ABSTRACT
In personalized medicine, a companion or complementary diagnostic (CDx) is a diagnostic product that is used to stratify patients for a treatment. Codeveloped diagnostics are used in all phases of drug development, moving from exploratory biomarker assays to pharmacodiagnostic development. Due to stringent regulatory and economic regulations, few have been approved by the FDA. Early investment from diagnostic companies carries high risk, given drug development lead times and regulatory approval. In addition, it may be difficult for pharmaceutical and diagnostic companies to agree on a revenue-sharing model. Regulatory approval of a CDx can be an extensive process and is not a guarantee of its use to predict patient response to a specified drug because regulators may allow for “lab-developed tests” to enter the commercial market post-approval. Additional considerations for both the pharmaceutical and diagnostic company include the market size eligible for the CDx, clinical trial study design, choice of biomarker platform (first-tier or second-tier in vitro diagnostic), manufacturer and market distribution models, strategies to achieve test adoption, and education and awareness of the CDx. Successful CDx pre-launch and post-launch planning, development, and testing require the pharmaceutical and diagnostic company to work collaboratively and align strategically to achieve common goals.
