TREATMENT OF OCULAR DISORDERS WITH SOMATOSTATIN ANALOGUES
The present invention relates to a method of treating ocular disorders, in particular to a method of treating ocular neurodegeneration, comprising the administration of a somatostatin analogue, in particular octreotide, to an individual in need thereof.
The somatostatin class is a known class of small peptides comprising the naturally occurring somatostatin-14 and analogues having somatostatin related activity, e.g. as disclosed by A.S. Dutta in Small Peptides, Vol.19, Elsevier (1993). By the term "a somatostatin peptide" or "a somatostatin analogue" as used herein is meant any straight-chain or cyclic polypeptide having a structure based on that of the naturally occurring somatostatin-14 wherein one or more amino acid units have been omitted and/or replaced by one or more other amino radical(s) and/or wherein one or more functional groups have been replaced by one or more other functional groups and/or one or more groups have been replaced by one or several other isosteric groups. The terms a somatostatin and a somatostatin analogue are used within this disclosure as synonyms.
Highly surprisingly it was found that the above mentioned somatostatins, preferably octreotide, appear to maximize and / or preserve the function of the residual visual functions. Accordingly, the addressed somatostatins are highly useful in the treatment of glaucoma alone or in addition to ocular hypotensive agents or procedures. The benefit of said treatment is not dependant upon an effect on intraocular pressure (IOP). In summary, an addressed somatostatin, in particular octreotide, is highly useful in the treatment and / or prevention of ocular disorders, selected from the group consisting of: Vision loss due to progressive retinal and / or optic nerve diseases such as glaucoma, retinitis pigmentosa, diabetic macular edema and age related macular degeneration.
Within the context of the present invention the term treatment and / or prevention means the treatment and the prevention of a disorder, preferably the treatment or the prevention of a disorder, more preferably the treatment and in particular the prevention of a disorder.
Cyclic, bridge cyclic and straight-chain somatostatin analogues or derivatives are known and have been described together with processes for their production e.g. in US Patent 4,310,518.
Preferred somatostatin analogues are e. g. compounds of formula (I),
A; I 2 I
N-CH-ij-BCDE-NH-CH-G (I)
A' O
wherein
A is d.^alkyl, C7-10phenylalkyl or a group of formula RCO-, whereby i) R is hydrogen, Chalky!, phenyl or C7-ι0phenylalkyl, or ii) RCO- is
a) a D-phenylalanine residue optionally ring-substituted by halogen, NO2, NH2, OH, C-i-salkyl and/or Cι-3alkoxy; or
b) the residue of a natural or a synthetic α-amino-acid other than defined under a) above, or of a corresponding D-amino acid, or
c) a dipeptide residue in which the individual amino acid residues are the same or different and are selected from those defined under a) and/or b) above, the oc-amino group of amino acid residues a) and b) and the N-terminal amino group of dipeptide residues c) being optionally mono- or di-C1-12alkylated or substituted by Cι-8alkanoyl;
A' is hydrogen or C1-3alkyl,
Yi and Y2 represent together a direct bond or each of Yi and Y2 is hydrogen
B is -Phe- optionally ring-substituted by halogen, NO2, NH , OH, Cι-3alkyl and /or Cι-3alkoxy (including pentafluoroalanine), naphthylalanine or pyridylalanine,
C is (L)-Trp- or (D)-Trp- optionally a-N-methylated and optionally benzene- ring-substituted by halogen, NO2, NH2, OH, Cι-3alkyl and/or Cι-3alkoxy,
D is Lys, 4-aminocyclohexylAla or 4-aminocyclohexylGly
E is Thr, Ser, Val, Tyr, He, Leu or an aminobutyric or aminoisobutyric acid residue
G is a group of formula: -COOR7, -CH2OR10, -CONRnRι2or
R7 is hydrogen or Chalky!,
R10 is hydrogen or the residue of a physiologically acceptable, physiologically hydrolysable ester, R11 is hydrogen, Cι-3alkyl, phenyl or C7-ι0phenyl-alkyl, R12 is hydrogen, C1-3alkyl or a group of formula -CH(Rι3)-Xι, R13 is CH2OH, -(CH2)2-OH, -(CH2)3-OH, or -CH(CH3)OH or represents the substituent attached to the a-carbon atom of a natural or synthetic a-amino acid (including hydrogen) and ^ is a group of formula -COOR7, -CH2OR10 or -CO-NR14R15
wherein
R7 and R10 have the meanings given above,
R is hydrogen or Cι-3alkyl and
R15 is hydrogen, Cι-3alkyl, phenyl or C7-10phenylalkyl, and
R16 is hydrogen or hydroxy,
with the proviso that when R12 is -CH(R13)-X1 then Ru is hydrogen or methyl,
wherein the residues B, D and E have the L-configuration, and the residues in the 2- and 7-position each independently have the (L)- or (D)- configuration,
in free form or in pharmaceutically acceptable salt or complex form.
Individual compounds of formula I suitable in accordance with the present invention are the following somatostatin analogues:
(D)Phe-Cys-Phe-(D)Trp-Lys-Thr-Cys-Thr-ol also known as octreotide
b I >
(D)Phe-Cys-Tyr-(D)Trp-Lys-Val-Cys-ThrNH2
(D)Phe-Cys-Tyr-(D)Trp-Lys-Val-Cys-TrpNH2
also known as vapreotide
I I
(D)Trp-Cys-Phe-(D)Trp-Lys-Thr-Cys-ThrNH2
(D)Phe-Cys-Phe-(D)Trp-Lys-Thr-Cys-ThrNH2
f- 3-(2-(Naphthyl)-(D)Ala-Cys-Tyr-(D)Trp-Lys-Val-Cys-ThrNH2
also known as lanreotide
g- (D)Phe-Cys-Tyr-(D)Trp-Lys-Val-Cys-β-Nal-NH2
h.
3-(2-(Naphthyl)-(D)Ala-Cys-Tyr-(D)Trp-Lys-Val-Cys-β-Nal-NH 2
l.
(D)Phe-Cys-β-Nal-(D)Trp-Lys-Val-Cys-Thr-NH2
j' (D)Phe-Cys-Tyr-(D)Trp-Lys-Leu-Cys-Thr-NH2
k.
(D)Phe --CCyyss--TTyyrr--((DD))TTrrpp--LLvyss--CCys-Thr-NH2
More preferred compounds of formula (I) are compounds (a) - (k).
A highly preferred compound of formula (I) is octreotide.
Compounds of formula (I) may exist e.g. in free form, salt form or in the form of complexes thereof. Acid addition salts may be formed with e.g. organic acids, polymeric acids and inorganic acids. Such acid addition salt forms include e.g. the hydrochlorides and acetates. Complexes are e.g. formed from compounds of the invention on addition of inorganic substances, e.g. inorganic salts or hydroxides such as Ca- and Zn-salts, and/or an addition of polymeric organic substances.
Further somatostatin analogues suitable for use in accordance with the present invention are: cyclo [-Asn-Phe-Phe-DTrp-Lys-Thr-Phe-Gaba-j, cyclo(Asu-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Tyr-Thr-Ser), and
(D)Nal-Glu-Tyr-(D)Trp-Lys-Val-Lys-Thr-NH2
According to the invention, a somatostatin analogue is preferably administered in the form of a pharmaceutical composition, by any conventional route, in particular enterally, e.g. orally, e.g. in the form of tablets, capsules, drink solutions, emulsions or microemulsion preconcentrates, nasally, pulmonary (by inhalation), parenterally, e.g. in the form of injectable solutions or suspensions, in the form of an implant, such as for example a biodegradable polymer loaded with a somatostatin, or topically. A somatostatin analogue is preferably administered parenterally, typically subcutaneously and intramuscularily, e.g by injection and/or infusion. The somatostatin analogue may also be administered in a slow release form, e.g. as disclosed in UK Patent Specification 2,265,311 B.
The amount administered is determined taking into account various factors such as the etiology and severity of the disease, and the patient's condition. A somatostatin analogue may be administered, e.g. subcutaneously, in a dosage range of about 100 μg to 10 mg per day as a single dose or in divided doses. Thus octreotide may be administered at a dose of from 0.2 mg to 10 mg twice or three times daily. When administered as a slow release form, such formulation may comprise the somatostatin peptide in a concentration from 2.0 to 10% by weight. The release period of such a formulation may be from 1 week to about 2 months.
The invention contemplates that an active ingredient discussed herein may be utilized in combination with pharmaceutically acceptable diluents and carriers.
A. Formulation Examples:
1. Ampoules
Octreotide 0.5 mg
Mannitol 45.0 mg
Lactic acid (88%) 3.4 mg
Sodium hydrogencarbonate to pH 4.2
Water (inject.grade) to 1 ml
Carbon dioxide q.s.
iodegradable sustained release formulation
Octreotide Acetate 4.65 % (by weight)
Poly(DL-lactide-co-glycolide) 78.35 %
Sterile Mannitol 17 %
Vehicle: Carboxymethylcellulose 0.5 % (by weight)
Mannitol 0.6 %
Water for injection 98.9 %