Institutional tensions in HIV treatment: challenges in providing free antiretroviral drugs under China's 'Four Frees and One Care' policy.

China's 'Four Frees and One Care' policy provides people living with HIV (PLHIV) with free antiretroviral drugs (ARVs), while the recent inclusion of new ARVs in medical insurance policy has created policy overlap. Guided by the Institutional Analysis and Development (IAD) framework, this qualitative study used semi-structured interviews with 42 Centers for Disease Control and Prevention (CDC) and medical staff across China to examine institutional interactions and tensions in implementing the 'Four Frees and One Care' policy under policy overlap. The findings indicate that CDC and medical institutions exhibit divergent perceptions regarding the scope of beneficiaries for free ARVs, the allocation of responsibilities during implementation, and preferences in ARVs recommendations. CDC staff place greater emphasis on expanding antiretroviral therapy (ART) coverage to achieve public health goals for HIV control at the population level, whereas medical institutions focus more on individual treatment outcomes and the healthcare service performance. This divergence results in CDC favouring the free ARVs policy in practice, while medical institutions are more inclined toward ARVs accessed through medical insurance. Such tensions not only affect the coordination of policy implementation but may also have potential adverse impacts on PLHIV access to ART services, ART adherence, and public health outcomes.