PHARMACEUTICAL COMPOSITIONS COMPRISING RPL554 IN HFA-134A FOR ADMINISTRATION BY INHALATION

1 . A method of treating or preventing a respiratory disorder in a subject, which method comprises administering to said subject an effective amount of a liquid pharmaceutical composition,

which liquid pharmaceutical composition is suitable for administration by inhalation and comprises:

(i) a suspension of particles comprising 9,10-dimethoxy-2-(2,4,6-trimethylphenylimino)-3-(N-carbamoyl-2-aminoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6,1-a]isoquinolin-4-one (RPL554); and

(ii) a diluent which is 1,1,1,2-tetrafluoroethane (HFA-134a),

wherein the liquid pharmaceutical composition contains less than 0.05% by weight of a surfactant relative to the total weight of the composition.

2 . A method according to claim 1 , wherein the liquid pharmaceutical composition contains less than 0.05% by weight of any additional excipient selected from a co-solvent and a surfactant relative to the total weight of the composition.

3 . A method according to claim 1 , wherein the liquid pharmaceutical composition contains less than 0.05% by weight of any additional excipient relative to the total weight of the composition.

4 . A method according to claim 1 , wherein the liquid pharmaceutical composition contains less than 0.01% by weight of said surfactant or said additional excipient, relative to the total weight of the composition.

5 . A method according to claim 1 , wherein the particles comprise at least 50% by weight of RPL554 relative to the total weight of the particles.

6 . A method according to claim 1 , wherein RPL554 is the sole active agent in the liquid pharmaceutical composition.

7 . A method according to claim 1 , wherein the liquid pharmaceutical composition which consists essentially of (i) RPL554 and (ii) 1,1,1,2-tetrafluoroethane.

8 . A method according to claim 1 , wherein the liquid pharmaceutical composition comprises at least 99.5% by weight of (i) RPL554 and (ii) 1,1,1,2-tetrafluoroethane relative to the total weight of the composition.

9 . A method according to claim 1 , wherein the particles comprising RPL554 have a particle size distribution with a Dv50 (median particle size by volume) value of from about 0.2 μm to about 5 μm.

10 . A method according to claim 1 , wherein the concentration of particles comprising RPL554 in the liquid pharmaceutical composition is from about 0.1 mg/mL to about 200 mg/mL.

11 . A method according to claim 1 , wherein the liquid pharmaceutical composition is suitable for administration by pressurised metered dose inhaler.

12 . A method according to claim 1 , wherein the liquid pharmaceutical composition is administered by a pressurised metered dose inhaler.

13 . (canceled)

14 . A method according to claim 1 , wherein the respiratory disorder is selected from asthma, allergic asthma, hay fever, allergic rhinitis, bronchitis, emphysema, bronchiectasis, chronic obstructive pulmonary disease (COPD), adult respiratory distress syndrome (ARDS), steroid resistant asthma, severe asthma, paediatric asthma, cystic fibrosis, lung fibrosis, pulmonary fibrosis and interstitial lung disease.

15 . A method according claim 14 , wherein the respiratory disorder is chronic obstructive pulmonary disease (COPD).

16 . (canceled)

17 . A method according to claim 2 , wherein the liquid pharmaceutical composition contains less than 0.01% by weight of said additional excipient, relative to the total weight of the composition.

18 . A method according to claim 1 , wherein the liquid pharmaceutical composition contains less than 0.001% by weight of said surfactant, relative to the total weight of the composition.

19 . A method according to claim 2 , wherein the liquid pharmaceutical composition contains less than 0.001% by weight of said additional excipient, relative to the total weight of the composition.

20 . A method according to claim 1 , wherein the particles comprise at least 99% by weight of RPL554 relative to the total weight of the particles.