API有细胞毒性，请问是不是不需要对毒性杂质进行研究了?

建议学习下ICH M7指导原则,对于晚期癌症用药，和API本身就是基毒的药物，是不需要研究其基因毒性杂质的。
"This guideline does not apply to drug substances and drug products intended for advanced cancer indications as defined in the scope of ICH S9. (4) Additionally, there may be some cases where a drug substance intended for other indications is itself genotoxic at therapeutic concentrations and may be expected to be associated with an increased cancer risk. Exposure to a mutagenic impurity in these cases would not significantly add to the cancer risk of the drug substance and impurities could be controlled at acceptable levels for non-mutagenic impurities."

概念混淆了吧，API是否是细胞毒，与要不要进行杂质研究没有必然联系，是杂质就要研究，毒性杂质更要研究。