The subject invention provides a mixture of Crystalline Laquinimod sodium particles, wherein (i) ≧90% of the total amount by volume of the laquinimod sodium particles have a size of ≦40 μm or (ii) ≧50% of the total amount by volume of the laquinimod sodium particles have a size of ≦15 μm and wherein: a) the mixture has a bulk density of 0.2-0.4 g/mL; b) the mixture has a tapped density of 0.40-0.7 g/mL; c) an amount of heavy metal in the mixture is no more than 20 ppm relative to the amount by weight of laquinimod sodium; d) an amount of MCQ in the mixture is no more than 0.15% relative to the amount of laquinimod sodium as measured by HPLC; e) an amount of MCQCA in the mixture is no more than 0.15% relative to the amount of laquinimod sodium as measured by HPLC; or f) an amount of MCQME in the mixture is no more than 0.12% relative to the amount of laquinimod sodium as measured by HPLC. The subject invention also provides a pharmaceutical composition comprising an amount of laquinimod and at least one of BH-3-HKAQ, MCQ, MCQCA, MCQME, NEA, and MCQEE. The subject invention also provides processes for preparing BH-3-HLAQ, MCQ, MCQCA, MCQEE, and compounds prepared by said processes. Further provided is a process for testing whether a sample of laquinimod contains an undesirable impurity. Further provided is a process for preparing a validated pharmaceutical composition comprising laquinimod, for preparing a pharmaceutical composition comprising laquinimod, or for distributing a validated batch of a pharmaceutical composition comprising laquinimod, for validating a batch of a pharmaceutical product containing laquinimod and a pharmaceutically acceptable carrier for distribution, and for preparing a packaged pharmaceutical composition comprising laquinimod, each comprising determining the amount of at least one of BH-3-HLAO, MCQ, MCQCA, MCQME
本发明提供了一种晶体Laquinimod钠颗粒的混合物,其中(i)≧90%的Laquinimod钠颗粒的总体积具有≦40μm的尺寸或(ii)≧50%的Laquinimod钠颗粒的总体积具有≦15μm的尺寸,其中:a)混合物的堆积密度为0.2-0.4 g/mL;b)混合物的振实密度为0.40-0.7 g/mL;c)混合物中重金属的量相对于Laquinimod钠的重量不超过20 ppm;d)混合物中MCQ的量相对于用HPLC测量的Laquinimod钠的量不超过0.15%;e)混合物中MCQCA的量相对于用HPLC测量的Laquinimod钠的量不超过0.15%;或f)混合物中MCQME的量相对于用HPLC测量的Laquinimod钠的量不超过0.12%。本发明还提供了一种制药组合物,包括Laquinimod的量和至少一种BH-3-HKAQ、MCQ、MCQCA、MCQME、NEA和MCQEE。本发明还提供了制备BH-3-HLAQ、MCQ、MCQCA、MCQEE和通过该过程制备的化合物的过程。此外,本发明还提供了一种测试Laquinimod样品是否含有不良杂质的过程。本发明还提供了一种制备经过验证的Laquinimod制剂的过程,用于制备包含Laquinimod的制剂,或用于分发经过验证的包含Laquinimod的制剂批次,用于验证包含Laquinimod和药用载体进行分发的药物制品批次,并用于制备包装的包含Laquinimod的制剂,每个过程都包括确定样品或批次中至少一种BH-3-HLAO、MCQ、MCQCA、MCQME、NEA和MCQEE的量。本发明还提供了将BH-3-HLAQ、MCQ、MCQCA、MCQME、MCQEE用作参考标准,以检测含有Laquinimod的制剂中微量杂质的用途。最后,本发明提供了一种确定药物制剂中BH-3-HLAQ、MCQ、MCQCA、MCQME、MCQE<5-HLAQ、SPIRO-LAQ或H-LAQ浓度的方法。