Atosiban

Drugbox
IUPAC_name = 1-(3-mercaptopropanoic acid)-
2-(O-ethyl-D-tyrosine)-4-L-threonine-
8-L-ornithine-oxytocin

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CAS_number=90779-69-4
ATC_prefix=G02
ATC_suffix=CX01
ATC_supplemental=
PubChem=68613
DrugBank=
C=43 | H=67 | N=11 | O=12 | S=2
molecular_weight = 994.199
bioavailability=
metabolism =
elimination_half-life=
excretion =
pregnancy_category =
legal_status =
routes_of_administration= intravenous

Atosiban (Tractocile or Antocin, RWJ 22164) is an inhibitor of the hormones oxytocin and vasopressin. It is used as an intravenous medication to halt premature labor. Although initial studies suggested it could be used as a nasal spray and hence would not require hospital admission, it is not used in that form. It was developed by Ferring Pharmaceuticals in Sweden and first reported in the literature in 1985. [cite journal |author=Akerlund M, Carlsson AM, Melin P, Trojnar J |title=The effect on the human uterus of two newly developed competitive inhibitors of oxytocin and vasopressin |journal=Acta Obstet Gynecol Scand. |volume=64 |issue=6 |pages=499–504 |year=1985 |pmid=4061066 |doi=]

Chemically, it is a modified form of oxytocin that inhibits the action of this hormone on the uterus, leading to a cessation of contractions. It is therefore a tocolytic.

A 2005 systematic review by the Cochrane Collaboration showed that while atosiban had less side-effects than alternative drugs (such as ritodrine), it was no better than placebo in the major outcomes, and in one study showed worse neonatal outcomes. The reviewers suggest nifedipine may be more promising. [cite journal |author=Papatsonis D, Flenady V, Cole S, Liley H |title=Oxytocin receptor antagonists for inhibiting preterm labour |journal=Cochrane database of systematic reviews (Online) |volume= |issue=3 |pages=CD004452 |year=2005 |pmid=16034931 |doi=10.1002/14651858.CD004452.pub2]

References