22773874
Also displays 2-hydroxylase activity toward estrone .
PMID:22773874
Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (CPR; NADPH-ferrihemoprotein reductase) PMID:20385561 PMID:22773874
Chemical identifiers
CAS, UNII, InChI Key and database cross-references
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Chemical identifiers
CAS, UNII, InChI Key and database cross-references
Linked compound data from DrugBank Open Data (CC BY-NC 4.0)
Testolactone
Additional database identifiers
ChemSpider
13172
BindingDB
50367848
ZINC
ZINC000004081771
HUGO Gene Nomenclature Committee (HGNC)
HGNC:2594
GenAtlas
CYP19A1
GeneCards
CYP19A1
GenBank Gene Database
M22246
GenBank Protein Database
179002
Guide to Pharmacology
1362
UniProt Accession
CP19A_HUMAN
DrugBank citations
If you use DrugBank data in your research, please cite:
- DrugBank 6.02024Recommended citationKnox C., Wilson M., Klinger C.M., et alDrugBank 6.0: the DrugBank Knowledgebase for 2024Nucleic Acids Res. 2024 Jan 552(D1):D1265-D1275
- DrugBank 5.02018Wishart D.S., Feunang Y.D., Guo A.C., et alDrugBank 5.0: a major update to the DrugBank database for 2018Nucleic Acids Res. 2017 Nov 846(D1):D1074-D1082
- DrugBank 4.02014Law V., Knox C., Djoumbou Y., et alDrugBank 4.0: shedding new light on drug metabolismNucleic Acids Res. 2014 Jan 142(1):D1091-7
- DrugBank 3.02011Knox C., Law V., Jewison T., et alDrugBank 3.0: a comprehensive resource for 'omics' research on drugsNucleic Acids Res. 2011 Jan39(Database issue):D1035-41
- DrugBank 2.02008Wishart D.S., Knox C., Guo A.C., et alDrugBank: a knowledgebase for drugs, drug actions and drug targets.Nucleic Acids Research2008 Jan36(Database issue):D901-6
- DrugBank 1.02006Wishart D.S., Knox C., Guo A.C., et alDrugBank: a comprehensive resource for in silico drug discovery and exploration.Nucleic Acids Research2006 Jan 134(Database issue):D668-72