The present invention is directed to novel water-soluble pharmaceutically acceptable, crystalline addition salts of (i) an amine containing one or more hydroxyl and/or carboxylic groups with (ii) amino nicotinic acid derivatives of formula (I)wherein Ra, Rb, Rc and Rd independently represent groups selected from hydrogen atoms, halogen atoms, C1-4alkyl groups which may be optionally substituted by 1, 2 or 3 substituents selected from halogen atoms and hydroxy groups, and C1-4alkoxy groups which may be optionally substituted by 1, 2 or 3 substituents selected from halogen atoms and hydroxy groups, and pharmaceutically acceptable solvates thereof.本發明是針對(i)含有一或多個羥基及/或羧基之胺與(ii)式(I)之胺基菸鹼酸衍生物的新穎水溶性醫藥學上可接受之結晶加成鹽其中Ra、Rb、Rc以及Rd獨立地表示選自以下之基團：氫原子；鹵素原子；C1-4烷基，其可視情況經1、2或3個選自鹵素原子以及羥基之取代基取代；以及C1-4烷氧基，其可視情況經1、2或3個選自鹵素原子以及羥基之取代基取代；以及其醫藥學上可接受之溶劑合物。
