Mifepristone

Mode of Action:
Mifepristone is a selective antagonist of the progesterone receptor at low doses and blocks the glucocorticoid receptor (GR-II) at higher doses. Mifepristone has high affinity for the GR-II receptor but little affinity for the GR-I (MR, mineralocorticoid) receptor. In addition, mifepristone appears to have little or no affinity for estrogen, muscarinic, histaminic, or monoamine receptors.


Brands of Mifepristone in Kenya

Mediprist®, Pharm Access Africa Limited

INDICATIONS

Medical Abortions
Mifepristone followed by a prostaglandin analog (misoprostol or gemeprost) is used for medical abortion
Cushing’s syndrome
Mifepristone is used for the medical treatment of high blood sugar caused by high cortisol levels in the blood (hypercortisolism) in adults with endogenous Cushing’s syndrome who have type 2 diabetes mellitus or glucose intolerance and have failed surgery or cannot have surgery.
Other
Mifepristone at low doses has been used for emergency contraception
Mifepristone is a cortisol receptor blocker indicated to control hyperglycemia secondary to hypercortisolism in adult patients with endogenous Cushing’s syndrome who have type 2 diabetes mellitus or glucose intolerance and have failed surgery or are not candidates for surgery.
LIMITATIONS OF USE:
Mifepristone should not be used in the treatment of patients with type 2 diabetes unless it is secondary to Cushing’s syndrome.

CONTRAINDICATIONS

Mifepristone is contraindicated in women who are pregnant. Pregnancy must be excluded before the initiation of treatment with Mifepristone or if treatment is interrupted for more than 14 days in females of reproductive potential. Non-hormonal contraceptives should be used during and one month after stopping treatment in all women of reproductive potential.
Mifepristone is contraindicated in patients taking simvastatin, lovastatin, and CYP3A substrates with narrow therapeutic ranges, such as cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus, due to an increased risk of adverse events.
Mifepristone is contraindicated in patients who require concomitant treatment with systemic corticosteroids for serious medical conditions or illnesses (e.g., immunosuppression after organ transplantation) because Mifepristone antagonizes the effect of glucocorticoids.
Mifepristone is contraindicated in the following:
Women with a history of unexplained vaginal bleeding
Women with endometrial hyperplasia with atypia or endometrial carcinoma
Mifepristone is contraindicated in patients with prior hypersensitivity reactions to mifepristone or to any of the product components.

ADVERSE DRUG REACTIONS

The following are adverse events that were reported in Study 400 at frequencies of ≥ 5% to 10%, and may be related to Mifepristone mechanism of action:
Gastrointestinal disorders: gastroesophageal reflux, abdominal pain
General disorders and administration site conditions: asthenia, malaise, edema, pitting edema, thirst
Investigations: blood triglycerides increased
Metabolism and nutrition disorders: hypoglycemia
Musculoskeletal and connective tissue disorders: muscular weakness, flank pain, musculoskeletal chest pain
Psychiatric disorders: insomnia
Reproductive system and breast disorders: vaginal hemorrhage, metrorrhagia

DRUG INTERACTIONS:

Drugs that May Reduce Mifepristone
CYP450 3A4 is primarily responsible for the metabolism of mifepristone. CYP3A4 inducers such as rifampin, dexamethasone, St. John’s Wort, and certain anticonvulsants (such as phenytoin, phenobarbital, carbamazepine) may induce mifepristone metabolism (lowering serum concentrations of mifepristone). Whether this action has an impact on the efficacy of the dose regimen is unknown.
Drugs that May Increase Mifepristone
Although specific drug or food interactions with mifepristone have not been studied, on the basis of this drug’s metabolism by CYP 3A4, it is possible that ketoconazole, itraconazole erythromycin, and grapefruit juice may inhibit its metabolism (increasing serum concentrations of mifepristone). Mifepristone should be used with caution in patients currently or recently treated with CYP 3A4 inhibitors.
Effects of Mifepristone on Other Drugs (Effect of Mifepristone on CYP 3A4Substrates)
Based on in vitro inhibition information, coadministration of mifepristone may lead to an increase in serum concentrations of drugs that are CYP 3A4 substrates. Due to the slow elimination of mifepristone from the body, such interaction may be observed for a prolonged period after its administration. Therefore, caution should be exercised when mifepristone is administered with drugs that are CYP 3A4 substrates and have a narrow therapeutic range.
Mifepristone in Kenya
Price of Mifeprisone in Kenya
Mifepristone cost in Kenya
Where to get Mifepristone in Kenya

Clinical | Pharmacokinetic data


Pregnancy Category:
Routes of Administration: By mouth
Bioavailability:
Protein Binding: 98%
Metabolosim: Liver
Onset of Action:
Elimination Half life: Following a distribution phase, elimination of mifepristone is slow at first (50% eliminated between 12 and 72 hours) and then becomes more rapid with a terminal elimination half-life of 18 hours.
Excretion: Feces: 83% Urine: 9%

Legal Status | Dosage forms & Strengths


Prescription Category:
Prescription only Medicine (POM) , ℞-only
Narcotic Drugs and Psychotropic Substances (Control ) Act Schedule:
This Drug is not Subject to DDA drugs Act
Dosage Forms | Strengths:
Tablets

Drug Indentifiers:

CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard


Drug Images

References/ Citation: