Medicine, metaphors and metaphysics: An interdisciplinary analysis of the ethical, medical and sociocultural questions raised by therapeutic equivalence

The practice of medicine is the latter-day solution to that intensely human and social predicament we call illness. Medical discourse, however, increasingly tends towards guidelines, protocols, cost considerations and other institutionally-derived issues. This dissertation examines a single concept, therapeutic equivalence, and utilizes it as a metaphor for this focal shift, arguing that this reduced perspective not only ignores the considerable socio-cultural context in which illness takes place, but adversely affects the paradigms and practice of medicine - as well as research, policy and clinical care. Therapeutic equivalence is the basis for a health (pharmaceutical) policy usually called reference-based pricing, used in many jurisdictions and institutions around the world (such as New Zealand's Pharmac, the BC Reference Drug Program and the majority of American HMO's), in which pharmacoeconomic analyses determine the most costeffective drug(s) within a certain class of drugs in order to restrict general access. Using the well-studied BC reference drug program (RDP) as its primary example, this work examines the regulatory and evidentiary framework of the term 'equivalence', analyzes the medical research on therapeutic equivalence and delves into the deeper socio-cultural and epistemological questions the term raises to demonstrate how institutional and statistical interpretations of pathology now dominate medical discourse. The many uncertainties, ambiguities and variations inherent to physiology, pharmacodynamics and pharn~acokinetics are thus ignored; risk is minimized and subjective states and individual narratives of illness, largely disregarded. Moving from drug classificationsldefinitions and the conceptual underpinnings of medical research to the increased convergence of corporate and research interests, this work examines the limitations of ontological disease classifications which assume knowledge is static and questions the current emphasis on biomarkers and numeric results (e.g., blood pressure or cholesterol readings). This work argues that such classification systems are limiting and frame illness in reductionist ways - and have ethical, iatrogenic, medical, social and personal consequences. Broader and more nuanced communications, with greater patient input, are called for. Keywords: equivalence, therapeutic equivalence, reference based pricing, reference drug program, health economics, ethics of pharmaceutical policy, health policy criticism, epistemology of health, sociology of pharmaceutical policy, patient involvement, participatory action research and empowering patients