ABSTRACT The big profits and influence of pharmaceutical firms that again rose to prominence during the COVID pandemic illustrate far more than just the global reach and market power of Big Pharma. Here we instead explain the power of these firms as a consequence of structural cartelisation that is networked and nested across hybrid state and market relations. Global inequalities in access to COVID vaccines exposed the inequity outcomes of the cartelisation of the pharmaceutical sector in dramatic new ways. To come to critical terms with this cartelisation, we describe how it is comprised of three kinds of nested and networked layers of structural collusion: namely, (i) firm-firm collusion, (ii) firm-state collusion; and (iii) firm-state-philanthropy collusion. By suggesting that these kinds of collusional relations are nested, overlapping and deeply networked, we explain how they have come to work together structurally. And, in doing so, we argue, they serve to capture value from biomedical innovation in ways that limit global access to medicines while simultaneously entrenching the dominance of high-income countries, lead firms and the interests of investors.