The carrier has denied coverage of Prometheus Anser IFX testing as investigational. There is a letter to Nancy Twigg from the carrier dated 11/24/15. In the letter, the carrier states in part: “The submitted medical records were reviewed. In accordance with the Medical Mutual Corporate Medical Policy 201303 for Genetic Testing and Genetic Counseling General Policy, it was determined that the Prometheus Anser IFX is investigational. This test has insufficient evidence for …show more content…
Second, if no inflammation is confirmed, then other disease processes should be excluded (e.g., C. deficile, steatorrhea, etc.). Then, as outlined in the position statement of the World Congress of Gastroenterology, an empiric increase in the TNF antagonistic dose (address low drug concentration); then switching the type of TNF antagonist (address antidrug antibodies) and finally changing class/mechanism of biologic or proceed to surgery (address non TNF mediated pathways).
This strategy has several inherent disadvantages. First, the patients who have developed high titers of anti-drug antibodies will be unlikely to respond to dose intensification at great cost and possible risk of allergic hypersensitivity reactions. Second the group with non-immune pharmacokinetic mechanisms may be over or under treated. Current data support the routine monitoring of trough levels of anti TNF drug concentration and anti-drug antibody concentration assessment into clinical practice to permit providers to optimize patient treatment by maintaining therapeutic drug concentrations over …show more content…
Indeed, experts have noted that adjusting drug doses based on clinical symptoms is often inaccurate. Furthermore, multiple factors in addition to anti-drug antibodies may influence pharmacokinetics (e.g., gender, body size, disease severity, TNF burden, and serum albumin). Finally, maintenance of an optimal drug level is associated with improved clinical outcomes, suggesting a role for therapeutic drug monitoring in routine clinical practice. After dose optimization they demonstrated that continued concentration-based dosing of infliximab was superior to clinically based dosing for achieving remission after 1 year and was associated with fewer disease flares during the course of