MS-2 Step

What it is

MS-2 Step consists of Mifepristone Linepharma 200 mg tablet and GyMiso® misoprostol 200 microgram tablets in combination. Mifepristone is a synthetic steroid with an antiprogestational action as a result of competition with progesterone at the progesterone receptors. Misoprostol is a synthetic analogue of prostaglandin E1.

Approved indications

— Medical termination of an intrauterine pregnancy, up to 63 days of gestation, in females of childbearing age.

Dosing overview

Mifepristone is administered at 200 mg orally, followed 36 to 48 hours later by misoprostol. Misoprostol is administered at 800 micrograms buccally (4 tablets, each containing 200 micrograms), kept between the cheek and the gum for 30 minutes before any fragments being swallowed with water. MS-2 Step should be taken 2 hours before or 2 hours after a meal.

Key safety warnings

Rare serious cardiovascular accidents including cardiac arrest, myocardial infarction and/or spasm of the coronary arteries and severe hypotension have been reported following administration of prostaglandins including misoprostol, and women with risk factors for cardiovascular disease or established cardiovascular disease should be treated with caution. Due to the antiglucocorticoid activity of mifepristone, the efficacy of long-term corticosteroid therapy, including inhaled corticosteroids in asthmatic patients, may be decreased during the 3 to 4 days following intake of mifepristone, and therapy should be adjusted. Severe cutaneous adverse reactions, including toxic epidermal necrolysis and acute generalised exanthematous pustulosis, have been reported in association with mifepristone, and in patients who experience these reactions, treatment should be immediately discontinued and re-treatment with mifepristone is not recommended. Angioedema of the face, lips, tongue, and/or larynx, including cases of anaphylaxis have been reported in post-market surveillance, and angioedema associated with upper airway swelling may be life threatening, requiring appropriate therapy and measures necessary to ensure a patent airway to be promptly provided. The patient must be informed of prolonged vaginal bleeding (an average of 10 to 16 days after intake), which may be heavy, occurs in almost all cases and is not proof of complete expulsion, with persistent bleeding being a consequence of incomplete expulsion that can be large enough to necessitate a blood transfusion in up to 0.2% of cases up to 63 days gestation. Cases of serious bacterial infection, including very rare cases of fatal septic shock, have been reported following the use of mifepristone and misoprostol, and treating healthcare practitioners should be alert to this rare event, particularly where sustained fever of 38ºC or higher, severe abdominal pain, or pelvic tenderness occurs in the days after a medical abortion.

Contraindications

MS-2 Step should not be prescribed in patients lacking access to emergency medical care in the 14 days following start of treatment. It is contraindicated in suspected or confirmed ectopic pregnancy, uncontrolled asthma, intrauterine device in place, uncertainty about gestational age, chronic adrenal failure, concurrent long term corticosteroid therapy, suspected or known haemorrhagic disorders or treatment with anticoagulants, hypersensitivity to mifepristone, misoprostol or any prostaglandin or excipients, and pregnancy not confirmed by ultrasound or biological test such as urine or serum hCG.

PBS listing

No sources provide information about PBS listing, including strength, item count, restriction type, or ex-manufacturer price.

Regulatory history

MS-2 Step was first listed on the ARTG on 4 June 2014. An AusPAR approval was granted on 28 June 2023 for changes to the Product Information and Risk Management Plan, amending prescriber eligibility to 'healthcare practitioners' and removing requirements for pharmacist registration, mandatory prescriber training/certification, and the 24-hour telephone nurse aftercare service.