Trials of drugs to treat Crohn’s disease should add reduction of intestinal inflammation to their symptom-relief endpoints, according to an FDA draft guidance released Thursday in tandem with a draft guidance for conducting ulcerative colitis trials.

The 12-page guidance on Crohn’s disease drug trials recommends trials use an ileocolonoscopy to evaluate their drug’s effect on mucosal inflammatory changes in addition to the commonly used Crohn’s Disease Activity Index (CDAI), a weighted measurement that estimates disease severity but is ineffective in evaluating the intestinal inflammation that underlies Crohn’s disease.

The 15-page draft guidance on trials of ulcerative colitis drugs lays out recommendations for trial populations, designs, efficacy considerations and safety assessments, advising sponsors to use a design that can show a drug’s potential for long-term use.

Comments on both guidances are due to the FDA by June 24.

Read the Crohn’s disease draft guidance here: https://bit.ly/3MEoFGc.

Read the ulcerative colitis draft guidance here: https://bit.ly/3OK729F.