Abstract:
Pharmaceutical compositions containing Parathormone as active ingredient, its biologically active fragments and correlated peptides (PTHrP), eventually in combination with appropriate pharmaceutically acceptable additives, useful in the prevention and therapy of abortion and of premature birth and in general for the treatment of pregnancy are described.

Description:
FIELD OF INVENTION 
     The present invention relates to the use of Parathormone, its biologically active fragments and its correlated peptides (PTHrP) for the prevention and therapy of abortion and of premature birth and in general for the treatment of pregnancy. 
     BACKGROUND OF THE INVENTION 
     The generic term Parathormone or parathyroid hormones (commonly indicated by the initials PTH eventually followed by the number of amino acids characterizing the particular fragment) refers to a series of proteins or their fragments which can be found in nature and are assigned to different physiological effects. 
     Such effects relate principally to the regulation of calcemic homeostasis, favouring the intestinal calcium absorption by the indirect mechanism of hydroxylation of Vitamin D, increasing the re-absorption of calcium in the renal tubules and activating the osteoclasts. More recently it was shown that PTH and PTHrP have a relaxing action on the gastrointestinal muscles and on vascular tissue. Moreover, an increase of hematic flow in the coronaries and a positive chronotropic effect and negative inotropic effect have been demonstrated. 
     The hormone and its fragments are dosed biologically and the measurement system presently most often used is the USP unit defined as one hundredth of the amount of parathyroid hormone required to increase the calcium contained in 100 ml of normal dog serum by 1 mg within 16-18 hours from administration. 
     Some studies reported in the literature indicate an in vitro action of parathormone, its fragments and the correlated peptide (PTHrP) on the contractility of rat uterus. According to such studies PTH has an inhibitory action on the contractility of the uterus induced by oxytocin, acetylcholine and prostaglandin. 
     Literature does not report studies evaluating the action of PTH, its fragments or PTHrP on the contractility of human myometrium, Furthermore, the data reported above cannot suggest results obtainable on the human uterus because the structural and physiological differences between these two tissues do not allow any predictability. 
     The rat uterus is formed of fiber cells which are completely different from those of the human myometrium. It was, therefore, not possible, according to such studies, to foresee the possibility of using such products in the prevention of abortion and premature birth in humans, since the data obtained in animals cannot be extrapolated to humans. In fact, the smooth muscles (including the human myometrium) do not normally possess fast Na+ channels, while the existence of such channels has been demonstrated in the rat uterus. Sperelakis N. et al., &#34;Fast Na+ channels in smooth muscle from pregnant rat uterus,&#34; Can. J. Physiol. Pharmacol. (70) 491-500 (1992). Furthermore, although the concentration of receptors for oxytocin on myometrium membranes is quantitatively similar in human and guinea pig uterus, it was approximately twice that found in rat. Fuchs A. R. et al., &#34;Oxytocin antagonist and oxytocin receptors in myometrium and decidua,&#34; Am. J. Perinatol. (6), 205-208 (1989). Moreover, Lopez Bernal A. et al. have confirmed that oxytocin does not contract the nonpregnant human uterus but contracts the non-pregnant rat uterus. Lopez Bernal A. et al., &#34;Are leukotrienes involved in human uterine contractility?&#34; Br. J. Obstet. Gynaecol. (96) 568-573 (1989). 
     We must also consider the remarkable structural differences of the two organs involved. In fact, the response of a sample of rat uterus is mostly due to the activity of longitudinal muscles while the response of human myometrium strips results from different muscular components. In addition, the behaviour of the two myometriums with respect to histamine is well known. The rat uterus in estrus responds to histamine with an inhibition which is connected to the activation of H2 receptors. Black J. W. et al., &#34;Definition and Antagonism of histamine H2-receptors,&#34; Nature (236), 385-390 (1972). The human uterus always reacts with a contraction due to the activation of H1 receptors. Cruz M. et al., &#34;Effects of histamine and serotonin on the contractility of isolated pregnant and nonpregnant human myometrium,&#34; Gynecol. Obstet. Invest. (28), 1-4 (1989). 
     Furthermore, G. Ballejo et al. have demonstrated that the response of the myometrium can depend on the animal species since the sensitivity to calcium in human uterus and in nonpregnant dog uterus did not result to be different, while in the nonpregnant rat myometrium the potency of CaCl 2  in inducing contractions in a solution rich of K +   and Ca 2+   was about 30-40 times higher than that shown in their studies on human myometrium. G. Ballejo et al., &#34;In vitro effects of calcium entry blockers, chlorpromazine and fenoterol upon human pregnant myometrium contractility,&#34; Br. J. Pharmacol. (89), 515-523 (1986); Calixto J. B. e Antonio A., &#34;Effects of Compound D600 (methoxyverapamil) on drug-induced-contractions of isolated dog uterine muscle,&#34; Gen. Pharmacol. (17), 203-209 (1986);Calixto J. B. and Loch S., &#34;Ketamine inhibition of calcium-induced contractions in depolarized uterus. A comparison with other calcium antagonists,&#34; Br. J. Pharmacol. (85). 189-195 (1985). In conclusion, therefore, the effects observed on the human uterus cannot be extrapolated from those obtained on the rat uterus but, rather, the effect noted in vitro on human uterus is surprising. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows the protracted stimulation of contractions induced on human myometrium, by oxytocin (Ox) at a dose of 1×10 -2  U 
     FIG. 2 shows the inhibitory effect (flat trace) induced by intact human parathormone at a dose of 8.5×10 -8  M on human myometrium stimulated with oxytocin at a dose of 1×10 -2  U. 
     FIG. 3 shows typical contractions induced by PGF 2  alpha (1 mg/kg) indicating intensity and duration. 
     FIG. 4 shows the response at the same dosage as in FIG. 3 after administration of intact human PTH at a dose of 4×10 -4  mg/kg. 
     FIG. 5 reports on the left side the basal value of uterine contractility and fetal heart rate in a pregnant woman; the same parameters after 10 infusion with PTH 200 U are reported on the right side. 
     In the figures the dots (·) indicate the moment of administration of the indicated substance; W (Washing) indicates the washing of the preparation. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates to the use of Parathormone, its active fragments or correlated peptides for the prevention of abortion and premature birth and in general for the treatment of pregnancy. For the purposes of the present invention the following are particularly indicated: PTH, PTH 1-34. PTH 1-13, PTH 38-64, PTH 67-86, PTHrP. 
     The compositions can be formulated for intravenous, intramuscular, subcutaneous, rectal and vaginal administration. The types of formulations can be briefly summarized as follows: an injectable pharmaceutical form in which the active ingredient is in the liquid phase or, preferably lyophilized, in the presence eventually of an appropriate stabilizing agent (albumin, peptone, PVP, etc.), an appropriate support (in case of lyophilized product: lactose, mannitol, glycine, etc.) and of a buffer mixture capable of assuring the most appropriate pH for its stability; a rectal pharmaceutical formulation represented by a suppository or preferably a soft gelatine capsule containing the active ingredient suspended in a mixture of water soluble excipients including essentially polyethylene glycols and/or propyleneglycols having the necessary fluidity, with the addition of a polyalcohol such as glycerin and eventually a stabilizing agent (albumin, peptone, PVP, etc. ) and a buffer mixture necessary to maintain the pH in a range of values compatible with PTH and/or its active fragments; a vaginal pharmaceutical formulation such as a vaginal suppository or preferably soft gelatine vaginal ovule containing the active ingredient suspended in a mixture of water soluble excipients essentially similar to that contained in the soft gelatine capsule for rectal use. 
     The quantity of active ingredient can vary between 100 to 1000 Units, but is preferably between 400 and 800 Units. The following examples describe pharmaceutical formulations containing PTH or its biologically active fragments, which can be used by injection (Examples 1-6), rectal administration (Examples 7-14) and vaginal administration (Examples 15-18). The doses indicated refer to a formulation which can be used for the preparation of 1000 vials, rectal capsules or vaginal capsules. 
     EXAMPLE 1 
     
         ______________________________________PTH (or fragment thereof)                  100000 U (USP)Lactose                10.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 2 
     
         ______________________________________PTH (or fragment thereof)                  100000 U (USP)Lactose                10.0 gHuman albumin          20.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 3 
     
         ______________________________________PTH (or fragment thereof)                  500000 U (USP)Mannitol               15.0 gPVP                    15.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 4 
     
         ______________________________________PTH (or fragment thereof)                  750000 U (USP)Glycine                25.0 gPeptone                25.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 5 
     
         ______________________________________PTH (or fragment thereof)                  400000 U (USP)Human albumin          25.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 6 
     
         ______________________________________PTH (or fragment thereof)                  400000 U (USP)Lactose                10.0 gHuman albumin          25.0 gPhosphate-citrate buffer pH 2.5-3                  7.5 gWater for injections (USP) q.s. to 1000 ml______________________________________ 
    
     EXAMPLE 7 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)Human albumin         20.0 gPhosphate-citrate buffer pH 2.5-3                 7.5 gGlycerin              50.0 gPolyethylene glycol 600                 900.0 gPolyethylene glycol 4000                 75.0 gPurified Water        2.0 g______________________________________ 
    
     EXAMPLE 8 
     
         ______________________________________PTH (or fragment thereof)                 750000 U (USP)Human albumin         10.0 gPhosphate-citrate buffer pH 2.5-3                 7.5 gGlycerin              50.0 gPolyethylene glycol 600                 900.0 gPolyethylene glycol 4000                 75.0 gPurified Water        2.0 g______________________________________ 
    
     EXAMPLE 9 
     
         ______________________________________PTHrP (or fragment thereof)                 500000 U (USP)Human albumin         15.0 gPhosphate-citrate buffer pH 2.5-3                 7.5 gGlycerin              50.0 gPolyethylene glycol 600                 900.0 gPolyethylene glycol 4000                 75.0 gPurified Water        2.0 g______________________________________ 
    
     EXAMPLE 10 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)Human albumin         20.0 gPhosphate-citrate buffer pH 2.5-3                 7.5 gGlycerin              40.0 gPolyethylene glycol 400                 250.0 gPolyethylene glycol 200                 500.0 gPolyethylene glycol 4000                 100.0 gSorbitol              10.0 gPurified Water        5.0 g______________________________________ 
    
     EXAMPLE 11 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)Human albumin         15.0 gGlycerin              50.0 gPhosphate-citrate buffer pH 2.5-3                 15.0 gPolyethylene glycol 600                 900.0 gPolyethylene glycol 4000                 75.0 g______________________________________ 
    
     EXAMPLE 12 
     
         ______________________________________PTHrP                 500000 U (USP)Human albumin         15.0 gGlycerin              50.0 gPhosphate-citrate buffer pH 2.5-3                 15.0 gPolyethylene glycol 600                 900.0 gPolyethylene glycol 4000                 75.0 g______________________________________ 
    
     EXAMPLE 13 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)______________________________________Peptone               15.0    gGlycerin              50.0    gPhosphate-citrate buffer pH 2.5-3                 15.0    gPolyethylene glycol 600                 900.0   gPolyethylene glycol 4000                 75.0    gPurified Water        2.0     g______________________________________ 
    
     EXAMPLE 14 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)______________________________________PVP                   15.0    gGlycerin              50.0    gPhosphate-citrate buffer pH 2.5-3                 15.0    gPolyethylene glycol 600                 900.0   gPolyethylene glycol 4000                 75.0    gPurifled Water        2.0     g______________________________________ 
    
     EXAMPLE 15 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)______________________________________Human albumin         20.0    gGlycerin              80.0    gPhosphate-citrate buffer pH 2.5-3                 25.0    gPolyethylene glycol 600                 2500.0  gPolyethylene glycol 4000                 300.0   gPurified Water        2.0     g______________________________________ 
    
     EXAMPLE 16 
     
         ______________________________________PTHrP                 500000 U (USP)______________________________________Human albumin         20.0    gGlycerin              80.0    gPhosphate-citrate buffer pH 2.5-3                 15.0    gPolyethylene glycol 600                 2500.0  gPolyethylene glycol 4000                 300.0   gPurified Water        2.0     g______________________________________ 
    
     EXAMPLE 17 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)______________________________________Peptone               25.0    gGlycerin              80.0    gPhosphate-citrate buffer pH 2.5-3                 25.0    gPolyethylene glycol 600                 2500.0  gPolyethylene glycol 4000                 300.0   gPurified Water        2.0     g______________________________________ 
    
     EXAMPLE 18 
     
         ______________________________________PTH (or fragment thereof)                 500000 U (USP)______________________________________PVP                   25.0    gGlycerin              80.0    gPhosphate-citrate buffer pH 2.5-3                 25.0    gPolyethylene glycol 600                 2500.0  gPolyethylene glycol 4000                 300.0   gPurified Water        2.0     g______________________________________ 
    
     Experimental Trials on the in vitro motility of fragments of myometrium of pregnant women 
     By using &#34;in vitro&#34; fragments of myometrium taken during Caesarean birth according to the technique described in &#34;IL FARMACO&#34;, Edizione Scientifica, 31: pages 329-336 (1976), a net inhibitory effect on contraction induced by oxytocyn has been observed, as can be seen in FIGS. 1 and 2 attached. In FIG. 2 there is a net inhibitory effect, indicated in the flat trace, induced by intact human Parathormone (PTH) at a dose of 8.5×10 -8  M, on human myometrium stimulated with oxytocyn at a dose of 1×10 -2  U. The inhibitory effect induced by PTH is particularly evident when compared with the protracted stimulation of contractions induced by oxytocyn (Ox) at a dose of 1×10 -2  U (FIG. 1). 
     Furthermore. Parathormone, has also been essayed for the contractions induced by PGF2alpha according to the technique described in the British Journal of Pharmacology 93: 185-191 (1988). FIG. 3 shows a typical contraction induced by PGF2alpha (1 mg/kg) indicating intensity and duration. If we compare the same response at the same dosage on FIG. 4 we can see a clear inhibitory effect both in terms of intensity and duration as a result of administration of whole human PTH at a dose of 4×10 -4  mg/Kg. 
     In the graphs the dots (·) indicate the moment of administration of the substance indicated. The letter W (Washing) indicates the washing of the preparation. 
     Experimental clinical effects 
     Three pregnant women having symptoms indicating the likelihood of premature birth have been observed while in their 34-36th week of pregnancy. The patients underwent a cardiotocography which showed waves revealing uterine contractions. Arterial pressure, heart rate and skin coloring were evaluated. The women were clearly aware of the contractions and of the pain caused by such contractions. 
     The women were administered 100 Units of synthetic Parathormone 1-34 (two vials according to Examples 1 and 2) by rapid infusion (10 minutes), diluted in 200 cc of physiological solution. Two blood samples were taken before and after infusion and the serum was frozen and stored at -20° C. for the evaluation of the mineral elements (calcium, phosphorous, magnesium, alkaline phosphatase, parathormone, progesterone, estradiol). The results have shown the efficacy of Parathormone on uterine contractility while no side effects have been noted either in the mother or the fetus. 
     In particular, the cardiotocography has shown the disappearance of waves referring to uterine contractions during the period of monitoring (40 minutes); the fetal heart beat did not show variations and remained within the normal limits (FIG. 5). The patients indicated the immediate disappearance of uterine contractions and of pain caused by the same contractions, particularly in the lumbar-sacral region and reported also a feeling of well-being and decreased abdominal weight. The arterial pressure and heart rate did not show variations of worthwhile note and no side effects were noted in relation to the infusion of the drug. 
     
         __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 5(2) INFORMATION FOR SEQ ID NO: 1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 84 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 1:SerValSerGluIleGlnLeuMetHisAsnLeuGlyLysHisLeuAsn51015SerMetGluArgValGluTrpLeuArgLysLysLeuGlnAspValHis202530AsnPheValAlaLeuGlyAlaProLeuAlaProArgAspAlaGlySer354045GlnArgProArgLysLysGluAspAsnValLeuValGluSerHisGlu505560LysSerLeuGlyGluAlaAspLysAlaAspValAspValLeuThrLys65707580AlaLysSerGln(2) INFORMATION FOR SEQ ID NO: 2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 34 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 2:SerValSerGluIleGlnLeuMetHisAsnLeuGlyLysHisLeuAsn51015SerMetGluArgValGluTrpLeuArgLysLysLeuGlnAspValHis202530AsnPhe(2) INFORMATION FOR SEQ ID NO: 3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 13 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 3:SerValSerGluIleGlnLeuMetHisAsnLeuGlyLys510(2) INFORMATION FOR SEQ ID NO: 4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 20 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 4:TyrLeuThrGlnGluThrAsnLysValGluThrTyrLysGluGlnPro51015LeuLysThrPro20(2) INFORMATION FOR SEQ ID NO: 5:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 141 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: linear(ii) MOLECULE TYPE: protein(xi) SEQUENCE DESCRIPTION: SEQ ID NO: 5:AlaValSerGluHisGlnLeuLeuHisAspLysGlyLysSerIleGln51015AspLeuArgArgArgPhePheLeuHisHisLeuIleAlaGluIleHis202530ThrAlaGluIleArgAlaThrSerGluValSerProAsnSerLysPro354045SerProAsnThrLysAsnHisProValArgPheGlySerAspAspGlu505560GlyArgTyrLeuThrGlnGluThrAsnLysValGluThrTyrLysGlu65707580GlnProLeuLysThrProGlyLysLysLysLysGlyLysProGlyLys859095ArgLysGluGlnGluLysLysLysArgArgThrArgSerAlaTrpLeu100105110AspSerGlyValThrGlySerGlyLeuGluGlyAspHisLeuSerAsp115120125ThrSerThrThrSerLeuGluLeuAspSerArgArgHis130135140__________________________________________________________________________