Formestane

Identification

Name
Formestane
Accession Number
DB08905
Type
Small Molecule
Groups
Approved, Investigational, Withdrawn
Description

Formestane was the first selective, type I, steroidal aromatase inhibitor used in the treatment of estrogen-receptor positive breast cancer in post-menopausal women. Formestane suppresses estrogen production from anabolic steroids or prohormones. It also acts as a prohormone to 4-hydroxytestosterone, an active steroid which displays weak androgenic activity in addition to acting as a mild aromatase inhibitor. It is listed as a prohibited substance by the World Anti-Doping Agency for use in athletes.

Formestane has poor oral bioavailability, and thus must be administered forthnightly (bi-weekly) by intramuscular injection. Some clinical data has suggested that the clinically recommended dose of 250mg was too low. With the discovery of newer, non-steroidal and steroidal, aromatase inhibitors which were orally active and less expensive than formestane, formestane lost popularity.

Currently, formestane (categorized as an anti-estrogenic agent) is prohibited from use in sports in accordance to the regulations of the World Anti-Doping Agency. It is not US FDA approved, and the intramuscular injection form of formestane (Lentaron) which was approved in Europe has been withdrawn.

Structure
Thumb
Synonyms
  • 4-hydroxy-4-androstene-3,17-dione
  • 4-Hydroxy-delta(4)-androstenedione
  • 4-hydroxy-Δ4-androstenedione
  • 4-hydroxyandrostenedione
  • 4-OH-A
  • 4-OHAD
  • Formestano
  • Formestanum
External IDs
CGP 32349 / CGP-32349
Product Ingredients
Not Available
Approved Prescription Products
Not Available
Approved Generic Prescription Products
Not Available
Approved Over the Counter Products
Not Available
Unapproved/Other Products
Not Available
International/Other Brands
Lentaron
Brand mixtures
NameIngredientsDosageRouteLabellerMarketing StartMarketing End
LentaronLiquid; Powder, for solutionIntramuscularNovartis1994-12-311999-08-04Canada
Categories
UNII
PUB9T8T355
CAS number
566-48-3
Weight
Average: 302.4079
Monoisotopic: 302.188194698
Chemical Formula
C19H26O3
InChI Key
OSVMTWJCGUFAOD-KZQROQTASA-N
InChI
InChI=1S/C19H26O3/c1-18-10-8-15(20)17(22)14(18)4-3-11-12-5-6-16(21)19(12,2)9-7-13(11)18/h11-13,22H,3-10H2,1-2H3/t11-,12-,13-,18+,19-/m0/s1
IUPAC Name
(1S,2R,10R,11S,15S)-6-hydroxy-2,15-dimethyltetracyclo[8.7.0.0²,⁷.0¹¹,¹⁵]heptadec-6-ene-5,14-dione
SMILES
[H][[email protected]@]12CCC(=O)[[email protected]@]1(C)CC[[email protected]@]1([H])[[email protected]@]2([H])CCC2=C(O)C(=O)CC[[email protected]]12C

Pharmacology

Indication

For the treatment of estrogen-receptor positive breast cancer in post-menopausal women.

Structured Indications
Not Available
Pharmacodynamics

By significantly reducing estrogen levels in the bloodstream, formestane may exhibit antitumor activity.

In one trial involving 147 postmenopausal females with advanced breast cancers resistant to standard therapies, 22% of patients achieved a partial response, while another 20% achieved disease stabilization. [3]

In comparative trials comparing a non-steroidal aromatase inhibitor, anastrozole, with formestane, it was found that anastrozole was more effective and consistent at suppressing estrogen levels in the body. However, these results were of unverified clinical significance. [5]

Mechanism of action

Formestane is a second generation, irreversible, steroidal aromatase inhibitor. It inhibits the aromatase enzyme responsible for converting androgens to estrogens, thereby preventing estrogen production.

Breast cancer may be estrogen sensitive or insensitive. A majority of breast cancers are estrogen sensitive. Estrogen sensitive breast cancer cells depend on estrogen for viability. Thus removal of estrogen from the body can be an effective treatment for hormone sensitive breast cancers.

Formestane has been targeted specifically for the treatment of postmenopausal women. Unlike premenopausal women who produce most estrogen in the ovaries, postmenopausal women produce most estrogen in peripheral tissues with the help of the aromatase enzyme. Formestane, an aromatase inhibitor, can thus help to decrease the local production of estrogen by blocking the aromatase enzyme in peripheral tissues (ie. adispose tissue of the breast) to treat hormone sensitive breast cancer.

Absorption

Formestane has poor oral bioavailability, but is fully bioavailable when administered via the established intramuscular route. The AUC after an intravenous pulse dose does not vary considerably from that of an intramuscular dose.

Within 24-48 h of the first dose of intramuscular formestane, a C(max) of 48.0 +/- 20.9 nmol/l was achieved in one study. [2]

Volume of distribution

Vd = 1.8 L/kg; widely distributed to organs and tissues when delivered intravenously. [2]

Protein binding
Not Available
Metabolism

Hepatic metabolism. Phase I of metabolism is mainly reductive in nature. The reduction products 3 beta-hydroxy-5alpha-androstane-4,17-dione and 3alpha-hydroxy-5beta-androstane-4,17-dione are produced, and further reduced. A notable step in the process of metabolism is a keto reduction on carbon number three of the molecule. The main metabolite which is produced from formestane is 4-hydroyxyandrost-4-ene-3,17-dione-4-glucuronide.

The oxidation products identified were 4-hydroxyandrosta-4,6-diene-3,17-dione and 4-hydroxyandrosta-1,4-diene-3,17-dione.

In phase II, conjugation was diverse and included sulfatation and glucuronidation. 4-hydroxytestosterone, the 17-hydroxylated analog to formestane, was identified as one particular metabolite found in women's urine. This finding was the result of an oral administration of 500mg of formestane in women.

Route of elimination

Renal elimination. >95% in urine, <5% in feces.

Half life

Terminal plasma elimination half life of 18 minutes, when delivered intravenously. [2]

Clearance

Plasma clearance is approximately 4.2 L/(h kg), when delivered intravenously.

In women, following a 500mg dose of formestane, 20% was excreted as glucuronide within the first 24 hours. [1]

One long term metabolite (3beta,4alpha-dihydroxy-5alpha-androstan-17-one) can be detected for 90 hours. A longer detection time is possible with more sensitive technology, which may be of utility in sports drug testing. [1]

Toxicity
Not Available
Affected organisms
Not Available
Pathways
Not Available
Pharmacogenomic Effects/ADRs
Not Available

Interactions

Drug Interactions
DrugInteractionDrug group
1,10-PhenanthrolineThe risk or severity of adverse effects can be increased when Formestane is combined with 1,10-Phenanthroline.Experimental
AceclofenacThe risk or severity of adverse effects can be increased when Aceclofenac is combined with Formestane.Approved
AcetyldigitoxinAcetyldigitoxin may decrease the cardiotoxic activities of Formestane.Approved
Acetylsalicylic acidThe risk or severity of adverse effects can be increased when Acetylsalicylic acid is combined with Formestane.Approved, Vet Approved
AdapaleneThe risk or severity of adverse effects can be increased when Adapalene is combined with Formestane.Approved
AldesleukinFormestane may decrease the antineoplastic activities of Aldesleukin.Approved
Aluminum hydroxideThe bioavailability of Formestane can be decreased when combined with Aluminum hydroxide.Approved
AmbenoniumThe risk or severity of adverse effects can be increased when Formestane is combined with Ambenonium.Approved
Aminosalicylic AcidThe risk or severity of adverse effects can be increased when Aminosalicylic Acid is combined with Formestane.Approved
AmiodaroneThe serum concentration of Formestane can be increased when it is combined with Amiodarone.Approved, Investigational
Amphotericin BFormestane may increase the hypokalemic activities of Amphotericin B.Approved, Investigational
AndrographolideThe risk or severity of adverse effects can be increased when HMPL-004 is combined with Formestane.Investigational
AnisodamineThe risk or severity of adverse effects can be increased when Anisodamine is combined with Formestane.Investigational
AntipyrineThe risk or severity of adverse effects can be increased when Antipyrine is combined with Formestane.Approved
ApocyninThe risk or severity of adverse effects can be increased when Acetovanillone is combined with Formestane.Investigational
ApremilastThe risk or severity of adverse effects can be increased when Apremilast is combined with Formestane.Approved, Investigational
AprepitantThe serum concentration of Formestane can be increased when it is combined with Aprepitant.Approved, Investigational
AtazanavirThe serum concentration of Formestane can be increased when it is combined with Atazanavir.Approved, Investigational
Atracurium besylateAtracurium besylate may increase the adverse neuromuscular activities of Formestane.Approved
AzapropazoneThe risk or severity of adverse effects can be increased when Azapropazone is combined with Formestane.Withdrawn
AzelastineThe risk or severity of adverse effects can be increased when Azelastine is combined with Formestane.Approved
BalsalazideThe risk or severity of adverse effects can be increased when Balsalazide is combined with Formestane.Approved, Investigational
BazedoxifeneThe serum concentration of Formestane can be increased when it is combined with Bazedoxifene.Approved, Investigational
BendroflumethiazideFormestane may increase the hypokalemic activities of Bendroflumethiazide.Approved
BenoxaprofenThe risk or severity of adverse effects can be increased when Benoxaprofen is combined with Formestane.Withdrawn
Benzoic AcidThe therapeutic efficacy of Benzoic Acid can be decreased when used in combination with Formestane.Approved
Betulinic AcidThe risk or severity of adverse effects can be increased when Betulinic Acid is combined with Formestane.Investigational
BevacizumabBevacizumab may increase the cardiotoxic activities of Formestane.Approved, Investigational
Bismuth SubcitrateThe bioavailability of Formestane can be decreased when combined with Bismuth Subcitrate.Approved
BoceprevirThe serum concentration of Formestane can be increased when it is combined with Boceprevir.Withdrawn
BromfenacThe risk or severity of adverse effects can be increased when Bromfenac is combined with Formestane.Approved
BucillamineThe risk or severity of adverse effects can be increased when Bucillamine is combined with Formestane.Investigational
BumetanideFormestane may increase the hypokalemic activities of Bumetanide.Approved
CabazitaxelThe risk or severity of adverse effects can be increased when Cabazitaxel is combined with Formestane.Approved
CalcitriolThe therapeutic efficacy of Calcitriol can be decreased when used in combination with Formestane.Approved, Nutraceutical
Calcium CarbonateThe bioavailability of Formestane can be decreased when combined with Calcium carbonate.Approved
CarbamazepineThe serum concentration of Formestane can be decreased when it is combined with Carbamazepine.Approved, Investigational
CarprofenThe risk or severity of adverse effects can be increased when Carprofen is combined with Formestane.Approved, Vet Approved, Withdrawn
CastanospermineThe risk or severity of adverse effects can be increased when Castanospermine is combined with Formestane.Experimental
CelecoxibThe risk or severity of adverse effects can be increased when Celecoxib is combined with Formestane.Approved, Investigational
CeritinibFormestane may increase the hyperglycemic activities of Ceritinib.Approved
ChloroquineThe risk or severity of adverse effects can be increased when Chloroquine is combined with Formestane.Approved, Vet Approved
ChlorothiazideFormestane may increase the hypokalemic activities of Chlorothiazide.Approved, Vet Approved
ChlorotrianiseneThe serum concentration of Formestane can be increased when it is combined with Chlorotrianisene.Withdrawn
ChlorthalidoneFormestane may increase the hypokalemic activities of Chlorthalidone.Approved
CholestyramineCholestyramine can cause a decrease in the absorption of Formestane resulting in a reduced serum concentration and potentially a decrease in efficacy.Approved
Choline magnesium trisalicylateThe risk or severity of adverse effects can be increased when Trisalicylate-choline is combined with Formestane.Approved
CinoxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Cinoxacin.Approved, Withdrawn
CiprofloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Ciprofloxacin.Approved, Investigational
ClarithromycinThe serum concentration of Formestane can be increased when it is combined with Clarithromycin.Approved
ClonixinThe risk or severity of adverse effects can be increased when Clonixin is combined with Formestane.Approved
CobicistatThe serum concentration of Formestane can be increased when it is combined with Cobicistat.Approved
ColesevelamColesevelam can cause a decrease in the absorption of Formestane resulting in a reduced serum concentration and potentially a decrease in efficacy.Approved
ColestipolColestipol can cause a decrease in the absorption of Formestane resulting in a reduced serum concentration and potentially a decrease in efficacy.Approved
Conjugated estrogensThe serum concentration of Formestane can be increased when it is combined with Conjugated Equine Estrogens.Approved
Corticorelin ovine triflutateThe therapeutic efficacy of Corticorelin ovine triflutate can be decreased when used in combination with Formestane.Approved
CoumaphosThe risk or severity of adverse effects can be increased when Formestane is combined with Coumaphos.Vet Approved
CurcuminThe risk or severity of adverse effects can be increased when Curcumin is combined with Formestane.Investigational
CyclophosphamideCyclophosphamide may increase the cardiotoxic activities of Formestane.Approved, Investigational
D-LimoneneThe risk or severity of adverse effects can be increased when D-Limonene is combined with Formestane.Investigational
DarunavirThe serum concentration of Formestane can be increased when it is combined with Darunavir.Approved
DecamethoniumThe risk or severity of adverse effects can be increased when Formestane is combined with Decamethonium.Approved
DeferasiroxThe risk or severity of adverse effects can be increased when Formestane is combined with Deferasirox.Approved, Investigational
DemecariumThe risk or severity of adverse effects can be increased when Formestane is combined with Demecarium.Approved
dersalazineThe risk or severity of adverse effects can be increased when dersalazine is combined with Formestane.Investigational
DeslanosideDeslanoside may decrease the cardiotoxic activities of Formestane.Approved
DichlorvosThe risk or severity of adverse effects can be increased when Formestane is combined with Dichlorvos.Vet Approved
DiclofenacThe risk or severity of adverse effects can be increased when Diclofenac is combined with Formestane.Approved, Vet Approved
DienestrolThe serum concentration of Formestane can be increased when it is combined with Dienestrol.Approved
DiethylstilbestrolThe serum concentration of Formestane can be increased when it is combined with Diethylstilbestrol.Approved
DiflunisalThe risk or severity of adverse effects can be increased when Diflunisal is combined with Formestane.Approved
DigitoxinDigitoxin may decrease the cardiotoxic activities of Formestane.Approved
DigoxinDigoxin may decrease the cardiotoxic activities of Formestane.Approved
DihydrotestosteroneFormestane may increase the fluid retaining activities of Dihydrotestosterone.Illicit
DocetaxelThe risk or severity of adverse effects can be increased when Docetaxel is combined with Formestane.Approved, Investigational
DonepezilThe risk or severity of adverse effects can be increased when Formestane is combined with Donepezil.Approved
DroxicamThe risk or severity of adverse effects can be increased when Droxicam is combined with Formestane.Approved
DuvelisibThe risk or severity of adverse effects can be increased when Duvelisib is combined with Formestane.Investigational
E-6201The risk or severity of adverse effects can be increased when E6201 is combined with Formestane.Investigational
EbselenThe risk or severity of adverse effects can be increased when Ebselen is combined with Formestane.Investigational
EchothiophateThe risk or severity of adverse effects can be increased when Formestane is combined with Echothiophate.Approved
EdrophoniumThe risk or severity of adverse effects can be increased when Formestane is combined with Edrophonium.Approved
EnoxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Enoxacin.Approved
EnzalutamideThe serum concentration of Formestane can be decreased when it is combined with Enzalutamide.Approved
EpirizoleThe risk or severity of adverse effects can be increased when Epirizole is combined with Formestane.Approved
EquolThe serum concentration of Formestane can be increased when it is combined with S Equol.Investigational
EstradiolThe serum concentration of Formestane can be increased when it is combined with Estradiol.Approved, Investigational, Vet Approved
EstriolThe serum concentration of Formestane can be increased when it is combined with Estriol.Approved, Vet Approved
EstroneThe serum concentration of Formestane can be increased when it is combined with Estrone.Approved
Etacrynic acidFormestane may increase the hypokalemic activities of Etacrynic acid.Approved
EtanerceptThe risk or severity of adverse effects can be increased when Etanercept is combined with Formestane.Approved, Investigational
Ethinyl EstradiolThe serum concentration of Formestane can be increased when it is combined with Ethinyl Estradiol.Approved
EtodolacThe risk or severity of adverse effects can be increased when Etodolac is combined with Formestane.Approved, Investigational, Vet Approved
EtofenamateThe risk or severity of adverse effects can be increased when Etofenamate is combined with Formestane.Approved
EtoricoxibThe risk or severity of adverse effects can be increased when Etoricoxib is combined with Formestane.Approved, Investigational
Evening primrose oilThe risk or severity of adverse effects can be increased when Evening primrose oil is combined with Formestane.Approved
exisulindThe risk or severity of adverse effects can be increased when exisulind is combined with Formestane.Investigational
FenbufenThe risk or severity of adverse effects can be increased when Fenbufen is combined with Formestane.Approved
FenoprofenThe risk or severity of adverse effects can be increased when Fenoprofen is combined with Formestane.Approved
FenthionThe risk or severity of adverse effects can be increased when Formestane is combined with Fenthion.Vet Approved
FleroxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Fleroxacin.Approved
FloctafenineThe risk or severity of adverse effects can be increased when Floctafenine is combined with Formestane.Approved, Withdrawn
FlumequineThe risk or severity of adverse effects can be increased when Formestane is combined with Flumequine.Withdrawn
FlunixinThe risk or severity of adverse effects can be increased when Flunixin is combined with Formestane.Vet Approved
FluoxymesteroneFormestane may increase the fluid retaining activities of Fluoxymesterone.Approved, Illicit
FlurbiprofenThe risk or severity of adverse effects can be increased when Flurbiprofen is combined with Formestane.Approved, Investigational
FosaprepitantThe serum concentration of Formestane can be increased when it is combined with Fosaprepitant.Approved
FosphenytoinThe serum concentration of Formestane can be decreased when it is combined with Fosphenytoin.Approved
FurosemideFormestane may increase the hypokalemic activities of Furosemide.Approved, Vet Approved
G17DTThe risk or severity of adverse effects can be increased when Formestane is combined with G17DT.Investigational
GalantamineThe risk or severity of adverse effects can be increased when Formestane is combined with Galantamine.Approved
Gallamine TriethiodideThe risk or severity of adverse effects can be increased when Formestane is combined with Gallamine Triethiodide.Approved
GarenoxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Garenoxacin.Investigational
GatifloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Gatifloxacin.Approved, Investigational
GemifloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Gemifloxacin.Approved, Investigational
GenisteinThe serum concentration of Formestane can be increased when it is combined with Genistein.Investigational
GI-5005The risk or severity of adverse effects can be increased when Formestane is combined with GI-5005.Investigational
Ginkgo bilobaThe risk or severity of adverse effects can be increased when Formestane is combined with Ginkgo biloba.Approved, Nutraceutical
Glycerol PhenylbutyrateThe therapeutic efficacy of Glycerol Phenylbutyrate can be decreased when used in combination with Formestane.Approved
GrepafloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Grepafloxacin.Withdrawn
HexestrolThe serum concentration of Formestane can be increased when it is combined with Hexestrol.Withdrawn
HigenamineThe risk or severity of adverse effects can be increased when Higenamine is combined with Formestane.Investigational
Huperzine AThe risk or severity of adverse effects can be increased when Formestane is combined with Huperzine A.Investigational
HyaluronidaseThe therapeutic efficacy of Hyaluronidase can be decreased when used in combination with Formestane.Approved, Investigational
HydrochlorothiazideFormestane may increase the hypokalemic activities of Hydrochlorothiazide.Approved, Vet Approved
HydroflumethiazideFormestane may increase the hypokalemic activities of Hydroflumethiazide.Approved
IbuprofenThe risk or severity of adverse effects can be increased when Ibuprofen is combined with Formestane.Approved
IbuproxamThe risk or severity of adverse effects can be increased when Ibuproxam is combined with Formestane.Withdrawn
IcatibantThe risk or severity of adverse effects can be increased when Icatibant is combined with Formestane.Approved
IdelalisibThe serum concentration of Formestane can be increased when it is combined with Idelalisib.Approved
IndacaterolIndacaterol may increase the hypokalemic activities of Formestane.Approved
IndapamideFormestane may increase the hypokalemic activities of Indapamide.Approved
IndinavirThe serum concentration of Formestane can be increased when it is combined with Indinavir.Approved
IndomethacinThe risk or severity of adverse effects can be increased when Indomethacin is combined with Formestane.Approved, Investigational
IndoprofenThe risk or severity of adverse effects can be increased when Indoprofen is combined with Formestane.Withdrawn
INGN 201The risk or severity of adverse effects can be increased when Formestane is combined with INGN 201.Investigational
INGN 225The risk or severity of adverse effects can be increased when Formestane is combined with INGN 225.Investigational
IsoflurophateThe risk or severity of adverse effects can be increased when Formestane is combined with Isoflurophate.Approved, Withdrawn
IsoniazidThe serum concentration of Isoniazid can be decreased when it is combined with Formestane.Approved
IsoxicamThe risk or severity of adverse effects can be increased when Isoxicam is combined with Formestane.Withdrawn
ItraconazoleThe serum concentration of Formestane can be increased when it is combined with Itraconazole.Approved, Investigational
KebuzoneThe risk or severity of adverse effects can be increased when Kebuzone is combined with Formestane.Experimental
KetoconazoleThe serum concentration of Formestane can be increased when it is combined with Ketoconazole.Approved, Investigational
KetoprofenThe risk or severity of adverse effects can be increased when Ketoprofen is combined with Formestane.Approved, Vet Approved
KetorolacThe risk or severity of adverse effects can be increased when Ketorolac is combined with Formestane.Approved
LeflunomideThe risk or severity of adverse effects can be increased when Leflunomide is combined with Formestane.Approved, Investigational
LevofloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Levofloxacin.Approved, Investigational
LisofyllineThe risk or severity of adverse effects can be increased when Lisofylline is combined with Formestane.Investigational
LomefloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Lomefloxacin.Approved
LopinavirThe serum concentration of Formestane can be increased when it is combined with Lopinavir.Approved
LornoxicamThe risk or severity of adverse effects can be increased when Lornoxicam is combined with Formestane.Approved
LoxoprofenThe risk or severity of adverse effects can be increased when Loxoprofen is combined with Formestane.Approved
LumacaftorThe serum concentration of Formestane can be decreased when it is combined with Lumacaftor.Approved
LumiracoxibThe risk or severity of adverse effects can be increased when Lumiracoxib is combined with Formestane.Approved, Investigational
MagaldrateThe bioavailability of Formestane can be decreased when combined with Magaldrate.Withdrawn
Magnesium carbonateThe bioavailability of Formestane can be decreased when combined with Magnesium carbonate.Approved
Magnesium HydroxideThe bioavailability of Formestane can be decreased when combined with Magnesium hydroxide.Approved
Magnesium oxideThe bioavailability of Formestane can be decreased when combined with Magnesium oxide.Approved
Magnesium salicylateThe risk or severity of adverse effects can be increased when Magnesium salicylate is combined with Formestane.Approved
Magnesium TrisilicateThe bioavailability of Formestane can be decreased when combined with Magnesium Trisilicate.Approved
MalathionThe risk or severity of adverse effects can be increased when Formestane is combined with Malathion.Approved, Investigational
MasoprocolThe risk or severity of adverse effects can be increased when Masoprocol is combined with Formestane.Approved
Meclofenamic acidThe risk or severity of adverse effects can be increased when Meclofenamic acid is combined with Formestane.Approved, Vet Approved
Mefenamic acidThe risk or severity of adverse effects can be increased when Mefenamic acid is combined with Formestane.Approved
MefloquineThe risk or severity of adverse effects can be increased when Formestane is combined with Mefloquine.Approved
MeloxicamThe risk or severity of adverse effects can be increased when Meloxicam is combined with Formestane.Approved, Vet Approved
MemantineThe risk or severity of adverse effects can be increased when Formestane is combined with Memantine.Approved, Investigational
MesalazineThe risk or severity of adverse effects can be increased when Mesalazine is combined with Formestane.Approved
MestranolThe serum concentration of Formestane can be increased when it is combined with Mestranol.Approved
MetamizoleThe risk or severity of adverse effects can be increased when Metamizole is combined with Formestane.Withdrawn
MethadoneThe serum concentration of Methadone can be increased when it is combined with Formestane.Approved
MethallenestrilThe serum concentration of Formestane can be increased when it is combined with Methallenestril.Experimental
Methanesulfonyl FluorideThe risk or severity of adverse effects can be increased when Formestane is combined with Methanesulfonyl Fluoride.Investigational
MethyclothiazideFormestane may increase the hypokalemic activities of Methyclothiazide.Approved
MethyltestosteroneFormestane may increase the fluid retaining activities of Methyltestosterone.Approved
MetolazoneFormestane may increase the hypokalemic activities of Metolazone.Approved
MifepristoneThe therapeutic efficacy of Formestane can be decreased when used in combination with Mifepristone.Approved, Investigational
MinaprineThe risk or severity of adverse effects can be increased when Formestane is combined with Minaprine.Approved
MitotaneThe serum concentration of Formestane can be decreased when it is combined with Mitotane.Approved
MivacuriumMivacurium may increase the adverse neuromuscular activities of Formestane.Approved
MizoribineThe risk or severity of adverse effects can be increased when Mizoribine is combined with Formestane.Investigational
MoxifloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Moxifloxacin.Approved, Investigational
Mycophenolate mofetilThe risk or severity of adverse effects can be increased when Mycophenolate mofetil is combined with Formestane.Approved, Investigational
Mycophenolic acidThe risk or severity of adverse effects can be increased when Mycophenolic acid is combined with Formestane.Approved
NabumetoneThe risk or severity of adverse effects can be increased when Nabumetone is combined with Formestane.Approved
NafamostatThe risk or severity of adverse effects can be increased when Nafamostat is combined with Formestane.Approved, Investigational
NaftifineThe risk or severity of adverse effects can be increased when Naftifine is combined with Formestane.Approved
Nalidixic AcidThe risk or severity of adverse effects can be increased when Formestane is combined with Nalidixic Acid.Approved
NaproxenThe risk or severity of adverse effects can be increased when Naproxen is combined with Formestane.Approved, Vet Approved
NefazodoneThe serum concentration of Formestane can be increased when it is combined with Nefazodone.Approved, Withdrawn
NelfinavirThe serum concentration of Formestane can be increased when it is combined with Nelfinavir.Approved
NemonoxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Nemonoxacin.Investigational
NeostigmineThe risk or severity of adverse effects can be increased when Formestane is combined with Neostigmine.Approved, Vet Approved
NepafenacThe risk or severity of adverse effects can be increased when Nepafenac is combined with Formestane.Approved
NevirapineThe serum concentration of Formestane can be decreased when it is combined with Nevirapine.Approved
NicorandilThe risk or severity of adverse effects can be increased when Formestane is combined with Nicorandil.Approved
Niflumic AcidThe risk or severity of adverse effects can be increased when Niflumic Acid is combined with Formestane.Approved
NimesulideThe risk or severity of adverse effects can be increased when Nimesulide is combined with Formestane.Approved, Withdrawn
NitroaspirinThe risk or severity of adverse effects can be increased when Nitroaspirin is combined with Formestane.Investigational
NorfloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Norfloxacin.Approved
OfloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Ofloxacin.Approved
OleandrinAnvirzel may decrease the cardiotoxic activities of Formestane.Experimental
OlopatadineThe risk or severity of adverse effects can be increased when Olopatadine is combined with Formestane.Approved
OlsalazineThe risk or severity of adverse effects can be increased when Olsalazine is combined with Formestane.Approved
OrgoteinThe risk or severity of adverse effects can be increased when Orgotein is combined with Formestane.Vet Approved
OuabainOuabain may decrease the cardiotoxic activities of Formestane.Approved
OxandroloneFormestane may increase the fluid retaining activities of Oxandrolone.Approved, Investigational
OxaprozinThe risk or severity of adverse effects can be increased when Oxaprozin is combined with Formestane.Approved
OxymetholoneFormestane may increase the fluid retaining activities of Oxymetholone.Approved, Illicit
OxyphenbutazoneThe risk or severity of adverse effects can be increased when Oxyphenbutazone is combined with Formestane.Withdrawn
PaclitaxelThe risk or severity of adverse effects can be increased when Paclitaxel is combined with Formestane.Approved, Vet Approved
ParecoxibThe risk or severity of adverse effects can be increased when Parecoxib is combined with Formestane.Approved
PazufloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Pazufloxacin.Investigational
PefloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Pefloxacin.Approved
PentobarbitalThe serum concentration of Formestane can be decreased when it is combined with Pentobarbital.Approved, Vet Approved
PhenobarbitalThe serum concentration of Formestane can be decreased when it is combined with Phenobarbital.Approved
Phenylacetic acidThe therapeutic efficacy of Phenylacetic acid can be decreased when used in combination with Formestane.Approved
PhenylbutazoneThe risk or severity of adverse effects can be increased when Phenylbutazone is combined with Formestane.Approved, Vet Approved
Phenylbutyric acidThe therapeutic efficacy of Sodium phenylbutyrate can be decreased when used in combination with Formestane.Approved, Investigational
PhenytoinThe serum concentration of Formestane can be decreased when it is combined with Phenytoin.Approved, Vet Approved
PhysostigmineThe risk or severity of adverse effects can be increased when Formestane is combined with Physostigmine.Approved
PimecrolimusThe risk or severity of adverse effects can be increased when Pimecrolimus is combined with Formestane.Approved, Investigational
PiretanideFormestane may increase the hypokalemic activities of Piretanide.Experimental
PirfenidoneThe risk or severity of adverse effects can be increased when Pirfenidone is combined with Formestane.Investigational
PiroxicamThe risk or severity of adverse effects can be increased when Piroxicam is combined with Formestane.Approved, Investigational
Polyestradiol phosphateThe serum concentration of Formestane can be increased when it is combined with Polyestradiol phosphate.Approved
PolythiazideFormestane may increase the hypokalemic activities of Polythiazide.Approved
PosaconazoleThe serum concentration of Formestane can be increased when it is combined with Posaconazole.Approved, Investigational, Vet Approved
PrimidoneThe serum concentration of Formestane can be decreased when it is combined with Primidone.Approved, Vet Approved
PromestrieneThe serum concentration of Formestane can be increased when it is combined with Promestriene.Investigational
PropacetamolThe risk or severity of adverse effects can be increased when Propacetamol is combined with Formestane.Approved
PrulifloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Prulifloxacin.Investigational
PTC299The risk or severity of adverse effects can be increased when PTC299 is combined with Formestane.Investigational
PyridostigmineThe risk or severity of adverse effects can be increased when Formestane is combined with Pyridostigmine.Approved
QuinestrolThe serum concentration of Formestane can be increased when it is combined with Quinestrol.Approved
QuinethazoneFormestane may increase the hypokalemic activities of Quinethazone.Approved
Rabies virus inactivated antigen, AThe risk or severity of adverse effects can be increased when Formestane is combined with Rabies vaccine.Approved
RapacuroniumRapacuronium may increase the adverse neuromuscular activities of Formestane.Withdrawn
ResveratrolThe risk or severity of adverse effects can be increased when Resveratrol is combined with Formestane.Experimental, Investigational
RifabutinThe serum concentration of Formestane can be decreased when it is combined with Rifabutin.Approved
RifampicinThe serum concentration of Formestane can be decreased when it is combined with Rifampicin.Approved
RifapentineThe serum concentration of Formestane can be decreased when it is combined with Rifapentine.Approved
RindopepimutThe risk or severity of adverse effects can be increased when Formestane is combined with CDX-110.Investigational
RitonavirThe serum concentration of Formestane can be increased when it is combined with Ritonavir.Approved, Investigational
RivastigmineThe risk or severity of adverse effects can be increased when Formestane is combined with Rivastigmine.Approved, Investigational
RofecoxibThe risk or severity of adverse effects can be increased when Rofecoxib is combined with Formestane.Investigational, Withdrawn
RosoxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Rosoxacin.Approved
SalicylamideThe risk or severity of adverse effects can be increased when Salicylamide is combined with Formestane.Approved
Salicylic acidThe risk or severity of adverse effects can be increased when Salicylic acid is combined with Formestane.Approved, Vet Approved
SalsalateThe risk or severity of adverse effects can be increased when Salsalate is combined with Formestane.Approved
SaquinavirThe serum concentration of Formestane can be increased when it is combined with Saquinavir.Approved, Investigational
SecoisolariciresinolThe serum concentration of Formestane can be increased when it is combined with Secoisolariciresinol.Investigational
SeratrodastThe risk or severity of adverse effects can be increased when Seratrodast is combined with Formestane.Approved
SparfloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Sparfloxacin.Approved
SRP 299The risk or severity of adverse effects can be increased when Formestane is combined with SRP 299.Investigational
SRT501The risk or severity of adverse effects can be increased when SRT501 is combined with Formestane.Investigational
St. John's WortThe serum concentration of Formestane can be decreased when it is combined with St. John&#39;s Wort.Nutraceutical
StanozololFormestane may increase the fluid retaining activities of Stanozolol.Approved, Vet Approved
SulfasalazineThe risk or severity of adverse effects can be increased when Sulfasalazine is combined with Formestane.Approved
SulindacThe risk or severity of adverse effects can be increased when Sulindac is combined with Formestane.Approved
SuprofenThe risk or severity of adverse effects can be increased when Suprofen is combined with Formestane.Approved, Withdrawn
Synthetic Conjugated Estrogens, AThe serum concentration of Formestane can be increased when it is combined with Synthetic Conjugated Estrogens, A.Approved
Synthetic Conjugated Estrogens, BThe serum concentration of Formestane can be increased when it is combined with Synthetic Conjugated Estrogens, B.Approved
TacrineThe risk or severity of adverse effects can be increased when Formestane is combined with Tacrine.Withdrawn
TelaprevirThe serum concentration of Telaprevir can be decreased when it is combined with Formestane.Withdrawn
TelithromycinThe serum concentration of Formestane can be increased when it is combined with Telithromycin.Approved
TemafloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Temafloxacin.Withdrawn
TenoxicamThe risk or severity of adverse effects can be increased when Tenoxicam is combined with Formestane.Approved
TepoxalinThe risk or severity of adverse effects can be increased when Tepoxalin is combined with Formestane.Vet Approved
TeriflunomideThe risk or severity of adverse effects can be increased when Teriflunomide is combined with Formestane.Approved
TestosteroneFormestane may increase the fluid retaining activities of Testosterone.Approved, Investigational
TG4010The risk or severity of adverse effects can be increased when Formestane is combined with TG4010.Investigational
Tiaprofenic acidThe risk or severity of adverse effects can be increased when Tiaprofenic acid is combined with Formestane.Approved
TiboloneThe serum concentration of Formestane can be increased when it is combined with Tibolone.Approved
TinoridineThe risk or severity of adverse effects can be increased when Tinoridine is combined with Formestane.Investigational
Tolfenamic AcidThe risk or severity of adverse effects can be increased when Tolfenamic Acid is combined with Formestane.Approved
TolmetinThe risk or severity of adverse effects can be increased when Tolmetin is combined with Formestane.Approved
TorasemideFormestane may increase the hypokalemic activities of Torasemide.Approved
TranilastThe risk or severity of adverse effects can be increased when Tranilast is combined with Formestane.Approved, Investigational
TrastuzumabTrastuzumab may increase the cardiotoxic activities of Formestane.Approved, Investigational
TrichlorfonThe risk or severity of adverse effects can be increased when Formestane is combined with Trichlorfon.Vet Approved
TrichlormethiazideFormestane may increase the hypokalemic activities of Trichlormethiazide.Approved, Vet Approved
TrovafloxacinThe risk or severity of adverse effects can be increased when Formestane is combined with Trovafloxacin.Approved, Withdrawn
TubocurarineThe risk or severity of adverse effects can be increased when Formestane is combined with Tubocurarine.Approved
ValdecoxibThe risk or severity of adverse effects can be increased when Valdecoxib is combined with Formestane.Investigational, Withdrawn
VoriconazoleThe serum concentration of Formestane can be increased when it is combined with Voriconazole.Approved, Investigational
WarfarinFormestane may increase the anticoagulant activities of Warfarin.Approved
ZaltoprofenThe risk or severity of adverse effects can be increased when Zaltoprofen is combined with Formestane.Approved
ZeranolThe serum concentration of Formestane can be increased when it is combined with Zeranol.Vet Approved
ZileutonThe risk or severity of adverse effects can be increased when Zileuton is combined with Formestane.Approved, Investigational, Withdrawn
ZomepiracThe risk or severity of adverse effects can be increased when Zomepirac is combined with Formestane.Withdrawn
Food Interactions
Not Available

References

Synthesis Reference

Kohler, Maxie, et al. "Metabolism of 4-hydroxyandrostenedione and 4-hydroxytestosterone: Mass spectrometric identification of urinary metabolites." Steroids 72.3 (2007): 278-286.

General References
  1. Perez Carrion R, Alberola Candel V, Calabresi F, Michel RT, Santos R, Delozier T, Goss P, Mauriac L, Feuilhade F, Freue M, et al.: Comparison of the selective aromatase inhibitor formestane with tamoxifen as first-line hormonal therapy in postmenopausal women with advanced breast cancer. Ann Oncol. 1994;5 Suppl 7:S19-24. [PubMed:7873457 ]
  2. Kohler M, Parr MK, Opfermann G, Thevis M, Schlorer N, Marner FJ, Schanzer W: Metabolism of 4-hydroxyandrostenedione and 4-hydroxytestosterone: Mass spectrometric identification of urinary metabolites. Steroids. 2007 Mar;72(3):278-86. Epub 2007 Jan 17. [PubMed:17207827 ]
  3. Lonning PE, Geisler J, Johannessen DC, Gschwind HP, Waldmeier F, Schneider W, Galli B, Winkler T, Blum W, Kriemler HP, Miller WR, Faigle JW: Pharmacokinetics and metabolism of formestane in breast cancer patients. J Steroid Biochem Mol Biol. 2001 Apr;77(1):39-47. [PubMed:11358673 ]
  4. Murray R, Pitt P: Treatment of advanced breast cancer with formestane. Ann Oncol. 1994;5 Suppl 7:S11-3. [PubMed:7873455 ]
  5. Vorobiof DA, Kleeberg UR, Perez-Carrion R, Dodwell DJ, Robertson JF, Calvo L, Dowsett M, Clack G: A randomized, open, parallel-group trial to compare the endocrine effects of oral anastrozole (Arimidex) with intramuscular formestane in postmenopausal women with advanced breast cancer. Ann Oncol. 1999 Oct;10(10):1219-25. [PubMed:10586340 ]
External Links
KEGG Drug
D07260
PubChem Compound
11273
PubChem Substance
175427144
ChemSpider
10799
BindingDB
225704
ChEBI
75172
ChEMBL
CHEMBL132530
Drugs.com
Drugs.com Drug Page
Wikipedia
Formestane
ATC Codes
L02BG02 — Formestane
AHFS Codes
Not Available
PDB Entries
Not Available
FDA label
Not Available
MSDS
Download (279 KB)

Clinical Trials

Clinical Trials
Not Available

Pharmacoeconomics

Manufacturers
Not Available
Packagers
Not Available
Dosage forms
FormRouteStrength
Liquid; powder, for solutionIntramuscular
Prices
Not Available
Patents
Not Available

Properties

State
Solid
Experimental Properties
PropertyValueSource
melting point (°C)199 - 202 MSDS
water solubilityInsoluble MSDS
logP2.66MSDS
pKa9.31MSDS
Predicted Properties
PropertyValueSource
Water Solubility0.0578 mg/mLALOGPS
logP2.57ALOGPS
logP3.41ChemAxon
logS-3.7ALOGPS
pKa (Strongest Acidic)9.21ChemAxon
pKa (Strongest Basic)-3.7ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area54.37 Å2ChemAxon
Rotatable Bond Count0ChemAxon
Refractivity85.57 m3·mol-1ChemAxon
Polarizability34.07 Å3ChemAxon
Number of Rings4ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted ADMET features
PropertyValueProbability
Human Intestinal Absorption+1.0
Blood Brain Barrier+0.9628
Caco-2 permeable+0.8149
P-glycoprotein substrateSubstrate0.6597
P-glycoprotein inhibitor IInhibitor0.7113
P-glycoprotein inhibitor IINon-inhibitor0.8526
Renal organic cation transporterNon-inhibitor0.7227
CYP450 2C9 substrateNon-substrate0.8331
CYP450 2D6 substrateNon-substrate0.9308
CYP450 3A4 substrateSubstrate0.753
CYP450 1A2 substrateNon-inhibitor0.9046
CYP450 2C9 inhibitorNon-inhibitor0.9443
CYP450 2D6 inhibitorNon-inhibitor0.941
CYP450 2C19 inhibitorNon-inhibitor0.9025
CYP450 3A4 inhibitorNon-inhibitor0.85
CYP450 inhibitory promiscuityLow CYP Inhibitory Promiscuity0.9027
Ames testNon AMES toxic0.9311
CarcinogenicityNon-carcinogens0.9537
BiodegradationNot ready biodegradable0.963
Rat acute toxicity1.6135 LD50, mol/kg Not applicable
hERG inhibition (predictor I)Weak inhibitor0.9479
hERG inhibition (predictor II)Non-inhibitor0.7566
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397 )

Spectra

Mass Spec (NIST)
Not Available
Spectra
SpectrumSpectrum TypeSplash Key
LC-MS/MS Spectrum - , positiveLC-MS/MSsplash10-01t9-2920000000-24696d73561fe3ce6680
Predicted LC-MS/MS Spectrum - 10V, PositivePredicted LC-MS/MSNot Available
Predicted LC-MS/MS Spectrum - 20V, PositivePredicted LC-MS/MSNot Available
Predicted LC-MS/MS Spectrum - 40V, PositivePredicted LC-MS/MSNot Available
Predicted LC-MS/MS Spectrum - 10V, NegativePredicted LC-MS/MSNot Available
Predicted LC-MS/MS Spectrum - 20V, NegativePredicted LC-MS/MSNot Available
Predicted LC-MS/MS Spectrum - 40V, NegativePredicted LC-MS/MSNot Available

Taxonomy

Description
This compound belongs to the class of chemical entities known as androgens and derivatives. These are 3-hydroxylated C19 steroid hormones. They are known to favor the development of masculine characteristics. They also show profound effects on scalp and body hair in humans.
Kingdom
Chemical entities
Super Class
Organic compounds
Class
Lipids and lipid-like molecules
Sub Class
Steroids and steroid derivatives
Direct Parent
Androgens and derivatives
Alternative Parents
Hydroxysteroids / 3-oxo delta-4-steroids / 17-oxosteroids / Delta-4-steroids / Cyclohexenones / Enols / Organic oxides / Hydrocarbon derivatives
Substituents
Androgen-skeleton / 3-oxo-delta-4-steroid / 3-oxosteroid / Oxosteroid / 17-oxosteroid / 4-hydroxysteroid / Hydroxysteroid / Delta-4-steroid / Cyclohexenone / Cyclic ketone
Molecular Framework
Aliphatic homopolycyclic compounds
External Descriptors
enol, 3-oxo Delta(4)-steroid, 17-oxo steroid, hydroxy steroid (CHEBI:75172 )
Drug created on June 13, 2013 22:20 / Updated on September 01, 2017 12:00