Dr. Mark Silverberg, Dr. David T Rubin, Dr. Laura Targownik, and Dr. Charabaty excitingly discuss why IBD specialists are divided on the topic of therapeutic drug monitoring (TDM). “If the drug is going to work but isn’t present in the body, it doesn’t do its job,” Dr. Rubin said. In addition, when a biologic medicine is present in low concentrations, some patients develop neutralizing antidrug antibodies that clear the substance from the body. “The idea is to monitor the amount of drug, so we can anticipate loss of response by keeping the drug in the body,” he said. Find out what other experts said here.