Operationalizing Precision Medicine in Drug Development: Predictive Biomarkers, Companion Diagnostics, and Regulatory Pathways.

In South Korea, the spread of narcotics has been accelerating. In particular, the proportion of overdose cases among individuals in their 20s has increased markedly over the past several years, accounting for more than 30% of all identified cases and representing the largest affected age group. Among young adults with mental health problems, a concerning cycle has emerged in which individuals seek psychotropic substances and subsequently engage in repeated misuse. As a result, many addiction specialists have emphasized the urgent need for comprehensive measures to promote treatment engagement and prevent relapse, including policy initiatives, expansion of treatment services, and the development of recovery and rehabilitation programs []. Despite the increasing prevalence of substance use disorder (SUD), treatment infrastructure in South Korea remains limited. Only a small number of hospitals provide specialized inpatient treatment for individuals with SUD, and access to intensive treatment programs is restricted in many regions []. In the Seoul metropolitan area, where a large proportion of drug-related crime occurs, the availability of treatment facilities remains insufficient to meet the growing demand. Furthermore, community-based addiction services remain underdeveloped, limiting opportunities for continuous treatment and long-term recovery support []. Social stigma associated with drug use also creates additional barriers to care, discouraging individuals from seeking treatment and contributing to delayed intervention []. The challenges surrounding addiction treatment are not unique to South Korea. There is international evidence suggesting that a large proportion of individuals with SUD do not receive adequate treatment. For example, national survey data from the United States indicate that many individuals with SUD do not access treatment services due to structural barriers such as limited treatment availability, financial constraints, or lack of motivation for treatment engagement []. In addition, structural inequalities in health care systems may further restrict access to addiction treatment and medication-assisted therapy in socially disadvantaged communities [].