[Contribution of In- Vitro Diagnostics to Effective Use of Therapeutic Drugs -Perspectives from IVD Industry-].

The recent development of innovative therapeutic drugs has changed the relationship between diagnostics and therapeutic drugs. One of the major changes is personalized healthcare and companion diagnostics; many of innovative drugs such as Herceptin, Alectinib, and Atezolizumab have been developed and launched together with their corresponding companion diagnostics. Another aspect of the recent innovative drugs is the utilization of high-level biotechnology and develop- ment of antibody-based therapeutic drugs. Antibody-based drugs often induce heterophilic antibodies such as human anti-mouse antibody (HAMA). Taking this into account, the interference of HAMA is investigated intensively during the development of in-vitro diagnostics, and it is eliminated by employing countermeasures such as the addition of quench proteins, and utilization of fragmented antibodies as well as chimera-antibodies. With those measures, the incidence of interference can be reduced to acceptable levels and the assays can generate reliable results, which contribute to beneficial therapy. On the other hand, the recent development of innovative unique therapeutic drugs sometimes leads to interference in diagnostic assays, which were not expected during development. One example is interference observed in the BNP assay induced by a new drug for heart failure: angiotensin receptor-neprilysin inhibitor (ARNI). When patients take ARNI, BNP values increase instead of the improved condition of heart failure. Due to this observation, NT-proBNP, which is unaffected by ARNI, is usually used for monitoring the effect of the drug. The issue of drug-resistant bacteria is also discussed in conjunction with the potential contribution of diag- nostics for the effective use of antimicrobial agents. [Review].