ADA and glycogen storage disease VI: Similarly, in a second study of 237 patients who were receiving ADA [21], median CL was higher in patients with persistent active endoscopic disease compared to those who had achieved endoscopic remission (0.326 L/day vs. 0.247 L/day, respectively) with no significant difference seen in ADA concentration (median 11.7 μg/mL vs. 9.3 μg/mL, respectively).