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Artemisia Annua, Artemisinin, Acts and Malaria Control in Africa: the Interplay of Tradition, Science and Public Policy

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Artemisia Annua, Artemisinin, Acts and Malaria Control in Africa: the Interplay of Tradition, Science and Public Policy 1 Working Paper September 20, 2010 Artemisia annua, Artemisinin, ACTs and Malaria Control in Africa: The Interplay of Tradition, Science and Public Policy Dana G. Dalrymple 1 As to diseases, make a habit of two things –to help, or at least to do no harm. - Hippocrates, 460-377 BC2 The ends of this branch of knowledge [chemical philosophy] are the applications of natural substances to new uses, for increasing the comforts and enjoyments of man… - Sir Humphry Davy, 1812 It would be foolhardy of anyone to predict when and how malaria will be conquered. - Socrates Litsios, 1996 Abstract The key ingredient in the leading treatment for malaria in Africa - artemisinin - comes not from high- tech research, but is an extract of an ancient medicinal plant, Artemisia annua, commonly known as Artemisia. Chloroquine and replacement drugs have lost effectiveness with the development of resistance and have increasingly been replaced by derivatives of artemisinin combined with other drugs. Known as artemisinin–based combination therapies (ACTs), they provide the most effective treatment at present. This has led to efforts to increase cultivated production of Artemisia in the short run and to develop, through biological and chemical research, synthetic substitutes in the longer run. The resulting juxtaposition of activities and players provides both opportunities and challenges for society. While individual components have been examined, there is little in the way of comprehensive analysis. This paper attempts to weave the many complex and dynamic components - historical, scientific, technical, economic - together in order to aid understanding of the issues and facilitate development of informed public/private policies and actions. Although focused on Africa, the main components and issues are global in nature and resolution and relate to more general issues in infectious disease control and economic development. 1 The preparation of this paper through September 2008 was carried out while I served as Senior Research Advisor and Agricultural Economist, International Research and Biotechnology Team, Office of Environment and Science Policy, Bureau for Economic Growth, Agriculture and Trade, U.S. Agency for International Development, Washington, D. C. Following retirement, I have continued work on the paper as a personal effort and may be contacted at [email protected]. The views expressed are my own and not necessarily those of USAID. Mention of commercial firms and products does not imply endorsement. This is a revision and update of he December 10, 2009 version of the paper which was posted on the Medicines for Malaria Venture website [www.mmv.org/research-development/optimizing-artemisinin-production/related-publications]. 2 “Hippocrates was the first to clearly describe the different types of malaria depending on the periodicity of the fever – tertian and quarten fever patterns” (Cunha and Cunha 2008, p. 195). 2 Preface This account of a plant-based pharmaceutical drug and one of the world’s oldest and most important diseases had a somewhat unusual provenance. It grew out of a project supported by the U. S. Agency for International Development to provide technical support to farmers in East Africa in the production of Artemisia (Artemisia annua) for use in the manufacture of artemisinin-based combination drug therapies (ACTs). I participated in the evaluation of the proposal in mid to late 2004, as the agricultural member of an informal agency Artemisia Team. While we had good documentation at hand (TechnoServe 2004), it appeared to me that much more needed to be known before an adequate overall assessment could be made. Initially this led to extensive correspondence with specialists in the field and an extended review of literature, a process which continues. Along the way, I have encountered many highly knowledgeable specialists in various aspects of the subject, but few individuals with a broader interdisciplinary knowledge of the topic (principally historians). And while the volume of literature on malaria is massive, the distribution is definitely asymmetric. There is much more on (i) artemisinin and ACTs than Artemisia annua, and (ii) biological science than social science. Comprehensive policy analysis, with one notable exception (NA 2004), is scarcely in evidence and remains more of a goal than an achievement. The manuscript began as a modest briefing paper on Artemisia for the USAID Administrator in late 2004. It represents an ongoing attempt to bridge and balance several varied dimensions. As an agricultural economist with early training in plant science, my approach and emphases obviously may differ from those of formally trained malaria specialists, though I have drawn liberally from their work and advice over a number of years. The focus, as suggested in the title, is ultimately on public policy aspects and hence reflects and incorporates a number of additional dimensions of a historical, economic, and social nature. It also reflects a longstanding interest in science and technology policy and more recent attention to international health policy research and issues. The result is a broad, and hopefully fairly analytical, review that may be of background interest and value to both specialists and generalists. To facilitate this, the main text - which is fairly compressed and somewhat complex at points – is focused on broader topics and issues. Additional details, dimensions, and linkages are provided in 13 Annexes and 205 footnotes. There is also an extended and varied list of references (over 1,100). Thus readers can pick and choose; the paper may be read and used at several levels and in different ways. Useful collateral reading is provided in (1) three recent and excellent histories of malaria and malarial control efforts (Packard 2007, Webb 2009, Shah 2010), (2) the annual World Malaria Report (WHO 2008, 2009), and (3) annual reports of a U.K. Parliamentary Committee (APPMG 2010). An overview of technical and scientific aspects of malarial drugs is provided by Eastman and Fidock (2010), while a technical book on artemisinins by Lin and Weina is scheduled to be published in early 2011. Much has happened since the first version of this Working Paper was posted on the WHO/RBM website in July 2006. I have tried to incorporate the highlights, though some areas have been less well covered or remain elusive. This has involved, as before, a process of reading and consultation leading to corrections, clarifications, revision, and updating. It remains, as ultimately any study of such a complex and dynamic subject must be, incomplete, subject to error, and a continuing work in progress. Comments and corrections are welcome. 3 Contents I. Introduction (6-10) 1. The Importance of Malaria in Africa (6) 2. Evolution of Control Programs and Emphasis (7) a. Global Programs (7) b. Donor Emphasis (7) 3. Malaria and its Treatment (8) II. The Approach: Artemisinin-Based Combination Therapies (11-32) 1. Artemisia, Artemisinin and ACTs (11) a. Early Development of Artemisinin and Derivatives (11) b. Artemisinin-Based Combination Therapies (13) c. Subsequent Trials and Adoption of ACTs (15) 2. Artemisia: The Plant and Production (16) a. The Plant (16) b. Production in Africa (16) 3. Artemisinin: Extraction and Use in ACTs (98) a. Extraction of Artemisinin (20) b. Artemisinin Derivatives and ACTs (21) c. Additional ACT Combinations (23) d. Multiple Combinations and Terminology (23) 4. ACTs: Introduction and Implementation (24) a. Initial Availability of ACTs (24) b. Transition to ACTs in Africa (25) c. Development of Resistance to ACTs (26) d. Implications for Artemisinin Monotherapies (28) e. WHO Guidelines for the Use of ACTs (30) 5. Artemisinin Drugs: A Question of Efficacy (30) a. Counterfeit Artemisins (31) b. Substandard Artemisins (31) III. The Context: Supply, Demand, Subsidies, and Aid (33-51) 1. Technical Dimensions of Supply & Demand (33) a. Supply of Artemisia and Artemisinin (33) i. Artemisia: Area and Yield (33) ii. Artemisinin: Extractors and Extraction (34) b. Demand for Artemisinin: New ACTs (35) c. Related Considerations (35) i. Other Sources of Artemisinin (36) (a) New Plant Source (36) (b) New Derivative (36) (c) Chemical and Buological Synthesis (36) 4 ii. Need for a Different Type of Drug (38) iii. Other Methods of Control: Vaccines (37) d. Balancing Supply and Demand: Phase I (39) 2. National Policy and Multilateral Programs (40) a. National Adoption of ACTs (40) b. Multilateral Subsidy Programs (41) i. The Global Fund to Fight AIDS, Tuberculosis and Malaria (41) ii. The Affordable Medicines Facility for Malaria (42) iii. Similar Programmatic Constraints (45) 3. Bilateral Assistance & Multilateral Participation: USAID (47) IV. Policy Issues: Public, Public/Private, Social, and Program (52-75) 1. Public Needs, Public Goods, and Resource Allocation (52) a. Public Needs and Public Goods (52) b. Allocation of Public Resources (54) 2. Public/Private Interactions (54) a. The Overall Framework (56) i. Research (56) ii Subsidies (56) b. Balancing Supply and Demand: Phase II (58) i. Artemisia and Artemisinin (58) ii. Manufacture of ACTs (59) iii. Procurement and Use of ACTs (60) iv. Projections of Supply and Demand (60). v. Achieving a Better Balance (61) c. The Key Role of Diagnosis (63) 3. Social/Individual Interactions (64) a. Development of Resistance (64) b. Ethical Issues (65) c. Prevention or/and Cure? (67) 4. Program Implementation (69) a. Need for Parallel Actions (69) b. Proposals for Elimination and Eradication (71) c. Impact, Sustainability and Prospects (72) 5. Role of Economic Development (73) V. Concluding Remarks: The Wisdom of the Red Queen (76-77) 5 Annexes (78-104) 1. Artemisia: Role in Early Chinese History (78) 2. Artemisinin and ACTs: Chinese Acounts of Discovery & Development (80) 3. Artemisia: Genetic Resources and Varietal Improvement (83) a. Historical Background (83) b. Regions and Nations (84) c. Other Plant Sources of Antimalarials (87) 4. Artemisia: A Kenyan Grower’s Perspective (88) 5. Artemisia: Traditional Medicine and Science (89) a. Artemisia Teas (89) b. Herbal Therapies (90) c. Science and/or Tradition? (91) 6.
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