西替利司他(Cetilistat/ATL-962)是一种治疗肥胖的药物或食品化合物之类。它的作用机制如同已上市的药物奥利司他(赛尼可/罗氏鲜/让你酷)是通过抑制"胰脂肪酶"(Pancreatic lipase)来达成，而胰脂肪酶是在肠脏(GI)中进行分解三酸甘油酯作用的酶。如果没有这种酶，在饮食中"三酸甘油酯"可以防止食物养份被水解为可吸收的游离脂肪酸、且使食物养份未被吸收的排泄掉。而「西替利司他」运作机制范围归属于「周围神经系统」

Cetilistat is a drug designed to treat obesity. It acts in the same way as the older drug orlistat (Xenical) by inhibiting pancreatic lipase, an enzyme that breaks down triglycerides in the intestine. Without this enzyme, triglycerides from the diet are prevented from being hydrolyzed into absorbable free fatty acids and are excreted undigested.