PEPTIDE SLOW-RELEASE FORMULATIONS

Abstract

A composition for the delayed delivery of a peptide active agent comprising; i) a salt of said peptide active agent comprising at least one positively charged peptide ion and at least one negatively charged counter-ion ii) a sustained-release delivery vehicle, wherein the at least one negatively charged counter-ion is a halide ion, preferably a chloride or bromide ion.

Claims

1-37. (canceled)

38. A method for the treatment of a human or non-human mammalian subject in need thereof with a somatostatin analogue, comprising administering to the subject a pre-formulation comprising a low-viscosity mixture of: a) at least one diacyl glycerol; b) at least one phosphatidyl choline (PC); c) at least one oxygen containing organic solvent; and d) at least one halide salt of at least one somatostatin analogue selected from lanreotide and vapreotide; wherein the pre-formulation forms, or is capable of forming, at least one liquid crystalline phase structure upon contact with an aqueous fluid.

39. The method of claim 38, wherein component a) comprises glycerol dioleate (GDO).

40. The method of claim 38, wherein component b) comprises soy PC.

41. The method of claim 38, wherein component c) comprises ethanol.

42. The method of claim 38, wherein the halide salt is a chloride or bromide ion.

43. The method of claim 38, wherein the pre-formulation comprises: a) 40-70 wt % of the at least one diacyl glycerol; b) 30-60 wt % of the at least one phosphatidyl choline (PC); and c) 0.1-20 wt % of the at least one oxygen containing organic solvent.

44. The method of claim 38, wherein components a) and b) are present in a ratio of a:b of 40:60 to 70:30.

45. The method of claim 38, wherein the pre-formulation comprises: a) 40-70 wt % of glycerol dioleate (GDO); b) 30-60 wt % of soy PC; c) 0.1-20 wt % of ethanol; and d) 0.1-10 wt % of the at least one halide salt of at least one somatostatin analogue selected from lanreotide and vapreotide; wherein the halide salt is a chloride or bromide ion, wherein components a) and b) are present in a ratio of a:b of 40:60 to 70:30.

46. The method of claim 45, wherein the pre-formulation comprises: a) 43-60 wt % of glycerol dioleate (GDO); b) 35-55 wt % of soy PC; and c) 0.1-10 wt % of ethanol, wherein components a) and b) are present in a ratio of a:b of 45:55 to 60:40.

47. The method of claim 46, wherein the pre-formulation comprises: a) 45-55 wt % of glycerol dioleate (GDO); b) 40-50 wt % of soy PC; and c) 2-8 wt % of ethanol; wherein components a) and b) are present in a ratio of a:b of 48:52 to 55:45.

48. The method of claim 38, wherein the method of treatment is a method for the treatment of at least one condition selected from acromegaly, cancers, carcinomas, melanomas, tumours expressing at least one somatostatin receptor, somatostatin receptor-2-positive tumours, somatostatin receptor-5-positive tumours, prostate cancers, gastro-entero-pancreatic neuroendocrine tumours, carcinoid tumours, insulinomas, gastrinomas, vasoactive intestinal peptide—producing-tumours and glucagonomas, elevated growth hormone, elevated insulin-like growth factor I, varicial bleeding, chemotherapy induced gastro intestinal problems, lymphorrhea, diabetic retinopathy, thyroid eye disease, obesity, pancreatitis, and related conditions.

49. The method of claim 38, comprising administration by i.m., s.c. or preferably deep s.c. injection.

50. The method of claim 38, comprising administration by a pre-filled administration device.

51. The method of claim 38, comprising a single administration every 20 to 180 days.

Description

[0174] The invention will now be further illustrated by reference to the following non-limiting Examples and the attached Figures, in which;

[0175] FIG. 1 compares decreases in viscosity at 25° C. of the depot precursor on addition of solvents, including the addition of: EtOH to PC/GDO (50/50), represented by solid circles; PG to PC/GDO (50/50), represented by solid squares; N-methyl pyrolidinone (NMP) to PC/GDO (50/50), represented by solid diamonds; EtOH to PC/GDO (40/60), represented by open circles; PG to PC/GDO (40/60), represented by open squares; and NMP to PC/GDO (40/60), represented by open diamonds, and demonstrates the non-linear decrease of pre-formulation viscosity upon addition of NMP and EtOH. PC/GDO (50/50) is a precursor to a reversed hexagonal H.sub.II phase and PC/GDO (40/60) is a precursor to a reversed cubic I.sub.2 phase.

[0176] FIG. 2 shows in vitro release of octreotide (octreotide base (OCT(0)) over a 24 hour period at 37° C. at different formulation-to-PBS weight ratios from a formulation containing octreotide acetate (OCT(Ac)), represented by open squares, and from a formulation containing octreotide chloride (OCT(Cl)), represented by closed circles. Error bars represent standard deviation (n>2).

[0177] FIG. 3 shows the octreotide content (expressed as % of nominal content) as a function of storage time and temperature conditions for acetate and chloride formulations #174 and #192, respectively. FIG. 3 shows that changing the counter-ion from acetate (formulation #174) to chloride (formulation #192) results in a dramatic stability enhancing effect.

[0178] FIG. 4 shows the breakdown products detected by HPLC and expressed as % area at 215 nm for formulations containing octreotide acetate (formulation #174) and octreotide chloride (formulation #192). FIG. 4 shows that changing the counter-ion from acetate (formulation #174) to chloride (formulation #192) results in a dramatic stability enhancing effect.

EXAMPLES

Example 1

Availability of Various Liquid Crystalline Phases in the Depot by Choice of Composition

[0179] Injectible formulations containing different proportions of phosphatidyl choline (“PC”—Epikuron 200) and glycerol dioleate (GDO) and with EtOH as solvent were prepared to illustrate that various liquid crystalline phases can be accessed after equilibrating the depot precursor formulation with excess water.

[0180] Appropriate amounts of PC and EtOH were weighed in glass vials and the mixture was placed on a shaker until the PC completely dissolved to form a clear liquid solution. GDO was then added to form an injectible homogenous solution.

[0181] Each formulation was injected in a vial and equilibrated with excess water. The phase behaviour was evaluated visually and between crossed polarizes at 25° C. Results are presented in Table 1.

TABLE-US-00001 TABLE 1 Formulation PC (wt %) GDO (wt %) EtOH (wt %) Phase in H.sub.2O A 22.5 67.5 10.0 L.sub.2 B 28.8 61.2 10.0 I.sub.2 C 45.0 45.0 10.0 H.sub.II D 63.0 27.0 10.0 H.sub.II/L.sub.α L.sub.2 = reversed micellar phase I.sub.2 = reversed cubic liquid crystalline phase H.sub.II = reversed hexagonal liquid crystalline phase L.sub.α = lamellar phase

Example 2

Viscosity in PC/GDO (5:5) or PC/GDO (4:6) on Addition of Solvent (EtOH, PG and NMP)

[0182] A mixture of PC/GDO/EtOH with approximately 25% EtOH was manufactured according to the method in Example 1. All, or nearly all, of the EtOH was removed from the mixture with a rotary evaporator (vacuum, 40° C. for 1 h followed by 50° C. for 2 h) and the resulting mixture was weighed in a glass vial after which 1, 3, 5, 10 or 20% of a solvent (EtOH, propylene glycol (PG) or n-methyl pyrrolidone (NMP)) was added. The samples were allowed to equilibrate several days before the viscosity was measured with a CarriMed CSL 100 rheometer equipped with automatic gap setting.

[0183] This example clearly illustrates the need for solvent with certain depot precursors in order to obtain an injectable formulation (see FIG. 1). The viscosity of solvent-free PC/GDO mixtures increases with increasing ratio of PC. Systems with low PC/GDO ratio (more GDO) are injectable with a lower concentration of solvent.

Example 3

Preparation of Depot Composition Containing the Peptide Octreotide

[0184] Octreotide acetate (24 mg or 60 mg) was dissolved in 0.1 g EtOH. 0.36 g PC and 0.54 g GDO were subsequently dissolved in this solution and a depot formulation precursor was obtained. Injecting the formulation precursor into excess aqueous phase (syringe 23G; 0.6 mm×30 mm) resulted in a monolithic liquid crystalline phase (I.sub.2 structure). I.e. octreotide (2.4% or 6.0%) did not change monolith formation and phase behaviour after exposure to an aqueous environment.

[0185] The octreotide depot precursor formulations in this Example were tested for stability against crystallization during storage. Each formulation was stable at 4-8° C. for at least two weeks.

Example 4

Preparation of Octreotide Chloride Salt

[0186] Octreotide chloride (OCT(Cl)) was prepared from Octreotide acetate (OCT(Ac)) by running an aqueous solution of OCT(Ac) through an ion-exchange column, pre-packed with the anion-exchange resin Dowex 1×2 (Fluka) and pre-equilibrated with water for injection (WFI). The adequate fractions of OCT(Cl) in WFI were identified by measuring the conductivity of the collected fractions. These fractions were pooled and the sample was lyophilized by freeze-drying overnight giving the OCT(Cl) as a white powder.

Example 5

Octreotide Acetate and Octreotide Chloride Compositions

[0187] Liquid crystalline formulations of OCT(Ac) and OCT(Cl) were prepared in the following way: Soy phosphatidylcholine (SPC—Lipoid S100 from Lipoid, Germany), glycerol dioleate (GDO—from Danisco, Denmark), ethanol (EtOH 99.5%) and OCT(Ac) (PolyPeptide Labs, CA, USA) or OCT(Cl) (as prepared in Example 4) were mixed in excess EtOH until a homogenous liquid mixture was obtained. The EtOH content was thereafter adjusted to 5 wt % by rotary evaporation of the excess solvent. The sample compositions are given in the Table below:

[0188] Formulation compositions in wt %.

TABLE-US-00002 Formulation# OCT(Ac) OCT(Cl) SPC GDO EtOH 186 3 — 46 46 5 183 — 3 46 46 5

[0189] The in vitro release was determined by first placing a sample of the respective formulation (0.1-0.4 g) in a well of a 96-deep-well plate. After allowing the liquid octreotide formulation to settle in the bottom of the well for a few minutes, phosphate buffered saline (PBS) was added in different amounts (0.2-1 mL) to achieve the required conditions with respect to the formulation-to-aqueous medium weight ratio (from formulation in excess to PBS in excess). The 96-well plate was thereafter put on a shaking table held at 37° C. and with low rotating speed (150 rpm). After 24 hours, PBS samples from the respective wells were withdrawn and the octreotide content (in terms of octreotide base=OCT(0)) in the aqueous release medium was analyzed by HPLC. At least two replicates (wells) for each formulation-to-PBS ratio and for each formulation were analyzed.

[0190] The results are shown in FIG. 2 as % octreotide (octreotide base=OCT(0)) released from the respective formulation as a function of formulation-to-PBS weight ratio. It is clear from FIG. 2 that under all the investigated conditions in terms of formulation-to-PBS weight ratios, the release of octreotide from the formulation containing OCT(Ac) is markedly higher than for the corresponding OCT(Cl) formulations. This fact is highly surprising considering that only the peptide counter-ion (acetate versus chloride) differs between the formulations. The effects observed are essentially independent of the PBS to formulation ratio and are of particular interest for a long-acting release depot product of octreotide (e.g. 1 month or longer duration) where a slow release of the peptide active agent is a pre-requisite.

Example 6

Stability of Octreotide in LC Depot Formulation—Comparison Between Octreotide Acetate (OCT(Ac)) and Octreotide Chloride (OCT(Cl))

[0191] Experimental Details

[0192] LC formulations of OCT(Ac) and OCT(Cl) were prepared as described above in Example 5. (OCT(Cl) was prepared from OCT(Ac) by ion-exchange column chromatography—see Example 4). The compositions of the formulations are given in the Table below. The formulations were stored in glass vials with Teflon®-coated rubber stoppers in a climate chamber (Termak) at 40° C./75% relative humidity. The octreotide content (expressed as % of nominal content), ID and related substances were determined by HPLC with UV detection at 215 nm.

[0193] Nominal formulation compositions in wt %.

TABLE-US-00003 OCT(Ac) OCT(Cl) Formulation# [OCT(0)] [OCT(0)] SPC GDO EtOH 174 4.8 45.0 45.0 5.1 [4.1] 192 5.5 44.7 44.7 5.1 [4.9]

[0194] Results

[0195] The octreotide content, expressed as % of nominal concentration (see Table 2), as a function of storage time and condition is shown in FIG. 3. The effect of changing the counter-ion from acetate to chloride is unexpectedly high. Whereas little change occurs for the OCT(Cl) formulation (#192) after 4 weeks at 40° C., a marked degradation of octreotide in the OCT(Ac) formulation (#174) takes place. This is even more clearly seen in FIG. 4 where the amount of breakdown products (expressed as % of the total Peak Area at 215 nm UV detection) is displayed as a function of storage time and condition. In conclusion, the stability enhancing effect of the chloride counter-ion is surprisingly high which is extremely beneficial from a storage stability perspective of a depot formulation product of octreotide.

Example 7

Further Examples of Viscosity in PC/GDO Mixtures on Addition of Co-Solvent

[0196] Mixtures of PC/GDO and co-solvent were prepared according to the methods of Example 1 and Example 2 in the proportions indicated in the table below.

[0197] The samples were allowed to equilibrate for several days before viscosity measurements were performed using a Physica UDS 200 rheometer at 25° C.

TABLE-US-00004 PC/GDO EtOH/ Glycerol/ H.sub.2O/ Viscosity/ Sample (wt/wt) wt % wt % wt % mPas 1 50/50 3 — — 1900  2 50/50 5 — — 780 3 50/50 7 — — 430 4 50/50 8 — — 300 5 50/50 10 — — 210 6 50/50 15 — — 100 7 45/55 3 — — 1350  8 45/55 5 — — 540 9 45/55 7 — — 320 10 45/55 8 — — 250 11 45/55 10 — — 150 12 45/55 15 — —  85 13 40/60 3 — — 740 14 40/60 5 — — 400 15 40/60 7 — — 240 16 40/60 8 — — 200 17 40/60 10 — — 130 18 40/60 15 — —  57 19 40/60 — 10 — 8*10.sup.6 20 40/60 — — 3 2.5*10.sup.8   21 40/60 — — 5 4*10.sup.7

[0198] This example further illustrates the need for a solvent with viscosity lowering properties in order to obtain injectable formulations. The mixtures containing glycerol (sample 19) or water (samples 20 and 21) are too viscous to be injectable at solvent concentrations equivalent to the samples containing EtOH (compare with samples 13, 14 and 17).