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.
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Safety monitoring data
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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.
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1 branded products available
Therapeutically similar medicines
Similarity is based on WHO Anatomical Therapeutic Chemical (ATC) classification and on a factual NHS dm+d therapeutic-grouping code prefix. Source data: NHS dm+d via TRUD (OGL v3.0), WHO ATC/DDD Index.
NHS prescribing volume and spending trends
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Supply & safety information
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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. BNF code shown is the factual mapping value distributed by NHS Business Services Authority (NHSBSA) in the dm+d supplementary file under OGL v3.0; it is not affiliated with, nor licensed from, the publishers of the British National Formulary.
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 all 12 studies.
Reviews & meta-analyses: 2 · Randomised trials: 1 · 1986–2024
Showing all 12 studies, sorted by most relevant.
Del Giudice F, Busetto GM, De Berardinis E, et al.
2020
- Letrozole
- Anastrozole
- Clinical Trials as Topic
Aromatase activity has commonly been associated with male infertility characterized by testicular dysfunction with low serum testosterone and/or testosterone to estradiol ratio. In this subset of patients, and particularly in those with hypogonadism, elevated levels of circulating estradiol may establish a negative feedback on the hypothalamic-pituitary-testicular axis by suppressing follicle-stimulating hormone (FSH) and luteinizing hormone (LH) production and impaired spermatogenesis. Hormonal manipulation via different agents such as selective estrogen modulators or aromatase inhibitors to increase endogenous testosterone production and improve spermatogenesis in the setting of infertility is an off-label option for treatment. We carried out a systematic review and meta-analysis of the literature of the past 30 years in order to evaluate the benefits of the use of aromatase inhibitors in the medical management of infertile/hypoandrogenic males. Overall, eight original articles were included and critically evaluated. Either steroidal (Testolactone) or nonsteroidal (Anastrozole and Letrozole) aromatase inhibitors were found to statistically improve all the evaluated hormonal and seminal outcomes with a safe tolerability profile. While the evidence is promising, future prospective randomized placebo-controlled multicenter trials are necessary to better define the efficacy of these medications.
Abstract licence: CC BY-NC-SA
Richard V. Clark, R. Sherins
Journal of andrology, 1989
- Aromatase
- Clinical Trials as Topic
- Estradiol
D. Merke, M. Keil, Janet Jones, et al.
The Journal of clinical endocrinology and metabolism, 2000
- Adrenal Hyperplasia, Congenital
- Androgen Antagonists
- Androgens
Marina P. Savić, I. Kuzminac, Andrea R. Nikolić
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
W. Waddell, Wolff M. Kirsch
American journal of surgery, 1991
- Abdominal Neoplasms
- Antineoplastic Combined Chemotherapy Protocols
- Fibroma
B. Zumoff, L. Miller, G. Strain
Metabolism: clinical and experimental, 2003
- Aromatase Inhibitors
- Enzyme Inhibitors
- Estradiol
L. Laue, D. Kenigsberg, O. Pescovitz, et al.
The New England journal of medicine, 1989
- Aggression
- Body Height
- Depression, Chemical
A. Herzog, P. Klein, A. Jacobs
Neurology, 1998
- Enzyme Inhibitors
- Epilepsy
- Estradiol
E. Leschek, Janet Jones, K. Barnes, et al.
The Journal of clinical endocrinology and metabolism, 1999
- Bone Development
- Growth
- Gonadotropin-Releasing Hormone
P. Feuillan, Janet Jones, G. Cutler
The Journal of clinical endocrinology and metabolism, 1993
- Age Determination by Skeleton
- Androstenedione
- Body Height
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 medications. 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
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Structured knowledge from the free knowledge base
Linked open data from Wikidata (Q3985253), a free and open knowledge base operated by the Wikimedia Foundation. Data is available under the Creative Commons CC0 1.0 Public Domain Dedication.