University of York - Centre for Health Economics, Imperial College London - Department of Infectious Disease Epidemiology, Government of Malawi - Department of Pharmaceuticals, Government of Malawi - Department of Pharmaceuticals, University College London - Institute for Global Health, University College London - Institute for Global Health, University College London - UCL Centre for Advanced Research, Imperial College London, University College London, University of Malawi - College of Medicine, Imperial College London, University College London, University College London, University College London, Ministry of Health and Population, Lilongwe - Department of Planning and Policy Development, Kamuzu University of Health Sciences - School of Global and Public Health (SOGAPH), Kamuzu University of Health Sciences - Health Economics and Policy Unit, University of Bergen, University of York, University College London - Institute for Global Health and Imperial College London - MRC Centre for Global Infectious Disease Analysis