Use of estetrol as emergency contraceptive

Abstract

The present invention relates to a new use of tetrahydroxylated estrogens such as estetrol (1,3,5(10)-estratrien-3, 15α, 16α, 17β-tetrol), namely in a method of emergency contraception. The method of emergency contraception according to the invention comprises the oral administration of estetrol in a single dose within 120 hours of sexual intercourse.

1 . A method of emergency contraception in a mammalian female comprising the administration of an emergency contraceptive comprising tetrahydroxylated estrogen represented by the general formula (I): 
       
         
           
           
               
               
           
         
         wherein R1, R2, R3, R4 independently are a hydrogen atom; a hydroxyl group, an alkoxy group with 1-5 carbon atoms, or a keto group; 
         wherein each of R5, R6, R7 is a hydroxyl group; and 
         wherein no more than 3 of R1, R2, R3, R4 are hydrogen atoms, 
         in an effective amount to inhibit ovulation and pregnancy in a female mammal. 
       
     
     
         2 . The method according to  claim 1 , wherein said administration is performed through non-vaginal administration 
     
     
         3 . The method according to any one of  claim 1  or  2 , wherein said administration is performed through oral, parenteral, rectal, transcutaneous or topical administration. 
     
     
         4 . The method according to any one of  claims 1  to  3 , wherein said emergency contraceptive additionally comprises a pharmaceutically acceptable salt of said tetrahydroxylated estrogen or excipient. 
     
     
         5 . The method according to any one of  claims 1  to  4 , wherein said emergency contraceptive additionally comprises one or more additional ingredients. 
     
     
         6 . The method according to any one of  claims 1  to  5 , wherein said tetra-hydroxylated estrogen is estetrol (1,3,5(10)-estratrien-3, 15α, 16α, 17β-tetrol). 
     
     
         7 . The method according to any one of  claims 1  to  6 , wherein said emergency contraceptive comprises the tetra-hydroxylated estrogen in a dose of between 0.5 and 7 mg/kg, between 1.0 to 5.0 mg/kg, between 1.5 to 2.5 mg/kg, or of about 2.0 mg/kg 
     
     
         8 . The method according to any one of  claims 1  to  6 , wherein said emergency contraceptive comprises the tetra-hydroxylated estrogen in a dose of between 30 mg and 400 mg, between 40 mg and 250 mg, between 40 mg and 200 mg, between 40 mg and 150 mg, between 40 mg and 100 mg, between 50 mg and 100 mg of estetrol, or of about 100 mg. 
     
     
         9 . The method according to any one of  claims 1  to  8 , wherein the administration is performed in a single dosage. 
     
     
         10 . The method according to  claim 1  to  8 , wherein the administration is performed in a double dosage, e.g. with an interval of 6, 12, 18, or 24 hours. 
     
     
         11 . The method according to any one of  claims 1  to  10 , wherein said administration is performed within 120 hours after sexual intercourse, preferably within 96, 72, 48, 24, 12 hours or less.