Formulations, methods, kits, and dosage forms for treating atopic dermatitis and for improved stability of an active pharmaceutical ingredient

1. A pharmaceutical formulation comprising granules, wherein the granules comprise:

(i) a micronized compound that is 2-(1-(4-((4-(4-hydroxypiperidin -1-yl)phenyl)amino)-5-oxo-5,6-dihydropyrimido[4,5-d]pyridazin-2-yl)piperidin-4-yl)acetonitrile in an amount that is about 20 mg to 80 mg, or a pharmaceutically acceptable salt thereof;

(ii) hydroxypropyl cellulose; and

about 1 mg to 20 mg croscarmellose sodium;

wherein the formulation further comprises one or more extragranular components; and wherein the one or more extragranular components comprise sodium lauryl sulfate.

2. The pharmaceutical formulation of claim 1 , further comprising one or more antioxidants.

3. The pharmaceutical formulation of claim 2 , wherein the one or more antioxidants comprise at least one of vitamin E or butylated hydroxytoluene.

4. The pharmaceutical formulation of claim 3 , wherein the one or more antioxidants is vitamin E.

5. The pharmaceutical formulation of claim 1 , further comprising one or more fillers.

6. The pharmaceutical formulation of claim 5 , wherein the one or more fillers comprises lactose monohydrate.

7. The pharmaceutical formulation of claim 1 , wherein the extragranular components comprise at least one of: (a) one or more tableting fillers; (b) one or more disintegrants; (c) one or more lubricants; or (d) one or more surfactants.

8. The pharmaceutical formulation of claim 1 , wherein the extragranular components comprise at least one of: (a) one or more tableting fillers comprising microcrystalline cellulose; (b) one or more disintegrants comprising croscarmellose sodium; (c) or one or more lubricants comprising magnesium stearate.

9. The pharmaceutical formulation of claim 1 , wherein the compound is 2-(1-(4-((4-(4-hydroxypiperidin-1-yl)phenyl)amino) -5-oxo-5, 6-dihydropyrimido[4,5-d]pyridazin-2-yl)piperidin-4-yl)acetonitrile hydrochloride.

10. The pharmaceutical formulation of claim 1 , wherein the pharmaceutical formulation comprises about 20 mg, about 40 mg, or about 80 mg of the compound, calculated as a free base.

11. The pharmaceutical formulation of claim 10 , wherein the pharmaceutical formulation comprises about 40 mg of the compound, calculated as a free base.

12. The pharmaceutical formulation of claim 10 , wherein the pharmaceutical formulation comprises about 80 mg of the compound, calculated as a free base.

13. The pharmaceutical formulation of claim 1 , wherein the granules have a particle size of less than about 20 microns.

14. The pharmaceutical formulation of claim 1 , wherein the pharmaceutical formulation is a tablet.

15. The pharmaceutical formulation of claim 14 , wherein the tablet is coated.

16. The pharmaceutical formulation of claim 1 , comprising granules, wherein the granules comprise:

(i) a micronized compound that is 2-(1-(4-((4-(4-hydroxypiperidin-1-yl)phenyl)amino) -5-oxo-5,6-dihydropyrimido[4,5-d]pyridazin-2-yl)piperidin-4-yl)acetonitrile in an amount that is about 20 mg to 80 mg, or a pharmaceutically acceptable salt thereof;

(ii) hydroxypropyl cellulose;

(iii) about 1 mg to 20 mg croscarmellose sodium;

(iv) vitamin E; and

(v) lactose monohydrate.

17. The pharmaceutical formulation of claim 16 , wherein the compound is 2-(1-(4-((4-(4-hydroxypiperidin-1-yl)phenyl)amino) -5-oxo-5,6-dihydropyrimido[4,5-d]pyridazin-2-yl)piperidin-4-yl)acetonitrile hydrochloride.

18. The pharmaceutical formulation of claim 16 , wherein the pharmaceutical formulation comprises about 20 mg, about 40 mg, or about 80 mg of the compound, calculated as a free base.

19. The pharmaceutical formulation of claim 18 , wherein the pharmaceutical formulation comprises about 40 mg of the compound, calculated as a free base.

20. The pharmaceutical formulation of claim 18 , wherein the pharmaceutical formulation comprises about 80 mg of the compound, calculated as a free base.

21. The pharmaceutical formulation of claim 16 , wherein the extragranular components comprise microcrystalline cellulose, croscarmellose sodium, and magnesium stearate.

22. A kit comprising:

one or more dosage forms comprising the pharmaceutical formulation of claim 1 ; and

instructions for administering the one or more dosage forms to a subject suffering from an inflammatory disorder.

23. A method of treating an inflammatory disorder or autoimmune disease, comprising administering to a subject in need thereof the pharmaceutical formulation of claim 1 .

24. The method of claim 23 , wherein the inflammatory disorder or autoimmune disease is selected from atopic dermatitis, alopecia areata, hand and foot eczema, hidradenitis suppurativa, pemphigus vulgaris, psoriasis, cutaneous lupus, vitiligo, inflammatory bowel disease, rheumatoid arthritis, asthma, allergic rhinitis, systemic lupus erythematosus, psoriatic arthritis, and multiple sclerosis.

25. The method of claim 23 , wherein the inflammatory disorder is hand and foot eczema.

26. A method of preparing a tablet formulation, the method comprising:

(A) providing intragranular ingredients comprising

(i) a micronized compound that is 2-(1-(4-((4-(4-hydroxypiperidin -1-yl)phenyl)amino)-5-oxo-5,6-dihydropyrimido[4,5-d]pyridazin-2-yl)piperidin-4-yl)acetonitrile, or a pharmaceutically acceptable salt thereof; and

(ii) croscarmellose sodium;

(B) granulating the intragranular ingredients while adding a 10% w/w solution of one or more binders comprising hydroxypropyl cellulose in 99% v/v isopropyl alcohol until granules are formed;

(C) drying and milling the granules to make micronized granules;

(D) mixing the micronized granules with one or more extragranular components; and

(E) compressing the micronized granules and the one or more extragranular components into a tablet, thereby providing the tablet formulation;

wherein the one or more extragranular components comprise sodium lauryl sulfate.