Abstract: A pharmaceutically acceptable salt of a benzo[c]chroman compound and a polymorphic form and use of the pharmaceutically acceptable salt. The pharmaceutically acceptable salt is selected from hydrochloride, methanesulfonate, phosphate, L-tartrate, maleate, p-toluenesulfonate, sulfate, fumarate, succinate, citrate, malate, and hydrobromide. The pharmaceutically acceptable salt and the polymorphic form thereof improve the bioavailability and the stability, and as a cathepsin C inhibitor, can be used for treating asthma, obstructive pulmonary disease, bronchiectasis, ANCA-associated vasculitis, psoriasis, ?1-antitrypsin deficiency, lupus nephritis, diabetes, inflammatory bowel disease, rheumatoid arthritis, sinusitis, hidradenitis suppurativa, or cancer.

Abstract: Disclosed in the present invention are a polymorph of a benzo[c]chroman compound, a preparation method therefor and use thereof. The present invention particularly provides a polymorph of a compound represented by formula I, a preparation method therefor and use thereof. The compound represented by formula I is used as a cathepsin C inhibitor, and a crystalline form of the compound and a pharmaceutical composition comprising the crystalline form can be used for treating asthma, obstructive pulmonary diseases, bronchiectasis, ANCA-related vasculitis, psoriasis, ?1-antitrypsin deficiency, lupus nephritis, diabetes, inflammatory bowel diseases, rheumatic arthritis, rhinosinusitis, hidradenitis suppurativa or cancers.