USE OF PARATHORMONE, OF ITS BIOLOGICALLY ACTIVE FRAGMENTS AND OF RELATED PEPTIDES FOR TREATMENT OF PREGNANCY

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: USE OF PARATHORMONE, OF ITS BIOLOGICALLY ACTIVE FRAGMENTS AND OF RELATED PEP¬ TIDES FOR TREATMENT OF PREGNANCY Field of invention 5 The present invention refers to the use of Parathormone, its biologically active fragments and correlated peptides (PTHrP) for the preparation of pharmaceutical compositions useful in the prevention and therapy of abortion and of premature birth and in general for the treatment of pregnancy. 10 Status of technique By the generic term Parathormone or parathyroid hormones (commonly indicated by the initials PTH eventually followed by the number of amino acids characterising the particular fragment) it is intended a series of proteins or their 15 fragments which can be found in nature and are assigned to different physiological effects. Such effects concern principally the regulation of calcemic homeostasis, favouring the intestinal calcium absorption by the indirect mechanism of hydroxylation of Vitamin D, increasing 20 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 the 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 used in the unit USP defined as one hundredth of the amount of parathyroid hormone required to increase by 1 mg the calcium contained in 100 ml of normal dog serum within 16-18 hours from administration. Some studies reported in the literature indicate an in vitro action of parathormone, of its fragments and of 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, of its fragments or of PTHrP on the contractility of human myometrium and, 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. Since the rat uterus is formed by fiber cells completely different from those of the human myometrium it was not possible, according to such studies, to foresee the possibility to use such products in the prevention of abortion and premature birth seen that 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. Sperelakis N. et al. in "Fast Na+ channels in smooth muscle from pregnant rat uterus" - Can. J. Physiol. Pharmacol. (70) 491-500 (1992) have demonstrated the existence of such channels in rat uterus. The concentration of receptors for oxytocin on myometrium membranes resulted quantitatively similar in human and guinea pig uterus but approximately twice of that found in rat [Fuchs A.R. et al. in "Oxytocin antagonist and oxytocin receptors in myometrium and decidua" - Am. J. Perinatol . (6), 205-208 (1989)]. Lopez Bernal A. et al. in "Are leukotrienes involved in human uterine contractility?" - Br. J. Obstet. Gynaecol. (96) 568-573 (1989) have confirmed that oxytocin does not contract the nonpregnant human uterus but contracts the non-pregnant rat uterus. 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. 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, as demonstrated by Black J.W. et al. in "Definition and Antagonism of histamine H2-receptors" - Nature (236) , 385" 390 (1972) while the human uterus always reacts with a contraction due to the activation of HI receptors [Cruz M. et al. in "Effects of histamine and serotonin on the contractility of isolated pregnant and nonpregnant human myometrium" - Gynecol. Obstet. Invest. (28), 1-4 (1989)]. Furthermore, G. Ballejo et al. in "In vitro effects of calcium entry blockers , chlorpromazine and fenoterol upon human pregnant myometrium contractility" - Br. J. Pharmacol. (89), 515-523 (1986) have demonstrated that the response of the myometrium can depend on the animal species since the sensibility to calcium in human uterus and in nonpregnant dog uterus did not result to be different [Calixto J.B. e Antonio A.: effects of Compound D600 (methoxyverapamil) on drug- -induced-contractions of isolated dog uterine muscle" - Gen. Pharmacol. (17). 203-209 (1986)] while in the nonpregnant rat myometrium the potency of CaCl2 in inducing contractions in a solution rich of K + and Ca + was about 30-40 times higher than that shown in their studies on human myometrium [Calixto J.B. and Loch S.: "Ketamine inhibition of calcium-induced contractions in depolarized uterus. A comparison with other calcium antagonists" - 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 decription of the graphs Graph 1 shows the protracted stimulation of contractions induced on human myometrium by oxytocin (Ox) at a dose of 1 x 10 "2 U Graph 2 shows the inhibitory effect (flat trace) induced by -A intact human parathormone at a dose of 8.5 x 10 M on human _2 myometrium stimulated with oxytocin at a dose of 1 x 10 U. Graph 3 shows typical contractions induced by PGF2alpha (1 Ng/kg) indicating intensity and duration. Graph 4 shows the response at the same dosage as in Graph 3 after administration of intact human PTH at a dose of 4 x 10 mg/kg. Graph 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 graphs 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 allows the use of Parathormone, its active fragments or correlated peptides for the preparation of pharmaceutical compositions 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 considered for intravenous, intramuscular, subcutaneous, rectal and vaginal administration. The types of formulations can be briefly summarized as follows: an in ectable pharmaceutical form in whichthe active ingredient is in the liquid phase or, better yet lyophilized, with 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 form 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 propylenglycols 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 form 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 comprised 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) , by rectal administration (Examples 7 _ l4) and by 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 g Phosphate-citrate buffer pH 2.5 ~ 3 7-5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 2 PTH (or fragment thereof) 100000 U (USP) Lactose 10.0 g Human albumin 20.0 g Phosphate-citrate buffer pH 2.5 - 3 7-5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 3 PTH (or fragment thereof) 500000 U (USP) Mannitol 15-0 g PVP 15.0 g Phosphate-citrate buffer pH 2.5 - 3 7-5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 4 PTH (or fragment thereof) 750000 U (USP) Glycine 25.0 g Peptone 25-0 g Phosphate-citrate buffer pH 2.5 - 3 7-5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 5 PTH (or fragment thereof) 400000 U (USP) Human albumin 25-0 g Phosphate-citrate buffer pH 2.5 ~ 3 7-5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 6 PTH (or fragment thereof) 400000 U (USP) Lactose 10.0 g Human albumin 25-0 g Phosphate-citrate buffer pH 2.5 - 3 7.5 g Water for injections (USP) q.s. to 1000 ml EXAMPLE 7 PTH (or fragment thereof) 500000 U (USP) Human albumin 20.0 g Phosphate-citrate buffer pH 2.5 - 3 7-5 g Glycerin 50.0 g Polyethylene glycol 600 900.0 g Polyethylene glycol 4000 75-0 g Purified Water 2.0 g EXAMPLE 8 PTH (or fragment thereof) Human albumin Phosphate-citrate buffer pH 2.5 - 3 Glycerin Polyethylene glycol 600 Polyethylene glycol 4000 Purified Water EXAMPLE 9 PTHrP (or fragment thereof) Human albumin Phosphate-citrate buffer pH 2.5 - 3 Glycerin Polyethylene glycol 600 Polyethylene glycol 4000 Purified Water 2.0 g EXAMPLE 10 PTH (or fragment thereof) 500000 U (USP) Human albumin 20.0 g Phosphate-citrate buffer pH 2.5 - 3 7-5 g Glycerin 40.0 g Polyethylene glycol 400 250.0 g Polyethylene glycol 200 500.0 g Polyethylene glycol 4000 100.0 g Sorbitol 10.0 g Purified Water 5. ' 0 g EXAMPLE 11 PTH (or fragment thereof) 500000 U (USP) Human albumin 15-0 g Glycerin 50.0 g Phosphate-citrate buffer pH 2.5 - 3 15-0 g Polyethylene glycol 600 900.0 g Polyethylene glycol 4000 75-0 g EXAMPLE 12 PTHrP 500000 U (USP) Human albumin 15-0 g Glycerin 50.0 g Phosphate-citrate buffer pH 2.5 15-0 g Purified Water 2.0 g EXAMPLE 16 PTHrP Human albumin Glycerin Phosphate-citrate buffer pH 2.5 - 3 Polyethylene glycol 600 Polyethylene glycol 4000 Purified Water EXAMPLE 17 PTH (or fragment thereof) Peptone Glycerin Phosphate-citrate buffer pH 2.5 - 3 Polyethylene glycol 600 Polyethylene glycol 4000 Purified Water EXAMPLE 18 PTH (or fragment thereof) PVP Glycerin Phosphate-citrate buffer pH 2.5 - 3 Polyethylene glycol 600 Polyethylene glycol 4000 Purified Water 2.0 g Experimental Trials on the in vitro motility of fragments of myometrium of pregnant women By using "in vitro" fragments of myometrium taken during caesarean birth according to the technique described in "IL FARMACO", Edizione Scientifica 31: pages 329"336 (1976) a net inhibitory effect on contraction induced by oxytocyn has been observed, as can be seen in graphs 1 and 2 attached. In graph 2 there is a net inhibitory effect, indicated in the flat trace, induced by intact human Parathormone (PTH) at a _Q dose of 8.5 x 10 M, on human myometrium stimulated with _2 oxytocyn at a dose of 1x10 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 1x10 U (graph 1). Furthermore, Parathormone has neen also essayed for the contractions induced by PGF2alpha according to the technique described in the British Journal of Pharmacology 93: 185-191 (1988). Graph 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 graph 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 x 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 threatened premature bith have been observed while in their 34~36th week of pregnancy. The patients underwent a cardiotocography which showed waves revealing uterine contractions. Arterial pressure, hearth 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 (Graph 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.

Claims: CLAIMS 1. Use of Parathormone, its active fragments and correlated peptides, for the preparation of pharmaceutical compositions useful in the prevention of abortion, premature birth and treatment of pregnancy. 2. Use according to claim 1 in which the products indicated are chosen from the group made of: PTH, PTH 1-34, PTH 1-13, PTH 38- 64, PTH 67-86, PTHrP. 3- Use according to claim 2 in which the product used is Parathormone. 4. Use according to claim 3 in which the composition includes appropriate carriers for intravenous, intramuscular, subcuntaneous, rectal and vaginal administration. 5- Use according to claim 4 in which the active ingredient is present in quantities of 100 and 1000 U (USP) . 6. Use according to claim in which the active principle is present in quantities of 400 to 800 U (USP) .

Inventors: BAGNOLI FRANCO, BAGNOLI, FRANCO
Applicants: BAGNOLI FRANCO, BAGNOLI, FRANCO
Application year: 1993
Main classification: A61K37
IPC codes: A61K38, A61P13, A61P15