Treprostinil for the treatment of pulmonary hypertension

Abstract

The present invention provides treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method of treating pulmonary hypertension in a subject diagnosed with or at risk of developing pulmonary hypertension, the treatment comprising the steps of: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; and ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period, wherein the second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is higher than the first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition, and wherein the first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

Description

[Technical field]

[0001] The present invention relates to methods, compositions and kits for inhalation administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof.Furthermore, the present invention relates to a pharmaceutical preparation comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the treatment of pulmonary hypertension, and a kit comprising solutions of treprostinil with different concentrations. [Background technology]

[0002] Pulmonary hypertension is a medical condition in which blood pressure in the blood vessels of the lungs increases. Symptoms include shortness of breath, loss of consciousness, fatigue, chest pain, swelling in the legs and increased heart rate.

[0003] According to the WHO classification, there are five pulmonary hypertension groups, and these groups can be further divided into subgroups.For example, WHO group I refers to pulmonary arterial hypertension (PAH), while WHO group III refers to pulmonary hypertension caused by lung disease (such as chronic obstructive pulmonary disease, COPD) or chronic hypoxia.As a further example, WHO group IV refers to chronic arterial obstruction.

[0004] Depending on the specific group or type of pulmonary hypertension diagnosed in a patient, there are several surgical and pharmaceutical therapeutic approaches available, the latter including administration of vasoactive substances, such as endothelin receptor antagonists, phosphodiesterase type 5 inhibitors, activators of soluble guanylate cyclase and prostaglandins or prostanoid analogues. An example of a stable prostanoid analogue that has been used to treat pulmonary hypertension is treprostinil, which can be administered by intravenous or subcutaneous injection. Administration of treprostinil by intravenous injection may be associated with an increased risk of infection and sepsis, while administration of treprostinil by subcutaneous injection has been reported to be associated with significant pain. Therefore, as an alternative, formulations of treprostinil for inhalation administration have been developed.

[0005] US Patent Publication No. 2020 / 0171044 discloses a method of treating pulmonary hypertension comprising administering to a human suffering from pulmonary hypertension a therapeutically effective single event dose of a formulation comprising treprostinil or a pharma- ceutically acceptable salt thereof by inhalation in one to three breaths using a particular inhalation device at a dose of 15-90 μg. The administered formulations have a concentration of treprostinil of 1 mg / mL or 2 mg / mL, respectively.

[0006] R. Voswinkel et al. Disclose in Pulmonary Pharmacology & Therapeutics 22 (2009), p, 50-56 disclose the administration of treprostinil in doses of 30, 45 and 60 μg in the form of a liquid formulation having concentrations of 1 mg / mL and 2 mg / mL in two or three breaths using a specific inhalation device.

[0007] KS Parikh et al. report in J. Cardiovasc. Pharmacol., Vol. 67, Number 4, p. 322-325 that a complex titration algorithm initially delivers 3 breaths, followed by 6 breaths, and finally a maximum of 12 breaths containing 72 μg of treprostinil 4 times a day, with each breath delivering a fixed amount of 6 μg of treprostinil.

[0008] A pharmaceutical product for inhalation containing treprostinil in the form of a solid dry powder (TYVASO DPI™, United Therapeutics Corp.) has been approved in the United States. However, administration of dry powder has several disadvantages, including ia, complex handling due to different dry powder formulations provided in different containers, specific storage conditions and short storage times of the dry powder formulations, and a significant amount of waste.

[0009] Similarly, a complex dosing scheme has been developed for the only commercially available medication for inhalation containing treprostinil in liquid form (TYVASO®, United Therapeutics Corp.), in which the product is administered in four separate, equally spaced treatment sessions per day. In the initial phase of therapy, the product is administered by three breaths of product four times per day. This dosage is increased by an additional three breaths at biweekly intervals to a target dose of nine breaths per treatment session applied four times per day.

[0010] These complex dosing regimens inherently carry the risk of over- or under-dosing due to human error, since the exact number of successively increasing inhalation breaths must be counted and recorded, or the correct container must be identified, which places a significant burden on patients, especially in cases of severe illness and those with significant functional limitations, as well as on medical staff when necessary. Furthermore, due to the frequent application with multiple daily inhalations, including up to 12 inhalation breaths, these protocols and dosing schemes cause significant inhalation times that may lead to poor patient compliance and patient withdrawal from treatment. In addition, multiple successive inhalation maneuvers may result in secondary adverse effects such as coughing, sore throat, etc.

[0011] It is therefore an object of the present invention to provide a method for inhalation administration of treprostinil, which allows for the implementation of a simplified administration scheme during all stages of treatment, if possible, and thus reduces the risk of over- or under-dosing by shortening the overall daily inhalation time, and therefore reduces the burden on patients requiring such treatment when implementing the necessary inhalation scheme. Further objects of the present invention will become apparent based on the following description of the invention, the examples, and the claims. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] US Patent Application Publication No. 2020 / 0171044 [Non-patent literature]

[0013] [Non-Patent Document 1] R. Voswinkel et al. Disclose in Pulmonary Pharmacology&Therapeutics 22(2009), p, 50~56 [Non-Patent Document 2] KSParikh et al.report in J.Cardiovasc.Pharmacol.,Vol.67,Number 4,p.322~325 Summary of the Invention

[0014] In a first aspect, the present invention relates to a method for inhaled administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof to a subject in need of such administration, the method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0015] In a further aspect, the present invention provides a medicament comprising treprostinil or a pharma- ceutical agent comprising treprostinil or a pharma- ceutical agent for use in the treatment of pulmonary hypertension in a subject diagnosed with pulmonary hypertension or for use in the prevention of pulmonary hypertension in a subject at risk of developing pulmonary hypertension, the treatment or prevention comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0016] In a third aspect, the present invention provides a method for producing a pharmaceutical composition comprising the steps of: a) a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; b) a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, and, optionally, c) a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; d) a soft mist inhaler; The second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is higher than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition, and the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the optional third liquid composition is higher than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 shows the droplet size distribution (DSD) curves generated when aerosolizing a 1 mg / mL aqueous solution of treprostinil using an impaction soft mist inhaler. [Diagram 2] 1 shows the DSD curves generated when aerosolizing a 1 mg / mL aqueous solution of Treprostinil using an impaction soft mist inhaler. Results presented are the average DSD over 120 device actuations. [Diagram 3] FIG. 1 shows the DSD curve generated when a 5 mg / mL aqueous solution of treprostinil was aerosolized using an impaction soft mist inhaler. [Figure 4] FIG. 1 shows the DSD curve generated when a 5 mg / mL solution of treprostinil in water / ethanol (50% / 50% (v / v)) was aerosolized using an impaction soft mist inhaler. [Diagram 5] FIG. 1 is a cross-sectional view of an impingement soft mist inhaler with a container inserted. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The present inventors have developed a significantly improved and simplified method for inhalation administration of Treprostinil or its pharma- ceutically acceptable salt or derivative using a soft mist inhaler. The novel administration method is based on using multiple liquid compositions containing different concentrations of Treprostinil or its pharma- ceutically acceptable salt or derivative, which are administered by inhalation using a soft mist inhaler. The new and improved administration method is particularly suitable for the treatment of pulmonary hypertension, allowing easier dosing and administration protocols, while increasing the dosage of Treprostinil or its pharma-ceutically acceptable salt or derivative over time and over several titration treatment steps. The advantages of the method of the present invention include, but are not limited to, for example, a) reduced respiratory rate per administration, b) a more convenient and easier application regimen to follow (by maintaining the same pharma- ceutical dose throughout all treatment steps), and c) easier transition to the next dosage level (and consequently the next transition step). Further advantages of the methods of the present invention include, but are not limited to, improved stability profiles (especially when compared to dry powder formulations), advantageous storage requirements, and significantly improved applicability (e.g., regardless of the actual orientation or position of the subject).

[0019] The term "treatment", as used herein, unless otherwise specified, means administration of a compound or composition to a subject to at least ameliorate, reduce or inhibit existing signs or symptoms of a disease, disorder or condition, specifically pulmonary hypertension, experienced by the subject.

[0020] The term "prevention," as used herein, unless otherwise specified, refers to the prophylactic administration of a compound or composition to a subject that does not exhibit signs or symptoms of a disease, disorder, or condition, specifically pulmonary hypertension, but is expected or anticipated to be likely to exhibit such signs or symptoms in the absence of prevention. Prophylactic treatment may at least reduce or partially ameliorate the expected symptoms or symptoms.

[0021] As used herein, unless otherwise specified, the term "aerosolize" refers to converting a liquid or liquid composition into droplets of such liquid or liquid composition that are small and light enough to be carried on the air to form an aerosol. Thus, as used herein, the term "aerosolize" or "aerosolized" refers to the process by which a liquid or liquid composition is converted into an aerosol and the result of such a process.

[0022] The term "effective amount" as used herein refers to administration of a sufficient amount of the relevant compound or composition to prevent the onset of symptoms of the condition being treated, or to stop the worsening of symptoms, or to treat and alleviate symptoms, or at least reduce the severity of symptoms. Effective amounts vary as understood by those skilled in the art depending on the age, sex, weight, etc. of the patient.

[0023] As used herein, the term "event", unless otherwise specified, means a treatment session in which a dose of the relevant compound is administered to / inhaled by a subject, although a treatment session may include one or more actuations of a soft mist inhaler.

[0024] The term "dose" as used herein, unless otherwise specified, means the amount of the relevant compound administered to a subject in a single event.

[0025] As used herein, unless otherwise specified, the term "treatment period" refers to the period of time during a treatment phase during which a subject receives a liquid composition comprising a particular concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form.

[0026] The term "subject" or "individual" or "patient" as used herein, unless otherwise specified, may refer to any subject for whom therapy is desired, particularly a vertebrate subject, and even more particularly a mammalian subject. Suitable vertebrates include, but are not limited to, primates, birds, livestock animals (e.g., sheep, cows, horses, donkeys, pigs), laboratory animals (e.g., rabbits, mice, rats, guinea pigs, hamsters), companion animals (e.g., cats, dogs) and captive wild animals (e.g., foxes, deer, dingoes). A preferred subject, individual or patient is a human, e.g., a male or female, particularly an adult male or female at least 16 years of age or at least 18 years of age, e.g., 18 years to about 90 years of age or about 30 years to about 80 years of age or about 40 years to about 75 years of age.

[0027] Treprostinil (2-[[(1R,2R,3aS,9aS)-2-hydroxy-1-[(3S)-3-hydroxyoctyl]-2,3,3a,4,9,9a-hexahydro-1H-cyclopenta[g]naphthalen-5-yl]oxy]acetic acid; CAS number 81846-19-7) has a molecular weight of 390.52 g / mol and the chemical structure shown in the following formula (I,R=H): [ka]

[0028] The most important pharma- ceutically acceptable salts include, but are not limited to, treprostinil sodium (R = Na) and treprostinil diolamine (treprostinil diethanolamine, R = H2N(C2H4OH)2). Furthermore, the pharma- ceutically acceptable derivatives of treprostinil referred to herein include carboxylic acid esters of treprostinil (sometimes also referred to as "ester prodrugs" of treprostinil of formula (I) where R is an aliphatic hydrocarbon residue, preferably a saturated unbranched hydrocarbon residue, having 1 to about 25 carbon atoms, or about 6 to about 20 carbon atoms, or about 12 to about 20 carbon atoms), e.g., R = (CH2) 15 These include, but are not limited to, treprostinil palmitate of formula (I) where is CH3.

[0029] According to a first aspect, the present invention relates to a method for inhaled administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof to a subject in need of such administration, the method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0030] The method of the present invention is particularly suitable for treating pulmonary hypertension. Thus, in one embodiment, the present invention relates to the method as defined above, in which the subject to be treated is diagnosed with pulmonary hypertension. In a particular embodiment, the method as defined above is a method for treating pulmonary hypertension. In some embodiments, pulmonary hypertension can be idiopathic or primary hypertension, in other words, pulmonary hypertension of unknown etiology or hereditary pulmonary hypertension. In other embodiments, pulmonary hypertension can be secondary pulmonary hypertension resulting from known risk factors or underlying diseases, such as chronic hypoxia, chronic obstructive pulmonary disease (COPD), interstitial lung disease, connective tissue disease, portal hypertension, congenital heart disease, HIV infection, alveolar hypoventilation, etc. Thus, in a particular embodiment, the subject to be treated according to the present invention suffering from or at risk of developing pulmonary hypertension is diagnosed with (pre-existing or intercurrent) pulmonary and cardiac disease or other risk factors as described above.

[0031] In some embodiments, the pulmonary hypertension is pulmonary arterial hypertension, particularly pulmonary arterial hypertension as defined by WHO Group I pulmonary hypertension, in other embodiments, the pulmonary hypertension is pulmonary hypertension associated with WHO Group III interstitial lung disease (PH-ILD).

[0032] In addition to the method according to the first aspect of the invention as defined above, in a second aspect the invention relates to a medicinal product comprising treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use in the treatment of pulmonary hypertension in a subject diagnosed with pulmonary hypertension or for use in the prevention of pulmonary hypertension in a subject at risk of developing pulmonary hypertension, the treatment or prevention comprising i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0033] In a third aspect, the present invention further relates to treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, for use in a method for treating pulmonary hypertension in a subject diagnosed with pulmonary hypertension or for use in a method for preventing pulmonary hypertension in a subject at risk of developing pulmonary hypertension, the method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0034] In a fourth aspect, the present invention provides a method of treating pulmonary hypertension in a subject diagnosed with pulmonary hypertension or preventing pulmonary hypertension in a subject at risk of developing pulmonary hypertension, the method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

[0035] The embodiments of the invention discussed below apply respectively to the methods of the invention, to medicaments or treprostinil for use in a method of treating pulmonary hypertension as defined above, and to kits as further defined below.

[0036] In certain embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is sufficient such that the dosage required during the first treatment period can be administered in a small number of inhalation breaths required to inhale a complete dose (administered during the first treatment period), e.g., about 1 to about 3 breaths, or about 2 or 3 breaths, or 1 breath by inhalation.

[0037] In further specific embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is sufficient so that the dosage required during the second treatment period can be administered in a small number of inhalation breaths required for inhalation of a complete dose, for example, about 1 to about 3 breaths by inhalation, or about 2 to 3 breaths or 1 breath. In still further specific embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the optional third liquid composition is sufficient so that the dosage required during the optional third treatment period can be administered in a small number of inhalation breaths required for inhalation of a complete dose, for example, about 1 to about 3 breaths by inhalation, or about 2 or 3 breaths or 1 breath.

[0038] Preferably, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is about 1.5 to about 2.5 times or about 1.75 to about 2.25 times higher than that in the first liquid composition, or in other words, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is about 50% to about 150% or about 75% to about 125% higher than that in the first liquid composition. In a particular embodiment, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is about twice that of the first liquid composition.

[0039] A common therapy for pulmonary hypertension involves slowly increasing the dosage of treprostinil or a pharma- ceutically acceptable salt or derivative thereof (the so-called "titration" effect) until treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered at a final maintenance dose, which is usually the third dose but may also be the second dose.

[0040] Thus, in a preferred embodiment, the present invention relates to a method or a medicament for use in the method defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating pulmonary hypertension as defined above, iii) administering a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form during a third treatment period after the second treatment period; a third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the third liquid composition that is greater than a second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition; The third liquid composition is aerosolized and administered to the subject using a soft mist inhaler.

[0041] In certain embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the third liquid composition is about 2 to about 4 or about 2.5 to about 3.5 times higher than that in the first liquid composition, or in other words, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the optional third liquid composition is about 100% to about 300% or about 150% to about 250% higher than that in the first liquid composition.

[0042] In still further embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is from about 150% to about 250%, or from about 175% to about 225%, or from about 190% to about 210% compared to the amount present in the first liquid composition.

[0043] In still further embodiments, the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the optional third liquid composition is from about 200% to about 400%, or from about 250% to about 350%, or from about 290% to about 310% compared to the amount present in the first liquid composition.

[0044] In some embodiments, the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the third liquid composition is about three times the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof.

[0045] The advantage of the present invention is that the number of breaths required during inhalation is significantly reduced compared to the present treatment method, which requires up to 9 or even up to 12 breaths when the maintenance dose of treatment is reached. Moreover, in some embodiments, the method according to the present invention allows to maintain the same podiatry of administration of the entire dose administered with one actuation of the soft mist inhaler per event during one treatment session, in other words, the entire treatment. By using a liquid composition having a first concentration, a second concentration and an optional third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, it is possible to significantly reduce the number of breaths during the inhalation process. Preferably, the method and other aspects of the present invention include that the liquid composition is administered with the same number of breaths for the first, second and optional third liquid compositions. In certain embodiments of the present invention, the method includes aerosolizing the first, second and optional third liquid compositions, administering them using a soft mist inhaler, and administering them with one breath (respectively) per dose.

[0046] However, in further embodiments, the dose of Treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered to the subject may be increased during the treatment period. In these cases, the (increased) dose of Treprostinil or a pharma- ceutically acceptable salt or derivative thereof may be administered by increasing the number of actuations of the soft mist inhaler per event.

[0047] In further specific embodiments, the methods and other aspects of the present invention include that the first, second and optional third liquid compositions are aerosolized and administered using the same soft mist inhaler, with the term "same" as used in this context referring to the very same soft mist inhaler or different specimens of the same soft mist inhaler. This has proven particularly beneficial and surprising as the generation of aerosols of the first, second and optional third liquid compositions containing significantly different (increasing) amounts of dissolved treprostinil or a pharma- ceutically acceptable salt or derivative thereof, which was unexpected in view of the differing physicochemical properties of these liquid compositions.

[0048] The (absolute) concentrations of treprostinil or a pharma- ceutically acceptable salt or derivative thereof of the first, second and optional third concentrations should be sufficient to provide a sufficient amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof over several breaths, e.g. about 1 to about 5 or about 4 or about 3 breaths, preferably over one breath, for administration of one dose, when administered using a soft mist inhaler.

[0049] Thus, in certain embodiments, the present invention relates to a method or a medicament for use in the method defined above, or a method for treating or preventing pulmonary hypertension defined above, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1 mg / mL to about 5 mg / mL or about 3 mg / mL. In some embodiments, the first concentration is selected within the range of about 0.8 mg / mL to about 2 mg / mL or about 1 mg / mL to about 2 mg / mL. In certain embodiments, the first concentration is selected within the range of about 1.2 mg / mL to about 1.9 mg / mL or about 1.4 mg / mL to about 1.8 mg / mL, preferably about 1.5 mg / mL to about 1.7 mg / mL, for example about 1.6 mg / mL.

[0050] In further particular embodiments, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is selected within the range of about 1.6 mg / L to about 6 mg / mL, or about 2 mg / mL to about 6 mg / mL. Preferably, as outlined above, the concentration of treprostinil in the second liquid composition is about twice that of the first liquid composition. In some embodiments, the concentration of the second liquid composition is selected within the range of about 1.6 mg / mL or about 1.8 mg / mL or about 2 mg / mL to about 3.8 mg / mL or about 4 mg / mL. In particular embodiments, the concentration is within the range of about 2.8 mg / mL to about 3.6 mg / mL, preferably about 3 mg / mL to about 3.4 mg / mL, for example about 3.2 mg / mL.

[0051] In further particular embodiments, the present invention relates to a method or a medicament for use in the method defined above, or to a treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the optional third liquid composition is selected within the range of about 2.4 mg / mL to about 9 mg / mL or about 3 mg / mL to about 9 mg / mL. Preferably, as outlined above, the concentration of treprostinil in the optional third liquid composition is about three times that of the first liquid composition. In some embodiments, the concentration of the third liquid composition is selected within the range of about 2.4 mg / mL to about 6 mg / mL or about 2.6 mg / mL or about 2.8 mg / mL or about 3 mg / mL to about 6 mg / mL. In certain embodiments, the concentration of treprostinil in the optional third liquid composition is selected within the range of about 3.2 mg / mL to about 5.0 mg / mL, preferably about 4.2 mg / mL to about 5.0 mg / mL, for example 4.9 mg / mL.

[0052] In certain embodiments, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1 mg / mL to about 3 mg / mL, and the concentration of treprostinil in the second liquid composition is about twice that of treprostinil in the first liquid composition. In some embodiments, the method or medicament comprises an optional third liquid composition defined above, and the concentration of treprostinil in the third liquid composition is about three times that of treprostinil in the first liquid composition.

[0053] In a particular embodiment, the present invention relates to a method or a medicament for use in a method as defined above, or to a treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension as defined above, the method comprising: i) administering to a subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period, and, optionally, iii) administering a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form during a third treatment period after the second treatment period; The concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1.2 mg / mL to about 1.9 mg / mL or about 1.5 mg / mL to about 1.7 mg / mL, the concentration of treprostinil or a pharma-ceutically acceptable salt or derivative thereof in the second liquid composition is selected within the range of about 2.4 mg / mL to about 3.8 mg / mL or about 3 mg / mL to about 3.4 mg / mL, or is about twice the concentration of treprostinil or a pharma-ceutically acceptable salt or derivative thereof in the first composition, and the concentration of treprostinil or a pharma-ceutically acceptable salt or derivative thereof in the optional third liquid composition is selected within the range of about 3.6 mg / mL to about 5.7 mg / mL or about 4.2 mg / mL to about 4.9 mg / mL, or is about three times the concentration of treprostinil or a pharma-ceutically acceptable salt or derivative thereof in the first composition.

[0054] In some embodiments, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event (i.e., in a single actuation of a soft mist inhaler) during the first treatment period is selected in the range of about 10 μg to about 25 μg, preferably about 15 μg to about 20 μg. In these embodiments, the first liquid composition is preferably aerosolized in an amount of about 8.8 μL to about 13.3 μL when provided at a concentration of about 1.5 to about 1.7 mg / mL. In certain embodiments, the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the first treatment period is about 18 μg.

[0055] In some embodiments, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the second treatment period is selected in the range of about 25 μg to about 50 μg, preferably about 30 μg to about 40 μg. In these embodiments, the second liquid composition is preferably administered in an amount of about 8.8 μL to about 13.3 μL when aerosolized and provided at a concentration of about 3.0 to about 3.4 mg / mL. In certain embodiments, the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the second treatment period is about 36 μg.

[0056] In some embodiments, the present invention relates to a method or medicament for use in the method defined above, or to a treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the optional third treatment period is selected in the range of about 40 μg to about 70 μg, preferably about 45 μg to about 60 μg. In these embodiments, the optional third liquid composition is preferably aerosolized and administered in an amount of about 8.8 μL to about 13.3 μL when provided at a concentration of about 4.5 to about 4.9 mg / mL. In certain embodiments, the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the optional third treatment period is about 54 μg.

[0057] In some embodiments the invention relates to a method or medicament for use in a method as defined above or a method for treating or preventing pulmonary hypertension as defined above, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the first, second and optional third treatment periods as defined above is administered in one breath, respectively, upon a single actuation of a soft mist inhaler from which a single metered dose of treprostinil or a pharma- ceutically acceptable salt or derivative thereof is dispensed.

[0058] In general, in the treatment or prevention of pulmonary hypertension, Treprostinil or its pharma- ceutically acceptable salt or derivative is often administered four times a day (i.e., in four events), usually with about four hours between each administration. Thus, the total daily dosage of Treprostinil or its pharma-ceutically acceptable salt or derivative is about four times the dosage of a single dose administered in a single event.

[0059] Thus, in some embodiments, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during a first treatment period at a daily dose selected within the range of about 40 μg to about 100 μg, such as about 60 μg to about 80 μg. In a particular embodiment, treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during a first treatment period at a daily dose of about 72 μg.

[0060] In a further embodiment, the present invention relates to a method or a medicament for use in the method defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the second treatment period at a daily dose selected within the range of about 100 μg to about 200 μg or about 130 μg to about 170 μg. In a particular embodiment, Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the second treatment period at a daily dose of about 144 μg.

[0061] In yet a further embodiment, the present invention relates to a method or medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, wherein treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during an optional third treatment period at a daily dose selected within the range of about 160 μg to about 280 μg or about 200 mg to about 240 μg. In a particular embodiment, treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the third treatment period at a daily dose of about 216 μg.

[0062] The first and second treatment periods defined above usually last for about two weeks before reaching a final, third treatment period, which is considered a maintenance period and usually continues indefinitely.

[0063] Thus, in some embodiments, the present invention relates to a method or medicament for use in a method as defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension as defined above, wherein the duration of the first treatment period is selected within the range of about 1 day to about 15 days. In some embodiments, the duration of the first treatment period is at least about 10 days, preferably 10 or 12 to 15 days, in particular 14 days.

[0064] The duration of the second treatment period is, in some embodiments, approximately the same length as the first treatment period. Thus, in some embodiments, the invention relates to a method or medicament as defined above, wherein the duration of the second treatment period is selected within the range of about 1 day to about 15 days. In some embodiments, the duration of the second treatment period is at least about 10 days, preferably 10 or 12 to 15 days, in particular 14 days.

[0065] In some embodiments, the second treatment period can be extended and then become a maintenance period according to the specific needs of the particular subject to be treated.In these cases, there is no third treatment period.However, preferably, the method or medicament for use in the above-defined method comprises a third treatment period, which is a maintenance period.Said maintenance period can continue indefinitely or as long as such treatment is required by the subject.

[0066] The liquid composition comprising Treprostinil or its pharmaceutically acceptable salt or derivative can be any suitable pharmaceutically acceptable liquid composition suitable for inhalation using soft mist inhaler.The composition can be 100% aqueous or alcohol-based, especially ethanol-based.The composition used in the present invention can contain any suitable excipient, adjuvant, stabilizer and preservative or can be free of them.

[0067] Thus, in one embodiment the invention relates to a method or medicament for use in the method defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension defined above, wherein the first, second and optional third liquid compositions each comprise a liquid vehicle in which Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is dissolved.

[0068] In certain embodiments, the liquid vehicle may comprise one or more inorganic or organic solvents, preferably solvents that are physiologically acceptable and considered acceptable for pulmonary application by inhalation. In some embodiments, the liquid vehicle of the first, second or third liquid composition may each be an aqueous solution comprising an aqueous solvent or a mixture of solvents. Suitable solvents include water, ethanol, propylene glycol, and binary or tertiary mixtures thereof. In some embodiments, the liquid composition may comprise, as the liquid vehicle, a mixture of water and an alcohol, such as ethanol or propylene glycol, preferably ethanol, such as a mixture comprising about 99% (v / v) to about 1% (v / v) or about 95% (v / v) to about 10% (v / v) or about 90% (v / v) to about 50% (v / v) of water and a corresponding amount (added to 100% (v / v)) of alcohol, preferably ethanol. In certain embodiments, the liquid composition comprises water (without further inorganic or organic solvents) as the liquid vehicle.

[0069] In further specific embodiments, the first and second liquid compositions and the optional third liquid composition may all have the same liquid vehicle.However, in further embodiments, two of the three liquid compositions, for example the first and second liquid compositions, may have the same or substantially the same liquid vehicle, and one of the three liquid compositions, for example the third liquid composition, may have a different liquid vehicle, for example comprising different solvents or the same solvent in different ratios.In yet further specific embodiments, in some cases, two or all of the three liquid compositions may have different liquid vehicles, for example comprising different solvents or the same solvent in different ratios.

[0070] In some embodiments, the first, second and optional third liquid composition of the method or medicament for use in the method defined above further comprises one or more pharmaceutically acceptable excipients. Considering the pH-dependence of the solubility of Treprostinil or its salt in aqueous solvent system, the first, second and optional third liquid composition may comprise a pharmaceutically acceptable buffer, such as sodium citrate or others known to those skilled in the art. For long-term stability of the medicament, a pharmaceutically acceptable chelating agent, such as EDTA, may also be included. In addition, the first, second and optional third liquid composition may comprise a pharmaceutically acceptable preservative, for example a cationic surfactant, such as benzalkonium chloride (because the product is intended to be multi-dose sterilized).

[0071] Treprostinil can be used as free acid or in the form of its pharmaceutically acceptable salt or derivative.Suitable salt or derivative of Treprostinil is known to those skilled in the art, and includes but is not limited to Treprostinil sodium and Treprostinil diethanolamine as described above.Suitable derivative of Treprostinil includes but is not limited to Treprostinil carboxylic acid ester, such as Treprostinil palmityl as described above.Preferably Treprostinil is used in the same form during any treatment period.

[0072] Thus, in a particular embodiment, the present invention relates to a method or a medicament for use in the method defined above, or to treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension defined above, or to a kit defined below, wherein the treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first, second and optional third liquid composition is treprostinil sodium or treprostinil diethanolamine (diolamine), in particular treprostinil sodium.

[0073] The present invention utilizes a soft mist inhaler for administering Treprostinil or its pharma- ceutically acceptable salt or derivative, or in other words, a soft mist inhalation device.Suitable softest inhalers are known to those skilled in the art and are described, for example, in US 2014 / 076308 or WO 2018 / 197730.Several different types of soft mist inhalers based on different nebulization methods are available.Some soft mist inhalers are based on a vibrating membrane, such as the Philips InnoSpire, while other soft mist inhalers utilize pressurized liquid and / or propellant to aerosolize the composition.

[0074] In the context of the present invention, the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof, in certain embodiments, have a mass media aerodynamic diameter (MMAD) of about 1 μm to about 10 μm, or about 2 μm to about 8 μm, or about 4 μm to about 6 μm, when aerosolized using a soft mist inhaler.

[0075] In particular, the present invention relates to a method or medicament for use in a method as defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension as defined above, wherein the soft mist inhaler is adapted to generate an aerosol or plume of aerosols of the first, second and optional third liquid compositions having an average velocity of 1.0 to 2.5 m / s, preferably 1.3 to 2.1 m / s.

[0076] In a preferred embodiment, the present invention relates to a method or medicament for use in the method defined above, or to Treprostinil or its pharmaceutically acceptable salt or derivative for use in the method for treating and preventing pulmonary hypertension defined above, wherein the soft mist inhaler is adapted to hold the first, second and optional third liquid compositions comprising Treprostinil or its pharmaceutically acceptable salt or derivative at atmospheric pressure (non-pressurized form).Preferably, the soft mist inhaler also does not utilize a propellant gas (such as a hydrofluoroalkane (HFA), e.g. HFA-134a or HFA-227) to aerosolize or nebulize each liquid composition.

[0077] Preferred inhalers for use in the context of the present invention are purely mechanical and manual soft mist inhalers that do not utilize electrical means to atomize the composition.

[0078] Thus, in some preferred embodiments the present invention relates to a method or a medicament for use in the methods defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension defined above, wherein the soft mist inhaler is adapted to aerosolize the first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof by an entirely mechanical mechanism, preferably a mechanism that does not comprise electronic means.

[0079] Mechanical soft mist inhalers that do not rely on pressurized aerosols or electrical means to spray the composition often use special nozzles to spray the liquid composition, including but not limited to nozzles based on the Lowry principle, or swirl nozzles or impingement type nozzles.

[0080] In a preferred embodiment, the present invention relates to a method or a medicament for use in the method defined above, or to Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating or preventing pulmonary hypertension defined above, wherein the soft mist inhaler is equipped with a nozzle for aerosolization of a first, second and optionally third liquid composition comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof.

[0081] In a particularly preferred embodiment, the soft mist inhaler comprises a pumping unit adapted to generate an operating pressure of the first, second and optional third liquid composition comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the range of about 50 to about 350 bar, or in the range of about 50 to about 250 bar or about 100 to about 250 bar. Preferably, the pumping unit is mechanical and manually operated by the user.

[0082] In a particular embodiment of the present invention, the soft mist inhaler is an impingement type soft mist inhaler having at least one nozzle with at least two ejection channels adapted to generate at least two jets of the first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof that intersect to generate an aerosol. In a further particular embodiment, the at least two ejection channels are adapted or oriented such that at least two liquid jets ejected therefrom collide to generate an aerosol of each liquid composition. In a further particular embodiment, the impingement type soft mist inhaler has two ejection channels. In yet a further embodiment, the ejection channels have a diameter in the range of about 4 μm to about 15 μm, or about 6 μm to about 12 μm, or about 8 μm to about 10 μm.

[0083] In a preferred embodiment of the invention, the soft mist inhaler is a handheld inhalation device, i.e. a device that can be held and operated in one or both hands of a user to deliver nebulized medically active aerosol for inhalation therapy, (a) a housing having a user-facing side; (b) an impingement nozzle for generating an atomized aerosol by the impact of at least two liquid jets, the impingement nozzle being fixedly attached to a user-facing side of the housing so as to be immovable relative to the housing; and (c) a fluid reservoir disposed within the housing; (d) a pumping unit disposed within the housing, the pumping unit comprising: an upstream end fluidly connected to a fluid reservoir; a downstream end fluidly connected to the nozzle; the pumping unit is adapted to pump fluid from the fluid reservoir to the nozzle; The pumping unit is (i) a riser pipe having an upstream end, - adapted to act as a piston in a pumping unit, a riser pipe fixedly attached to the user-facing side of the housing so as to be immovable relative to the housing; (ii) a hollow cylinder located upstream of the riser pipe, the upstream end of the riser pipe being inserted into the cylinder such that the cylinder is longitudinally movable on the riser pipe; (iii) lockable means for storing potential energy when locked and releasing the stored energy when unlocked, the lockable means being disposed outside of and mechanically coupled to the cylinder such that unlocking of the means results in longitudinal propulsive movement of the cylinder towards the downstream end of the pumping unit.

[0084] Such inhalation devices are described, for example, in WO 2018 / 197730, the contents of which are incorporated herein by reference in their entirety. An advantage of such soft mist inhalation devices operating on a purely mechanical pressure source is that, for example, such soft mist inhalation devices allow aerosolization of a wide variety of liquid compositions having different liquid vehicles and concentrations of dissolved active substances, such as treprostinil or a pharma- ceutically acceptable salt or derivative thereof, resulting in a wide variation in physical properties associated with aerosolization, such as density, viscosity, vapor pressure and / or surface tension, especially when aerosolized with an impingement nozzle.

[0085] In a fifth aspect, the present invention further relates to a kit comprising a soft mist inhaler and said first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof. The kit preferably further comprises instructions for carrying out said method, in particular instructions for administering the liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof. It is noted that all embodiments or features disclosed in relation to a method or a medicament for use in the method defined above or a treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in the method for treating or preventing pulmonary hypertension according to the first to fourth aspects of the invention defined above apply equally to the kit of this fifth aspect of the invention.

[0086] Thus, the present invention further comprises: a) a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; b) a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, and, optionally, c) a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, The second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is higher than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition, and the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the optional third liquid composition is higher than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition.

[0087] The first, second and third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof are as defined above for the methods or medicaments according to the first to fourth aspects of the invention.

[0088] Thus, the first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition of the kit is selected in some embodiments within the range of about 1 mg / mL to about 5 mg / mL or about 3 mg / mL. In some embodiments, the first concentration is selected in the range of about 0.8 mg / mL to about 2 mg / mL or about 1 mg / mL to about 2 mg / mL. In certain embodiments, the first concentration is selected in the range of about 1.2 mg / mL to about 1.9 mg / mL or about 1.4 mg / mL to about 1.8 mg / mL, preferably about 1.5 mg / mL to about 1.7 mg / mL, for example, about 1.6 mg / mL. In some embodiments, the first concentration is in the range of about 1 mg / mL to about 2 mg / mL. In certain embodiments, the first concentration is in the range of about 1.4 mg / mL to about 1.8 mg / mL, preferably 1.5 mg / mL to about 1.7 mg / mL.

[0089] The second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is selected in some embodiments within the range of about 1.6 mg / L to about 6 mg / mL or about 2 mg / mL to about 6 mg / mL. Preferably, as outlined above, the concentration of treprostinil in the second liquid composition is about twice that of the first liquid composition. In some embodiments, the concentration of the second liquid composition is selected within the range of about 1.6 mg / mL or about 1.8 mg / mL or about 2 mg / mL to about 3.8 mg / mL or about 4 mg / mL. In certain embodiments, the concentration is within the range of about 2.8 mg / mL to about 3.6 mg / mL, preferably about 3 mg / mL to about 3.4 mg / mL, for example about 3.2 mg / mL.

[0090] The third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the optional third liquid composition is selected within the range of about 2.4 mg / mL to about 9 mg / mL or about 3 mg / mL to about 9 mg / mL. Preferably, as outlined above, the concentration of treprostinil in the optional third liquid composition is about three times that of the first liquid composition. In some embodiments, the concentration of the third liquid composition is selected within the range of about 2.4 mg / mL to about 6 mg / mL or about 2.6 mg / mL or about 2.8 mg / mL or about 3 mg / mL to about 6 mg / mL. In certain embodiments, the concentration of treprostinil in the optional third liquid composition is selected within the range of about 3.2 mg / mL to about 5.0 mg / mL, preferably about 4.2 mg / mL to about 5.0 mg / mL, for example 4.9 mg / mL.

[0091] In certain embodiments, the present invention relates to a kit as defined above, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1 mg / mL to about 3 mg / mL, in particular about 1.5 mg / mL to 1.7 mg / mL, as defined above, and the concentration of treprostinil in the second liquid composition is about twice that of treprostinil in the first liquid composition. In some embodiments, the kit comprises an optional third liquid composition as defined above, wherein the concentration of treprostinil in the third liquid composition is about three times that of treprostinil in the first liquid composition.

[0092] To improve treatment efficiency and ease of use, the liquid composition comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof is preferably provided in a separate container, or in a separate soft mist inhaler.

[0093] Thus, in some embodiments, the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof are provided separately in the first, second and optional third containers.

[0094] In a further embodiment, the kit comprises a first, second and optionally a third soft mist inhaler, each soft mist inhaler containing one of the first, second and optionally a third liquid compositions. The compositions are preferably provided in the form of cartridges for the soft mist inhalers, which may be provided separately or may be pre-inserted.

[0095] Thus, in some embodiments, the kit according to the invention comprises a single soft mist inhaler adapted to sequentially receive and aerosolize the first, second and optional third liquid compositions, wherein the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof are provided in separate containers, which are preferably cartridges for the soft mist inhaler.

[0096] In certain embodiments, the kit comprises: a) a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; b) a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, and, optionally, c) a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; d) a soft mist inhaler; The second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is higher than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition, and the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the optional third liquid composition is higher than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition, and each liquid composition is provided in a separate container.

[0097] In certain embodiments, the containers referred to herein for holding each of the first, second and optional third liquid compositions are dimensioned to contain each liquid composition in a quantity sufficient to dispense multiple doses of each liquid therefrom. In certain embodiments, the containers have an internal volume for holding about 2 mL to about 8 mL, or about 3 mL to about 6 mL, or about 4 mL to about 5 mL of each liquid composition. Thus, in further preferred embodiments, the containers referred to herein are adapted to hold at least about 1 to about 25, or about 3 to about 15, or about 5 to about 10 daily doses of the corresponding liquid composition.

[0098] In a further embodiment, the kit according to this aspect of the invention comprises a soft mist inhaler adapted to aerosolize the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof by an entirely mechanical mechanism, preferably a mechanism that does not comprise electronic means as described above.

[0099] In a preferred embodiment, the soft mist inhaler provided in the kit comprises a pumping unit adapted to generate an operating pressure of the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the range of about 50 to about 350 bar. Preferably, the pumping unit is mechanical and manually operated by a user.

[0100] In a further preferred embodiment of the kit, the soft mist inhaler is an impingement type soft mist inhaler, with at least one nozzle, with at least two ejection channels adapted to generate at least two jets of the first, second and optional third liquid composition comprising Treprostinil or its pharma- ceutically acceptable salt or derivative intersecting to generate aerosol.In a further preferred embodiment, the at least two ejection channels are adapted or oriented to generate at least two liquid jets ejected therefrom to collide to generate aerosol of each liquid composition.

[0101] In an even further preferred embodiment of the kit, the soft mist inhaler is a handheld inhalation device for delivering nebulized medically active aerosol for inhalation therapy, (a) a housing having a user-facing side; (b) an impingement nozzle for generating an atomized aerosol by the impact of at least two liquid jets, the impingement nozzle being fixedly attached to a user-facing side of the housing so as to be immovable relative to the housing; and (c) a fluid reservoir disposed within the housing; (d) a pumping unit disposed within the housing, the pumping unit comprising: an upstream end fluidly connected to a fluid reservoir; a downstream end fluidly connected to the nozzle; the pumping unit is adapted to pump fluid from the fluid reservoir to the nozzle; The pumping unit is (i) a riser pipe having an upstream end, - adapted to act as a piston in a pumping unit, a riser pipe fixedly attached to the user-facing side of the housing so as to be immovable relative to the housing; (ii) a hollow cylinder located upstream of the riser pipe, the upstream end of the riser pipe being inserted into the cylinder such that the cylinder is longitudinally movable on the riser pipe; (iii) lockable means for storing potential energy when locked and releasing the stored energy when unlocked, the lockable means being disposed outside of and mechanically coupled to the cylinder such that unlocking of the means results in longitudinal propulsive movement of the cylinder towards the downstream end of the pumping unit.

[0102] The invention further relates to the following numbered items:

[0103] 1. A method for inhalation administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof to a subject in need of such administration, the method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The method, wherein the first and second liquid compositions are aerosolized and administered using a soft mist inhaler.

[0104] 2. The method of item 1, wherein the subject has been diagnosed with or is threatened by developing pulmonary hypertension.

[0105] 3. A pharmaceutical comprising treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use in the treatment of pulmonary hypertension in a subject diagnosed with pulmonary hypertension, the treatment comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The method, wherein the first and second liquid compositions are aerosolized and administered using a soft mist inhaler.

[0106] 4.iii) administering a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form during a third treatment period after the second treatment period; a third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the third liquid composition that is greater than a second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition; 2. The method or medicament of item 1, wherein the third liquid composition is aerosolized and administered using a soft mist inhaler.

[0107] 5. The method or pharmaceutical product according to any one of items 1 to 4, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1 mg / mL to about 3 mg / mL.

[0108] 6. The method or pharmaceutical product according to any one of items 1 to 5, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the second liquid composition is selected within the range of about 2 mg / mL to about 4 mg / mL.

[0109] 7. The method or pharmaceutical product according to any one of items 1 to 6, wherein the concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the third liquid composition is selected within the range of about 3 mg / mL to about 6 mg / mL.

[0110] 8. The method or medicament according to any one of items 1 to 7, wherein the first, second and optional third liquid compositions are each an aqueous solution comprising an aqueous solvent or a mixture of solvents.

[0111] 9. The method or pharmaceutical product according to any one of items 1 to 8, wherein the first, second and optional third liquid compositions further comprise one or more pharma- ceutically acceptable excipients.

[0112] 10. The method or medicament according to any one of items 1 to 9, wherein the duration of the first treatment period is selected within the range of about 1 day to about 15 days.

[0113] 11. The method or medicament according to any one of items 1 to 10, wherein the duration of the second treatment period is selected within the range of about 1 day to about 15 days.

[0114] 12. The method or medicament according to any one of items 1 to 11, wherein the amount of Treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the first treatment period is selected in the range of about 10 μg to about 25 μg, preferably about 15 μg to about 20 μg.

[0115] 13. The method or medicament according to any one of items 1 to 12, wherein the amount of Treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the second treatment period is selected in the range of about 25 μg to about 50 μg, preferably about 30 μg to about 40 μg.

[0116] 14. The method or medicament according to any one of items 1 to 13, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the third treatment period is selected in the range of about 40 μg to about 70 μg, preferably about 45 μg to about 60 μg.

[0117] 15. The method or medicament according to any one of items 1 to 14, wherein the amount of treprostinil or a pharma- ceutically acceptable salt or derivative thereof administered in a single event during the first, second and optional third treatment periods is administered in one breath, respectively, upon a single actuation of a soft mist inhaler from which a single metered dose of treprostinil or a pharma- ceutically acceptable salt or derivative is dispensed.

[0118] 16. The method or medicament according to any one of items 1 to 15, wherein treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the first treatment period at a daily dose selected within the range of about 40 μg to about 100 μg.

[0119] 17. The method or medicament according to any one of items 1 to 16, wherein treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the second treatment period at a daily dose selected within the range of about 100 μg to about 200 μg.

[0120] 18. The method or medicament according to any one of items 1 to 17, wherein treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to the subject during the third treatment period at a daily dose selected within the range of about 160 μg to about 280 μg.

[0121] 19. The method or medicament according to any one of items 1 to 18, wherein the treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the first, second and optional third liquid composition is treprostinil sodium.

[0122] 20. The method or medicine according to any one of items 1 to 19, wherein the soft mist inhaler is adapted to generate an aerosol or aerosol plume of the first, second and optional third liquid compositions having an average velocity of 1.0 to 2.5 m / s, preferably 1.3 to 2.1 m / s.

[0123] 21. The method or medicament according to any one of items 1 to 20, wherein the soft mist inhaler is adapted to hold the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof at atmospheric pressure (non-pressurized form).

[0124] 22. The method or medicament according to any one of items 1 to 21, wherein the soft mist inhaler is adapted to aerosolize the first, second and optional third liquid composition comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof by an entirely mechanical mechanism, preferably by a mechanism not comprising electronic means.

[0125] 23. The method or medicament according to any one of items 1 to 22, wherein the soft mist inhaler is equipped with a nozzle for aerosolization of the first, second and optional third liquid composition comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof.

[0126] 24. The method or medicament according to item 23, wherein the soft mist inhaler comprises a pumping unit adapted to generate an operating pressure of the first, second and optional third liquid composition comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof in the range of about 50 to about 350 bar.

[0127] 25. The method or medicament according to any one of items 1 to 24, wherein the soft mist inhaler is an impingement type soft mist inhaler having at least one nozzle with at least two ejection channels adapted to generate at least two jets of the first, second and optional third liquid composition comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof that intersect to generate an aerosol.

[0128] 26. A soft mist inhaler is a handheld inhalation device for delivering nebulized medically active aerosols for inhalation therapy; (a) a housing having a user-facing side; (b) an impingement nozzle for generating an atomized aerosol by the impact of at least two liquid jets, the impingement nozzle being fixedly attached to a user-facing side of the housing so as to be immovable relative to the housing; and (c) a fluid reservoir disposed within the housing; (d) a pumping unit disposed within the housing, the pumping unit comprising: an upstream end fluidly connected to a fluid reservoir; a downstream end fluidly connected to the nozzle; the pumping unit is adapted to pump fluid from the fluid reservoir to the nozzle; The pumping unit is (i) a riser pipe having an upstream end, - adapted to act as a piston in a pumping unit, a riser pipe fixedly attached to the user-facing side of the housing so as to be immovable relative to the housing; (ii) a hollow cylinder located upstream of the riser pipe, the upstream end of the riser pipe being inserted into the cylinder such that the cylinder is longitudinally movable on the riser pipe; (iii) lockable means for storing potential energy when locked and releasing the stored energy when unlocked, the lockable means being disposed outside of and mechanically coupled to the cylinder such that unlocking of the means results in longitudinal propulsive movement of the cylinder towards the downstream end of the pumping unit.

[0129] 27. A method for treating pulmonary hypertension in a subject suffering from pulmonary hypertension, comprising a method for inhalation administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof according to item 1.

[0130] 28. The method or medicine according to any one of items 1 to 27, wherein the pulmonary hypertension is pulmonary arterial hypertension.

[0131] 29. The method or medicine according to item 28, wherein the pulmonary arterial hypertension is WHO group I or WHO group III pulmonary arterial hypertension.

[0132] 30. A kit comprising: a) a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; b) a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, and, optionally, c) a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof, The second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is higher than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition, and the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the optional third liquid composition is higher than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition.

[0133] 31. The kit according to item 30, wherein the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof are provided separately in the first, second and optional third containers.

[0134] 32. The kit of item 31, further comprising a first, second and optionally a third soft mist inhaler, each soft mist inhaler comprising one of the first, second and optionally a third cartridge.

[0135] 33. The kit of item 31, further comprising a single soft mist inhaler adapted to sequentially receive the first, second and optional third cartridges.

[0136] 34. The kit of any one of items 30 to 33, further comprising instructions for use of the first, second and optional third containers.

[0137] The following examples serve to illustrate the present invention, but said examples should not be understood as limiting the scope of the invention. EXAMPLES

[0138] Example 1

[0139] A liquid transparent aqueous solution of treprostinil sodium at a concentration of 1.0 mg / mL was prepared and loaded into an impingement type soft mist inhaler with two ejection channels of 8 μm diameter, a dose volume of 15 μL and an operating pressure of 250 bar, as further described in Example 5 below. The puffing experiment resulted in the formation of an aerosol plume with characteristics as summarized in Table 1, where "Event Duration" [s] means the time span required for the generation of the aerosol plume of a single actuation of the soft mist inhaler, "Dv10 / 50 / 90" [μm] means the volumetric parameters of the droplet size distribution, "V<10 / <5 μm" [%] means the volume of all droplets with a diameter less than 10 μm / 5 μm, "GSD" [μm] means the geometric standard deviation, and "St dev " means standard deviation, "N" means number of experiments, and "St error " means standard error, "CI" means confidence interval, and "RSD" means relative standard deviation.

[0140] [Table 1]

[0141] The corresponding droplet size distribution of the generated aerosol was measured with a laser diffraction system (Spraytec instrument from Malvern) and is shown in Figure 1. As can be seen from the graph, the maximum of the droplet size distribution is less than 5 μm. More specifically, 83.6% of all droplets have a diameter less than 10 μm and 46.8% of all droplets have a diameter less than 5 μm. Example 2

[0142] In this example, the suitability for long-term performance of selected soft mist inhalers as described in Examples 1 and 5 to generate aerosols containing treprostinil sodium was investigated. The device was actuated 120 times in a series of 6 actuations, and the event duration (the time span required to generate the aerosol plume of a single actuation) and particle (droplet) size distribution were determined for each series of 6 actuations. The results are summarized in Table 2 and Figure 2 shown below.

[0143] [Table 2]

[0144] The results of this long-term study showed that event duration and particle size distribution remained stable after 120 actuations. Example 3

[0145] A liquid clear aqueous solution of free treprostinil at a concentration of 5.0 mg / mL was prepared and loaded into an impaction soft mist inhaler similar to that described in Example 1. The spray experiment resulted in the formation of an aerosol plume with characteristics summarized in Table 3.

[0146] [Table 3]

[0147] The corresponding droplet size distribution was measured with a laser diffraction system (Spraytec instrument from Malvern) and is shown in Figure 3. As can be seen from the graph, the maximum of the droplet size distribution is less than 5 μm. More specifically, 97% of all droplets have a diameter less than 10 μm and almost 55% of all droplets have a diameter less than 5 μm. Example 4

[0148] A liquid clear solution of free treprostinil at a concentration of 5.0 mg / mL in a solution containing 50% water and 50% ethanol (v / v) was prepared and loaded into an impaction type soft mist inhaler similar to that described in Example 1. The spraying experiment resulted in the formation of an aerosol plume having the characteristics summarized in Table 4 below.

[0149] [Table 4]

[0150] The corresponding droplet size distribution was measured with a laser diffraction system (Spraytec instrument from Malvern) and is shown in Figure 4. As can be seen, 74.1% of all droplets have a diameter less than 10 μm and 41.8% of all droplets have a diameter less than 5 μm. Example 5

[0151] 5 shows a cross-sectional view of a soft mist inhaler (10) suitable for implementation in methods, compositions for use, and kits according to the invention, comprising an inhalation device (20) and a replaceable reservoir in the form of a cartridge or container (30) that is inserted into the inhalation device. The inhalation device (20) has a housing (21) having a lower part (22), which can be removed from the inhalation device (20) to open the housing (21) and allow access to a receiving unit (23) into which the replaceable container (30) can be inserted. The receiving unit (23) further has a connection unit (24) adapted to releasably and fluidly connect to a connection port (32) of the replaceable container (30).

[0152] The inhalation device (20) further comprises a nozzle (25) located at the downstream end of the inhalation device for aerosolizing the first, second or third liquid composition, respectively, provided in the replaceable container (30). The inhalation device further comprises a pumping unit (40) disposed within the housing (21). The pumping unit is fluidly connected to the container (30) and the nozzle (25) (via the connection unit (24) of the receiving unit (23)) and is adapted to pump the first, second or third liquid composition, respectively, in a downstream direction from the container (30) to the nozzle (25).

[0153] The pumping unit (40) has an upstream end (41) fluidly connected to the replaceable container (30) and a downstream end (42) fluidly connected to the nozzle (25), and the pumping unit (40) further comprises: (i) a riser pipe (43) having an upstream end (44), the riser pipe (43) adapted to function as a piston within the pumping unit (40) and fixedly attached to the user-facing (downstream) side of the housing (21) such that the riser pipe (43) is immovable relative to the housing (21); and (ii) a hollow cylinder (45) located upstream of the riser pipe (43), the upstream end (44) of the riser pipe being inserted into the cylinder (45) such that the cylinder (45) is longitudinally movable on the riser pipe (43).

[0154] As also shown in FIG. 5, pumping unit (40) (iii) includes lockable means (46) for storing potential energy when locked and releasing the stored energy when unlocked, the means (46) being disposed outside of and mechanically coupled to cylinder (45) such that unlocking of the means (46) results in longitudinal propulsive movement of cylinder (45) towards the downstream end of pumping unit (42).

Claims

1. 1. A pharmaceutical product comprising treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use in the treatment of pulmonary hypertension in a subject diagnosed with pulmonary hypertension or for use in the prevention of pulmonary hypertension in a subject at risk of developing pulmonary hypertension, said treatment or prevention comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

2. 1. Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use in a method for treating pulmonary hypertension in a subject diagnosed with pulmonary hypertension or for use in a method for preventing pulmonary hypertension in a subject at risk of developing pulmonary hypertension, i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

3. The process comprising: iii) administering a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form during a third treatment period after the second treatment period; the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the third liquid composition is greater than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition; 3. The pharmaceutical for use according to claim 1, or treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to claim 2, wherein the third liquid composition is aerosolized and administered to the subject using a soft mist inhaler.

4. The pharmaceutical agent or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 3, wherein a concentration of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof in the first liquid composition is selected within the range of about 1 mg / mL to about 3 mg / mL.

5. The pharmaceutical agent or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 4, wherein the concentration of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof in the second liquid composition is selected within the range of about 2 mg / mL to about 4 mg / mL.

6. The pharmaceutical agent or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 5, wherein a concentration of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof in the third liquid composition is selected within the range of about 3 mg / mL to about 6 mg / mL.

7. 7. The pharmaceutical agent or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 6, wherein the first, second and optional third liquid compositions are each an aqueous solution comprising an aqueous solvent or a mixture of solvents.

8. The pharmaceutical agent or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 7, wherein the first, the second and the optional third liquid composition further comprise one or more pharma- ceutically acceptable excipients.

9. The medicament for use or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof according to any one of claims 1 to 8, wherein the duration of the first treatment period is selected within the range of about 1 day to about 15 days.

10. The medicament for use according to any one of claims 1 to 9, wherein the duration of the second treatment period is selected within the range of about 1 day to about 15 days.

11. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 10, wherein the amount of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof administered in a single event during said first treatment period is selected in the range of about 10 μg to about 25 μg, preferably about 15 μg to about 20 μg.

12. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 11, wherein the amount of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof administered in a single event during said second treatment period is selected in the range of about 25 μg to about 50 μg, preferably about 30 μg to about 40 μg.

13. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 12, wherein the amount of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof administered in a single event during said third treatment period is selected in the range of about 40 μg to about 70 μg, preferably about 45 μg to about 60 μg.

14. 14. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 13, wherein the amount of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof administered in a single event during the first, second and optional third treatment periods is administered in one breath, respectively, upon a single actuation of the soft mist inhaler which dispenses a single metered dose of Treprostinil or a pharma- ceutical acceptable salt or derivative thereof.

15. The pharmaceutical product or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 14, wherein Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to said subject during said first treatment period at a daily dose selected within the range of about 40 μg to about 100 μg.

16. The pharmaceutical product or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 15, wherein Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to said subject during said second treatment period at a daily dose selected within the range of about 100 μg to about 200 μg.

17. The pharmaceutical product or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 16, wherein Treprostinil or a pharma- ceutically acceptable salt or derivative thereof is administered to said subject during said third treatment period at a daily dose selected within the range of about 160 μg to about 280 μg.

18. 18. The pharmaceutical product or treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 17, wherein the treprostinil or a pharma- ceutically acceptable salt or derivative thereof in said first, said second and said optional third liquid composition is treprostinil sodium.

19. 19. The medicament or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 18, wherein said soft mist inhaler is adapted to generate an aerosol or plume of aerosol of said first, second and optional third liquid compositions having an average velocity of 1.0 to 2.5 m / s, preferably 1.3 to 2.1 m / s.

20. 20. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 19, wherein said soft mist inhaler is adapted to hold said first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutical acceptable salt or derivative thereof at atmospheric pressure.

21. 21. The pharmaceutical product or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 20, wherein said soft mist inhaler is adapted to aerosolize said first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof by an entirely mechanical mechanism, preferably by a mechanism that does not comprise electronic means.

22. 22. The pharmaceutical agent or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 21, wherein said soft mist inhaler is equipped with a nozzle for aerosolization of said first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutical acceptable salt or derivative thereof.

23. 23. The pharmaceutical product or Treprostinil or a pharma- ceutical acceptable salt or derivative thereof for use according to any one of claims 1 to 22, wherein said soft mist inhaler comprises a pumping unit adapted to generate an operating pressure of said first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutical acceptable salt or derivative thereof in the range of about 50 to about 350 bar.

24. 24. The pharmaceutical product or Treprostinil or a pharma- ceutically acceptable salt or derivative thereof for use according to any one of claims 1 to 23, wherein said soft mist inhaler is an impingement type soft mist inhaler having at least one nozzle with at least two ejection channels adapted to generate at least two jets of said first, second and optional third liquid compositions comprising Treprostinil or a pharma- ceutically acceptable salt or derivative thereof that intersect to generate an aerosol.

25. said soft mist inhaler being a handheld inhalation device for delivering nebulized medically active aerosols for inhalation therapy; (a) a housing having a user-facing side; (b) an impingement nozzle for generating the atomized aerosol by the impact of at least two liquid jets, the impingement nozzle being fixedly attached to the user-facing side of the housing so as to be immovable relative to the housing; and (c) a fluid reservoir disposed within the housing; (d) a pumping unit disposed within the housing, the pumping unit comprising: an upstream end fluidly connected to said fluid reservoir; a downstream end fluidly connected to said nozzle, the pumping unit is adapted to pump fluid from the fluid reservoir to the nozzle; The pumping unit comprises: (i) a riser pipe having an upstream end, - adapted to act as a piston within said pumping unit, a riser pipe rigidly attached to the user-facing side of the housing so as to be immovable relative to the housing; (ii) a hollow cylinder located upstream of the riser pipe, the upstream end of the riser pipe being inserted into the cylinder such that the cylinder is longitudinally movable on the riser pipe; (iii) lockable means for storing potential energy when locked and releasing the stored energy when unlocked, the lockable means being disposed outside of and mechanically coupled to the cylinder such that unlocking of the means results in longitudinal propulsive movement of the cylinder towards the downstream end of the pumping unit.

26. 1. A method for inhalation administration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof to a subject in need of such administration, said method comprising: i) administering to the subject a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a first treatment period; ii) administering to the subject a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof in aerosolized form for a second treatment period following the first treatment period; the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition; The method, wherein the first and second liquid compositions are aerosolized and administered to the subject using a soft mist inhaler.

27. 27. The method of claim 26, wherein the subject has been diagnosed with or is at risk for developing pulmonary hypertension.

28. 28. A method for treating pulmonary hypertension in a subject suffering from pulmonary hypertension or for preventing pulmonary hypertension in a subject at risk of developing pulmonary hypertension, comprising a method for administering by inhalation treprostinil or a pharma- ceutical acceptable salt or derivative thereof according to claim 26 or 27.

29. 29. The method or medicament of any one of claims 1 to 28, wherein the pulmonary hypertension is pulmonary arterial hypertension.

30. 30. The method or medicament of claim 29, wherein the pulmonary arterial hypertension is WHO Group I or WHO Group III pulmonary arterial hypertension.

31. A kit comprising: a) a first liquid composition comprising a first concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; b) a second liquid composition comprising a second concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; and, optionally, c) a third liquid composition comprising a third concentration of treprostinil or a pharma- ceutically acceptable salt or derivative thereof; wherein the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition is greater than the first concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the first liquid composition, and the third concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the optional third liquid composition is greater than the second concentration of treprostinil, or a pharma- ceutically acceptable salt or derivative thereof, in the second liquid composition.

32. 32. The kit of claim 31 , wherein the first, second and optional third liquid compositions comprising treprostinil or a pharma- ceutically acceptable salt or derivative thereof are provided separately in first, second and optional third containers.

33. 33. The kit of claim 31 or 32, further comprising a first, second and optionally a third soft mist inhaler, each soft mist inhaler comprising one of the first, second and optionally third liquid compositions.

34. 33. The kit of claim 32, further comprising a single soft mist inhaler adapted to receive the first, second and optional third containers in series.

35. 35. The kit of any one of claims 31 to 34, further comprising instructions for use of the first, second and optional third containers.

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