This trial is conducted in Europe and North America. The aim of the trial is to assess disease activity and safety in subjects with moderately to severely active Crohn's disease (CD) when treated with NNC 0142-0000-0002.

Inclusion Criteria:

• Subjects with CD for at least 3 months
• Subjects not treated before, or subjects who have either not responded to treatment, or responded and then lost the response during continued administration of a therapeutic compound

Exclusion Criteria:

• Any of the following: Symptomatic bowel obstruction, short bowel syndrome, ileostomy or colostomy, surgical bowel resection within 6 months prior to randomisation or clinically relevant un-drained abscess
• History of dysplasia or malignancy in the colon
• Any ongoing chronic or active infectious disease or microbial infection requiring systemic oral or intravenous treatment against infection within 1 month prior to randomisation
• Body mass index (BMI) higher or equal to 38.0 kg/m^2