Quantifying primaquine effectiveness and improving adherence: a round table discussion of the APMEN Vivax Working Group

Kamala Thriemer, Albino Bobogare, Benedikt Ley, Clarice Samo Gudo, Mohammad Shafiul Alam, Nick M. Anstey, Elizabeth Ashley, J. Kevin Baird, Charlotte Gryseels, Elodie Jambert, Marcus Lacerda, Ferdinand Laihad, Jutta Marfurt, Ayodhia Pitaloka Pasaribu, Jeanne Rini Poespoprodjo, Inge Sutanto, Walter R. Taylor, Christel van den Boogaard, Katherine E. Battle, Lek Dysoley, Prakash Ghimire, Bill Hawley, Jimee Hwang, Wasif Ali Khan, Rose Nani Binti Mudin, Maria Endang Sumiwi, Rukhsana Ahmed, M. M. Aktaruzzaman, Kiran Raj Awasthi, Azucena Bardaji, David Bell, Leonard Boaz, Faustina Helen Burdam, Daniel Chandramohan, Qin Cheng, Keobouphaphone Chindawongsa, Janice Culpepper, Santasabuj Das, Raffy Deray, Meghna Desai, Gonzalo Domingo, Wang Duoquan, Stephan Duparc, Rustini Floranita, Emily Gerth-Guyette, Rosalind E. Howes, Cecilia Hugo, George Jagoe, Elvieda Sariwati, Sanya Tahmina Jhora, Wu Jinwei, Harin Karunajeewa, Enny Kenangalem, Bibek Kumar Lal, Chandra Landuwulang, Emmanuel Le Perru, Sang-Eun Lee, Leo Sora Makita, James McCarthy, Asrat Mekuria, Neelima Mishra, Esau Naket, Simone Nambanya, Johnny Nausien, Thang Ngo Duc, Thuan Nguyen Thi, Rinitis Noviyanti, Daniel Pfeffer, Gao Qi, Annisa Rahmalia, Stephen Rogerson, Iriani Samad, Jetsumon Sattabongkot, Ari Satyagraha, Dennis Shanks, Surender Nath Sharma, Carol Hopkins Sibley, Ali Sungkar, Din Syafruddin, Arunansu Talukdar, Joel Tarning, Feiko ter Kuile, Suman Thapa, Minerva Theodora, Tho Tran Huy, Edward Waramin, Govert Waramori, Adugna Woyessa, Chansuda Wongsrichanalai, Nguyen Xuan Xa, Joon Sup Yeom, Lukas Hermawan, Angela Devine, Spike Nowak, Indra Jaya, Supargiyono Supargiyono, Koen Peeters Grietens, Ric N. Price

The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness.