CPT® Code 80145

The CPT® Code 80145 refers to a laboratory test specifically designed to monitor therapeutic drug levels of adalimumab. Adalimumab is a fully human monoclonal antibody that targets and binds to tumor necrosis factor alpha (TNFa), a protein involved in the inflammatory response of the immune system. Elevated levels of TNFa are commonly associated with various inflammatory diseases, including uveitis, rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel diseases, and plaque psoriasis. Monitoring the levels of adalimumab is crucial, as therapeutic activity may be compromised in a significant percentage of patients. Approximately 10-30% of patients may experience inadequate dosing during the initial induction phase of treatment, leading to what is termed primary non-response. Additionally, around 50% of patients who initially respond to treatment may later show a lack of long-term clinical improvement, known as secondary non-response. These non-responses are often linked to low serum trough concentrations of adalimumab, which can be influenced by various factors such as high serum albumin levels, body weight, gender, smoking habits, disease severity, and the development of antibodies against TNFa. The rapid point-of-care test for adalimumab levels allows healthcare providers to assess serum drug trough concentrations immediately before the next scheduled dose, enabling timely dose adjustments without delaying the drug infusion schedule. The testing process involves obtaining a blood sample, which is then processed by diluting the serum with a buffering agent, mixing it, and loading it into a test cartridge. This cartridge is inserted into a preprogrammed reading device provided by the manufacturer and incubated for a duration of 15 minutes, after which the results are displayed on a digital screen.