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Plasmodium vivax malaria remains a global health challenge, with approximately 6.9 million estimated cases in 2022. The parasite has a dormant liver stage, the hypnozoite, which reactivates to cause repeated relapses over weeks, months, or years. These relapses erode patient health, contribute to the burden of malaria, and promote transmission. Radical cure to prevent relapses requires administration of an 8-aminoquinoline, either primaquine or tafenoquine. However, malaria treatment guidelines updated by the World Health Organization (WHO) in October 2023 restrict primaquine use for women breastfeeding children < 6 months of age, or women breastfeeding older children if their child is G6PD deficient or if the child's G6PD status is unknown. Primaquine restrictions assume that 8-aminoquinoline exposures in breast milk would be sufficient to cause haemolysis in the nursing infant should they be G6PD deficient. WHO recommendations for tafenoquine are awaited. Notably, the WHO recommends that infants are breastfed for the first 2 years of life, and exclusively until 6 months old. Repeated pregnancies, followed by extended breastfeeding leaves women in P. vivax endemic regions potentially vulnerable to relapses for many years. This puts women's health at risk, increases the malaria burden, and perpetuates transmission, hindering malaria control and elimination. The benefits of lifting restrictions on primaquine administration to breastfeeding women are significant, avoiding the adverse consequences of repeated episodes of acute malaria, such as severe anaemia. Recent data challenge the restriction of primaquine in breastfeeding women. Clinical pharmacokinetic data in breastfeeding infants ≥ 28 days old show that the exposure to primaquine is very low and less than 1% of the maternal exposure, indicating negligible risk to infants, irrespective of their G6PD status. Physiologically-based pharmacokinetic modelling complements the clinical data, predicting minimal primaquine exposure to infants and neonates via breast milk from early post-partum. This article summarizes the clinical and modelling evidence for a favourable benefit:risk evaluation of P. vivax radical cure with primaquine for breastfeeding women without the need for infant G6PD testing, supporting a change in policy. This adjustment to current treatment guidelines would support health equity in regard to effective interventions to protect women and their children, enhance malaria control strategies, and advance P. vivax elimination., (© 2024. The Author(s).)

Background: Prevention of Plasmodium vivax malaria recurrence is essential for malaria elimination in Brazil. We evaluated the real-world effectiveness of an updated treatment algorithm for P vivax radical cure in the Brazilian Amazon., Methods: In this non-interventional observational study, we used retrospective data from the implementation of a P vivax treatment algorithm at 43 health facilities in Manaus and Porto Velho, Brazil. The treatment algorithm consisted of chloroquine (25 mg/kg over 3 days) and point-of-care quantitative glucose-6-phosphate dehydrogenase (G6PD) testing followed by single-dose tafenoquine 300 mg (G6PD normal, aged ≥16 years, not pregnant and not breastfeeding), 7-day primaquine 0·5 mg/kg per day (G6PD intermediate or normal, aged ≥6 months, not pregnant, and not breastfeeding or breastfeeding for >1 month), or primaquine 0·75 mg/kg per week for 8 weeks (G6PD deficient, aged ≥6 months, not pregnant, and not breastfeeding or breastfeeding for >1 month). P vivax recurrences were identified from probabilistic linkage of routine patient records from the Brazilian malaria epidemiological surveillance system. Recurrence-free effectiveness at day 90 and day 180 was estimated using Kaplan-Meier analysis and hazard ratios (HRs) by multivariate analysis. This clinical trial is registered with ClinicalTrials.gov, NCT05096702, and is completed., Findings: Records from Sept 9, 2021, to Aug 31, 2022, included 5554 patients with P vivax malaria. In all treated patients of any age and any G6PD status, recurrence-free effectiveness at day 180 was 75·8% (95% CI 74·0-77·6) with tafenoquine, 73·4% (71·9-75·0) with 7-day primaquine, and 82·1% (77·7-86·8) with weekly primaquine. In patients aged at least 16 years who were G6PD normal, recurrence-free effectiveness until day 90 was 88·6% (95% CI 87·2-89·9) in those who were treated with tafenoquine (n=2134) and 83·5% (79·8-87·4) in those treated with 7-day primaquine (n=370); after adjustment for confounding factors, the HR for recurrence following tafenoquine versus 7-day primaquine was 0·65 (95% CI 0·49-0·86; p=0·0031), with similar outcomes between the two treatments at day 180 (log-rank p=0·82). Over 180 days, median time to recurrence in patients aged at least 16 years who were G6PD normal was 92 days (IQR 76-120) in those treated with tafenoquine and 68 days (52-94) in those treated with 7-day primaquine., Interpretation: In this real-world setting, single-dose tafenoquine was more effective at preventing P vivax recurrence in patients aged at least 16 years who were G6PD normal compared with 7-day primaquine at day 90, while overall efficacy at 180 days was similar. The public health benefits of the P vivax radical cure treatment algorithm incorporating G6PD quantitative testing and tafenoquine support its implementation in Brazil and potentially across South America., Funding: Brazilian Ministry of Health, Municipal and State Health Secretariats; Fiocruz; Medicines for Malaria Venture; Bill & Melinda Gates Foundation; Newcrest Mining; and the UK Government., Translation: For the Portuguese translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests SD, PGD, IB-F, and EJ are employees of Medicines for Malaria Venture. DBP declares grants from Butantan, PATH, and Janssen, payment for lectures or presentations from GSK, and support for attending meetings and travel from Janssen. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: To achieve malaria elimination, Brazil must implement Plasmodium vivax radical cure. We aimed to investigate the operational feasibility of point-of-care, quantitative, glucose-6-phosphate dehydrogenase (G6PD) testing followed by chloroquine plus tafenoquine or primaquine., Methods: This non-interventional, observational study was done at 43 health facilities in Manaus (Amazonas State) and Porto Velho (Rondônia State), Brazil, implementing a new P vivax treatment algorithm incorporating point-of-care quantitative G6PD testing to identify G6PD status and single-dose tafenoquine (G6PD normal, aged ≥16 years, and not pregnant or breastfeeding) or primaquine (intermediate or normal G6PD, aged ≥6 months, not pregnant, or breastfeeding >1 month). Following training of health-care providers, we collated routine patient records from the malaria epidemiological surveillance system (SIVEP-Malaria) retrospectively for all consenting patients aged at least 6 months with parasitologically confirmed P vivax malaria mono-infection or P vivax plus P falciparum mixed infection, presenting between Sept 9, 2021, and Aug 31, 2022. The primary endpoint was the proportion of patients aged at least 16 years with P vivax mono-infection treated or not treated appropriately with tafenoquine in accordance with their G6PD status. The trial is registered with ClinicalTrials.gov, NCT05096702, and is completed., Findings: Of 6075 patients enrolled, 6026 (99·2%) had P vivax mono-infection, 2685 (44·6%) of whom were administered tafenoquine. G6PD status was identified in 2685 (100%) of 2685 patients treated with tafenoquine. The proportion of patients aged at least 16 years with P vivax mono-infection who were treated or not treated appropriately with tafenoquine in accordance with their G6PD status was 99·7% (95% CI 99·4-99·8; 4664/4680)., Interpretation: Quantitative G6PD testing before tafenoquine administration was operationally feasible, with high adherence to the treatment algorithm, supporting deployment throughout the Brazilian health system., Funding: Brazilian Ministry of Health, Municipal and State Health Secretariats; Fiocruz; Medicines for Malaria Venture; Bill & Melinda Gates Foundation; Newcrest Mining; and the UK Government., Translation: For the Portuguese translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests SD, PGD, IB-F, and EJ are employed by Medicines for Malaria Venture. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

The delivery of safe and effective radical cure for Plasmodium vivax is one of the greatest challenges for achieving malaria elimination from the Asia-Pacific by 2030. During the annual meeting of the Asia Pacific Malaria Elimination Network Vivax Working Group in October 2016, a round table discussion was held to discuss the programmatic issues hindering the widespread use of primaquine (PQ) radical cure. Participants included 73 representatives from 16 partner countries and 33 institutional partners and other research institutes. In this meeting report, the key discussion points are presented and grouped into five themes: (i) current barriers for glucose-6-phosphate deficiency (G6PD) testing prior to PQ radical cure, (ii) necessary properties of G6PD tests for wide scale deployment, (iii) the promotion of G6PD testing, (iv) improving adherence to PQ regimens and (v) the challenges for future tafenoquine (TQ) roll out. Robust point of care (PoC) G6PD tests are needed, which are suitable and cost-effective for clinical settings with limited infrastructure. An affordable and competitive test price is needed, accompanied by sustainable funding for the product with appropriate training of healthcare staff, and robust quality control and assurance processes. In the absence of quantitative PoC G6PD tests, G6PD status can be gauged with qualitative diagnostics, however none of the available tests is currently sensitive enough to guide TQ treatment. TQ introduction will require overcoming additional challenges including the management of severely and intermediately G6PD deficient individuals. Robust strategies are needed to ensure that effective treatment practices can be deployed widely, and these should ensure that the caveats are outweighed by  the benefits of radical cure for both the patients and the community. Widespread access to quality controlled G6PD testing will be critical.

Falsified and substandard medicines present serious concerns for public health. We describe an event that occurred in late 2011 involving falsified antiretroviral medicines found in the supplies of Médecins Sans Frontières (MSF) projects in Kenya. We discuss factors contributing to these falsified medicines entering the supply chain as well as the response by MSF and others. We make recommendations to help defend against future episodes of entry of falsified medicines into the supply chain as well as comments on appropriate responses in cases of falsified medicines.

Background: Tiered pricing - the concept of selling drugs and vaccines in developing countries at prices systematically lower than in industrialized countries - has received widespread support from industry, policymakers, civil society, and academics as a way to improve access to medicines for the poor. We carried out case studies based on a review of international drug price developments for antiretrovirals, artemisinin combination therapies, drug-resistant tuberculosis medicines, liposomal amphotericin B (for visceral leishmaniasis), and pneumococcal vaccines., Discussion: We found several critical shortcomings to tiered pricing: it is inferior to competition for achieving the lowest sustainable prices; it often involves arbitrary divisions between markets and/or countries, which can lead to very high prices for middle-income markets; and it leaves a disproportionate amount of decision-making power in the hands of sellers vis-à-vis consumers. In many developing countries, resources are often stretched so tight that affordability can only be approached by selling medicines at or near the cost of production. Policies that "de-link" the financing of R&D from the price of medicines merit further attention, since they can reward innovation while exploiting robust competition in production to generate the lowest sustainable prices. However, in special cases - such as when market volumes are very small or multi-source production capacity is lacking - tiered pricing may offer the only practical option to meet short-term needs for access to a product. In such cases, steps should be taken to ensure affordability and availability in the longer-term., Summary: To ensure access to medicines for populations in need, alternate strategies should be explored that harness the power of competition, avoid arbitrary market segmentation, and/or recognize government responsibilities. Competition should generally be the default option for achieving affordability, as it has proven superior to tiered pricing for reliably achieving the lowest sustainable prices.

Background: Important advances in the development and production of quality-certified pediatric antiretroviral (ARV) formulations have recently been made despite significant market disincentives for manufacturers. This progress resulted from lobbying and innovative interventions from HIV/AIDS activists, civil society organizations, and international organizations. Research on uptake and dispersion of these improved products across countries and international organizations has not been conducted but is needed to inform next steps towards improving child health., Methods: We used information from the World Health Organization Prequalification Programme and the United States Food and Drug Administration to describe trends in quality-certification of pediatric formulations and used 7,989 donor-funded, pediatric ARV purchase transactions from 2002-2009 to measure uptake and dispersion of new pediatric ARV formulations across countries and programs. Prices for new pediatric ARV formulations were compared to alternative dosage forms., Results: Fewer ARV options exist for HIV/AIDS treatment in children than adults. Before 2005, most pediatric ARVs were produced by innovator companies in single-component solid and liquid forms. Five 2-in1 and four 3-in-1 generic pediatric fixed-dose combinations (FDCs) in solid and dispersible forms have been quality-certified since 2005. Most (67%) of these were produced by one quality-certified manufacturer. Uptake of new pediatric FDCs outside of UNITAID is low. UNITAID accounted for 97-100% of 2008-2009 market volume. In total, 33 and 34 countries reported solid or dispersible FDC purchases in 2008 and 2009, respectively, but most purchases were made through UNITAID. Only three Global Fund country recipients reported purchase of these FDCs in 2008. Prices for pediatric FDCs were considerably lower than liquids but typically higher than half of an adult FDC., Conclusion: Pediatric ARV markets are more fragile than adult markets. Ensuring a long-term supply of quality, well-adapted ARVs for children requires ongoing monitoring and improved understanding of global pediatric markets, including country-based research to explain and address low uptake of new, improved formulations. Continued innovation in pediatric ARV development may be threatened by outdated procurement practices failing to connect clinicians making prescribing decisions, supply chain staff dealing with logistics, donors, international organizations, and pharmaceutical manufacturers. Perceptions of global demand must be better informed by accurate estimates of actual country-level demand.

Financial access to HIV care and treatment can be difficult for many people in China, where the government provides free antiretroviral drugs but does not cover the cost of other medically necessary components, such as lab tests and drugs for opportunistic infections. This article estimates out-of-pocket costs for treatment and care that a person living with HIV/AIDS in China might face over the course of one year. Data comes from two treatment projects run by Médecins Sans Frontières in Nanning, Guangxi Province and Xiangfan, Hubei Province. Based on the national treatment guidelines, we estimated costs for seven different patient profiles ranging from WHO Clinical Stages I through IV. We found that patients face significant financial barriers to even qualify for the free ARV program. For those who do, HIV care and treatment can be a catastrophic health expenditure, with cumulative patient contributions ranging from approximately US$200-3939/year in Nanning and US$13-1179/year in Xiangfan, depending on the patient's clinical stage of HIV infection. In Nanning, these expenses translate as up to 340% of an urban resident's annual income or 1200% for rural residents; in Xiangfan, expenses rise to 116% of annual income for city dwellers and 295% in rural areas. While providing ARV drugs free of charge is an important step, the costs of other components of care constitute important financial barriers that may exclude patients from accessing appropriate care. Such barriers can also lead to undesirable outcomes in the future, such as impoverishment of AIDS-affected households, higher ARV drug-resistance rates and greater need for complex, expensive second-line antiretroviral drugs.

This study was set up to document the variability of prescribing information from different sources concerning indications, side effects and cautions of selected drugs. An original method to measure the degree of information agreement among different written materials, such as summaries of product characteristics, package inserts and data sheets, and a widely accepted reference text was developed. The results show that there is substantial disagreement in the materials available to prescribers and patients in different countries. Disagreement was even found within a single country when written materials from different brands of the same drug were compared. The discordance can be explained by the fact that the evidence available for each drug is considered/assessed differently by separate countries. It is argued that the discrepancies found may mislead prescribers, patients and those comparing drug-use patterns across countries. National regulatory authorities have a key role to play in remedying this situation, and a two-pronged approach is proposed. At the international level, national authorities should strengthen collaboration and information interchange and, at the national level, should implement appropriate measures aimed at removing contradictory statements on drug-information materials that have no reason to be different. Finally, further training and continued education aimed at drug regulatory officials could provide the necessary knowledge and enable national authorities to meet the need for drug information that is independent of commercial interests.