Ustekinumab was started without a new chest X-ray or a repeat interferon gamma release assays test because the child was switched from another biologic.[40] Also, another case described drug-induced lung disease after starting Ustekinumab; the child complained of shortness of breath, chest pain, and cough.[41] Adult clinical trials are expanding the therapeutic options for IBD patients, but the time lag between adult and pediatric drug approval results in significant off-label use due to a lack of knowledge about optimal pediatric dosing regimens. This evidence concerns the gene IFNG and inflammatory bowel disease.