register interest

Professor Trudie Lang

Research Area: Global Health
Technology Exchange: Drug discovery and Medical statistics
Scientific Themes: Tropical Medicine & Global Health and Clinical Trials & Epidemiology
Keywords: clinical trials, GCP, Informed consent, Trial design, Trial operations and Trial regulations
Web Links:

The Global Health Network

Principal Investigator Trudie Lang

Global Health Network accelerates and streamlines research through an innovative digital community, facilitating collaboration and resource sharing across global health

Background

Clinical research brings evidence base for prevention and treatment of disease and is critically important in the field of Global Health. This importance is threefold: there is the greatest potential for improving health in numerical terms, there is enormous potential gain from relatively simple interventions, and developing countries have been under represented in clinical studies to date.
Clinical trials in developing countries typically have endpoints that are severe disease outcomes or mortality. They more often involve children and are sponsored by not-for-profit organisations. There are also specific situations that merit more and better clinical trials to inform policy such as disease outbreaks, including those with pandemic potential, in displaced populations, refugee camps and natural disasters. These very specialist situations and environments need a research focus in order to identify highly practical and appropriate interpretation of guidelines and regulations to enable rapid and flexible trial implementation whilst maintaining the same degree of attention to ethical standards and to quality of processes and data as any international trial.
There is a high level of activity with externally sponsored product development trials. However disease management trials are equally important and product development trials alone do not leave sites with the ability to run their own broad programmes. To encourage more locally led trials we need to support researchers and provide skills and guidance in setting questions and operating protocols.

Objectives

We have established a dedicated and collaborative online science park. Global Health Network is a one-stop shop for sharing research methods and facilitating collaboration among global health professionals to fuel faster and better evidence to improve health in resource-limited settings

One of the areas within The Global Health Network is a cross-cutting resource called Global Health Trials which is  forum to help clinical researchers with trial operations, design, methods and interpretation of regulations. Global Health Trials offers guidance whilst also identifying problems and potential solutions and encouraging the sharing of best practices. Using a participatory mixed methods action research approach we are conducting methodology research to identify the real barriers and issues. The data gathered is being used to continuously update the web forum and to develop resources and guidance to enable the conduct of clinical trials to be both appealing and straightforward.

The main objective of this research is to identify where the interpretation of GCP and other regulatory requirements is problematic in resource poor settings and quantify the impact these issues are having. The identification of the problems will lead to studies that will generate new tools that will be made available on the web forum. This is a continuous iterative process so continuing the theme of participatory action research, with the web forum providing the open-access, open source and fully collaborative vehicle.

There is a need for well trained and qualified clinical trialists to lead and design their own trial programmes in developing countries in order to catch up with the career structures in the west. Therefore another aim of this collaboration is to develop training courses and resources to meet specific gaps. At present there are diplomas and MSc clinical trial courses that are taught and available through distance learning. Whilst these are good, they are focused on industry and US/European regulatory needs. Our research will also help to guide the design and content of courses specifically focused on developing country clinical trials based on what we have shown to work locally in vulnerable populations.
Our findings will also enable funders interested in capacity building to direct their resources appropriately and product developers to select trial sites. Although we are focusing our research on tropical medicine we expect some of our findings to be generally applicable to anyone engaged in non-commercial trials.

Name Department Institution Country
Kathryn Maitland FEAST trial Kenya
Kathryn Maitland FEAST trial Uganda
Kathryn Maitland FEAST trial Tanzania
Dr Raghib Ali MRCP University of Oxford United Kingdom
Professor Jeremy Farrar Tropical Medicine University of Oxford United Kingdom
Professor Rosanna Peeling London School Hygiene and Tropical Medicine United Kingdom
Professor Catherine (Sassy) Molyneux Tropical Medicine University of Oxford United Kingdom
Whitehead J, Olliaro P, Lang T, Horby P. 2016. Trial design for evaluating novel treatments during an outbreak of an infectious disease. Clin Trials, 13 (1), pp. 31-38. | Show Abstract | Read more

Tragically, the outbreak of Ebola that started in West Africa in 2014 has been far more extensive and damaging than any previous outbreaks. The duration of the outbreak has, for the first time, allowed the clinical evaluation of Ebola treatments. This article discusses the designs used for two such clinical trials which have recruited patients in Liberia and Sierra Leone. General principles are outlined for trial designs intended to be deployed quickly, adapt flexibly and provide results soon enough to influence the course of the current epidemic rather than just providing evidence for use should Ebola break out again. Lessons are drawn for the conduct of clinical research in future outbreaks of infectious diseases, where the sequence of events may or may not be similar to the West African Ebola epidemic.

Jule A, Garba A, Guerin P, Lang T, Olliaro P. 2015. Building a data-sharing platform for schistosomiasis treatment data: opportunities and challenges TROPICAL MEDICINE & INTERNATIONAL HEALTH, 20 pp. 228-229.

Lang T. 2015. Embed research in outbreak response NATURE, 524 (7563), pp. 29-31.

Lang T. 2015. Ebola: Embed research in outbreak response. Nature, 524 (7563), pp. 29-31. | Read more

Treweek S, Altman DG, Bower P, Campbell M, Chalmers I, Cotton S, Craig P, Crosby D et al. 2015. Making randomised trials more efficient: report of the first meeting to discuss the Trial Forge platform. Trials, 16 (1), pp. 261. | Show Abstract | Read more

Randomised trials are at the heart of evidence-based healthcare, but the methods and infrastructure for conducting these sometimes complex studies are largely evidence free. Trial Forge ( www.trialforge.org ) is an initiative that aims to increase the evidence base for trial decision making and, in doing so, to improve trial efficiency.This paper summarises a one-day workshop held in Edinburgh on 10 July 2014 to discuss Trial Forge and how to advance this initiative. We first outline the problem of inefficiency in randomised trials and go on to describe Trial Forge. We present participants' views on the processes in the life of a randomised trial that should be covered by Trial Forge.General support existed at the workshop for the Trial Forge approach to increase the evidence base for making randomised trial decisions and for improving trial efficiency. Agreed upon key processes included choosing the right research question; logistical planning for delivery, training of staff, recruitment, and retention; data management and dissemination; and close down. The process of linking to existing initiatives where possible was considered crucial. Trial Forge will not be a guideline or a checklist but a 'go to' website for research on randomised trials methods, with a linked programme of applied methodology research, coupled to an effective evidence-dissemination process. Moreover, it will support an informal network of interested trialists who meet virtually (online) and occasionally in person to build capacity and knowledge in the design and conduct of efficient randomised trials.Some of the resources invested in randomised trials are wasted because of limited evidence upon which to base many aspects of design, conduct, analysis, and reporting of clinical trials. Trial Forge will help to address this lack of evidence.

Cooper BS, Boni MF, Pan-ngum W, Day NP, Horby PW, Olliaro P, Lang T, White NJ, White LJ, Whitehead J. 2015. Evaluating clinical trial designs for investigational treatments of Ebola virus disease. PLoS Med, 12 (4), pp. e1001815. | Show Abstract | Read more

BACKGROUND: Experimental treatments for Ebola virus disease (EVD) might reduce EVD mortality. There is uncertainty about the ability of different clinical trial designs to identify effective treatments, and about the feasibility of implementing individually randomised controlled trials during an Ebola epidemic. METHODS AND FINDINGS: A treatment evaluation programme for use in EVD was devised using a multi-stage approach (MSA) with two or three stages, including both non-randomised and randomised elements. The probabilities of rightly or wrongly recommending the experimental treatment, the required sample size, and the consequences for epidemic outcomes over 100 d under two epidemic scenarios were compared for the MSA, a sequential randomised controlled trial (SRCT) with up to 20 interim analyses, and, as a reference case, a conventional randomised controlled trial (RCT) without interim analyses. Assuming 50% 14-d survival in the population treated with the current standard of supportive care, all designs had similar probabilities of identifying effective treatments correctly, while the MSA was less likely to recommend treatments that were ineffective. The MSA led to a smaller number of cases receiving ineffective treatments and faster roll-out of highly effective treatments. For less effective treatments, the MSA had a high probability of including an RCT component, leading to a somewhat longer time to roll-out or rejection. Assuming 100 new EVD cases per day, the MSA led to between 6% and 15% greater reductions in epidemic mortality over the first 100 d for highly effective treatments compared to the SRCT. Both the MSA and SRCT led to substantially fewer deaths than a conventional RCT if the tested interventions were either highly effective or harmful. In the proposed MSA, the major threat to the validity of the results of the non-randomised components is that referral patterns, standard of care, or the virus itself may change during the study period in ways that affect mortality. Adverse events are also harder to quantify without a concurrent control group. CONCLUSIONS: The MSA discards ineffective treatments quickly, while reliably providing evidence concerning effective treatments. The MSA is appropriate for the clinical evaluation of EVD treatments.

Horby PW, Endzt H, Muyembe-Tamfum JJ, van Griensven J, Gevao S, Goossens H, Malvy D, Haba NY et al. 2015. Ebola: Europe-Africa research collaborations. Lancet Infect Dis, 15 (11), pp. 1258-1259. | Read more

Negussie H, Kassahun MM, Fegan G, Njuguna P, Enquselassie F, McKay A, Newport M, Lang T, Davey G. 2015. Podoconiosis treatment in northern Ethiopia (GoLBet): study protocol for a randomised controlled trial. Trials, 16 (1), pp. 307. | Show Abstract | Read more

BACKGROUND: Podoconiosis is one of the forgotten types of leg swelling (elephantiasis) in the tropics. Unlike the other, better-known types of leg swelling, podoconiosis is not caused by any parasite, virus or bacterium, but by an abnormal reaction to minerals found in the clay soils of some tropical highland areas. Non-governmental Organizations (NGOs) have been responsible for the development of simple treatment methods without systematic evaluation of its effectiveness. It is essential that a large scale, fully controlled, pragmatic trial of the intervention is conducted. We aim to test the hypothesis that community-based treatment of podoconiosis lymphoedema reduces the frequency of acute dermatolymphangioadenitis episodes ('acute attacks') and improves other clinical, social and economic outcomes. METHODS/DESIGN: This is a pragmatic, individually randomised controlled trial. We plan to randomly allocate 680 podoconiosis patients from the East Gojjam Zone in northern Ethiopia to one of two groups: 'Standard Treatment' or 'Delayed Treatment'. Those randomised to standard treatment will receive the hygiene and foot-care intervention from May 2015 for one year, whereas those in the control arm will be followed through 2015 and be offered the intervention in 2016. The trial will be preceded by an economic context survey and a Rapid Ethical Assessment to identify optimal methods of conveying information about the trial and the approaches to obtaining informed consent preferred by the community. The primary outcome will be measured by recording patient recall and using a simple, patient-held diary that will be developed to record episodes of acute attacks. Adherence to treatment, clinical stage of disease, quality of life, disability and stigma will be considered secondary outcome measures. Other outcomes will include adverse events and economic productivity. Assessments will be made at baseline and at 3, 6, 9 and 12 months thereafter. DISCUSSION: The evidence is highly likely to inform implementation of the new master plan for integrated control of Neglected Tropical Diseases (NTDs), in which podoconiosis is identified as one of eight NTDs prioritised for control. Potentially, an estimated 3 million patients in Ethiopia will therefore benefit from the results of this trial. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number. REGISTRATION NUMBER: ISRCTN67805210. Date of registration: 24 January 2013.

Furtado T, Franzen S, van Loggerenberg F, Carn G, Grahek S, McBride M, Power M, O'Reilly J et al. 2014. Strengthening neglected tropical disease research through enhancing research-site capacity: an evaluation of a novel web application to facilitate research collaborations. PLoS Negl Trop Dis, 8 (11), pp. e3225. | Read more

Chantler T, Cheah PY, Miiro G, Hantrakum V, Nanvubya A, Ayuo E, Kivaya E, Kidola J et al. 2014. International health research monitoring: exploring a scientific and a cooperative approach using participatory action research. BMJ Open, 4 (2), pp. e004104. | Show Abstract | Read more

OBJECTIVES: To evaluate and determine the value of monitoring models developed by the Mahidol Oxford Tropical Research Unit and the East African Consortium for Clinical Research, consider how this can be measured and explore monitors' and investigators' experiences of and views about the nature, purpose and practice of monitoring. RESEARCH DESIGN: A case study approach was used within the context of participatory action research because one of the aims was to guide and improve practice. 34 interviews, five focus groups and observations of monitoring practice were conducted. SETTING AND PARTICIPANTS: Fieldwork occurred in the places where the monitoring models are coordinated and applied in Thailand, Cambodia, Uganda and Kenya. Participants included those coordinating the monitoring schemes, monitors, senior investigators and research staff. ANALYSIS: Transcribed textual data from field notes, interviews and focus groups was imported into a qualitative data software program (NVIVO V. 10) and analysed inductively and thematically by a qualitative researcher. The initial coding framework was reviewed internally and two main categories emerged from the subsequent interrogation of the data. RESULTS: The categories that were identified related to the conceptual framing and nature of monitoring, and the practice of monitoring, including relational factors. Particular emphasis was given to the value of a scientific and cooperative style of monitoring as a means of enhancing data quality, trust and transparency. In terms of practice the primary purpose of monitoring was defined as improving the conduct of health research and increasing the capacity of researchers and trial sites. CONCLUSIONS: The models studied utilise internal and network wide expertise to improve the ethics and quality of clinical research. They demonstrate how monitoring can be a scientific and constructive exercise rather than a threatening process. The value of cooperative relations needs to be given more emphasis in monitoring activities, which seek to ensure that research protects human rights and produces reliable data.

Lang T, Marsh K, Peeling R, Farrar J. 2013. Sharing methods for global health research: an assessment of methodology LANCET, 382 pp. 5-5.

Franzen SRP, Chandler C, Atashili J, Angus B, Lang T. 2013. Barriers and enablers of locally led clinical trials in Ethiopia and Cameroon: a prospective, qualitative study LANCET, 382 pp. 14-14.

Franzen SR, Chandler C, Enquselassie F, Siribaddana S, Atashili J, Angus B, Lang T. 2013. Understanding the investigators: a qualitative study investigating the barriers and enablers to the implementation of local investigator-initiated clinical trials in Ethiopia. BMJ Open, 3 (11), pp. e003616. | Show Abstract | Read more

OBJECTIVES: Clinical trials provide 'gold standard' evidence for policy, but insufficient locally relevant trials are conducted in low-income and middle-income countries. Local investigator-initiated trials could generate highly relevant data for national governments, but information is lacking on how to facilitate them. We aimed to identify barriers and enablers to investigator-initiated trials in Ethiopia to inform and direct capacity strengthening initiatives. DESIGN: Exploratory, qualitative study comprising of in-depth interviews (n=7) and focus group discussions (n=3). SETTING: Fieldwork took place in Ethiopia during March 2011. PARTICIPANTS: Local health researchers with previous experiences of clinical trials or stakeholders with an interest in trials were recruited through snowball sampling (n=20). OUTCOME MEASURES: Detailed discussion notes were analysed using thematic coding analysis and key themes were identified. RESULTS: All participants perceived investigator-initiated trials as important for generating local evidence. System and organisational barriers included: limited funding allocation, weak regulatory and administrative systems, few learning opportunities, limited human and material capacity and poor incentives for conducting research. Operational hurdles were symptomatic of these barriers. Lack of awareness, confidence and motivation to undertake trials were important individual barriers. Training, knowledge sharing and experience exchange were key enablers to trial conduct and collaboration was unanimously regarded as important for improving capacity. CONCLUSIONS: Barriers to trial conduct were found at individual, operational, organisational and system levels. These findings indicate that to increase locally led trial conduct in Ethiopia, system wide changes are needed to create a more receptive and enabling research environment. Crucially, the creation of research networks between potential trial groups could provide much needed practical collaborative support through sharing of financial and project management burdens, knowledge and resources. These findings could have important implications for capacity-strengthening initiatives but further research is needed before the results can be generalised more widely.

Lang T, Siribaddana S. 2012. Clinical trials have gone global: is this a good thing? PLoS Med, 9 (6), pp. e1001228. | Read more

Lang T. 2012. Using digital technology to support and enhance clinical trials in resource-limited settings TROPICAL MEDICINE & INTERNATIONAL HEALTH, 17 pp. 49-49.

Lang T. 2011. Adaptive trial design: could we use this approach to improve clinical trials in the field of global health? Am J Trop Med Hyg, 85 (6), pp. 967-970. | Show Abstract | Read more

We need more clinical trials in the world's poorest regions to evaluate new drugs and vaccines, and also to find better ways to manage health issues. Clinical trials are expensive, time consuming, and cumbersome. However, in wealthier regions these limiting factors are being addressed to make trials less administrative and improve the designs. A good example is adaptive trial design. This innovation is becoming accepted by the regulators and has been taken up by the pharmaceutical industry to reduce product development times and costs. If this approach makes trials easier and less expensive surely we should be implementing this approach in the field of tropical medicine and international health? As yet this has rarely been proposed and there are few examples. There is a need for raising the awareness of these design approaches because they could be used to make dramatic improvements to clinical research in developing countries.

Boga M, Davies A, Kamuya D, Kinyanjui SM, Kivaya E, Kombe F, Lang T, Marsh V et al. 2011. Strengthening the informed consent process in international health research through community engagement: The KEMRI-Wellcome Trust Research Programme Experience. PLoS Med, 8 (9), pp. e1001089. | Read more

Mbuagbaw L, Thabane L, Ongolo-Zogo P, Lang T. 2011. The challenges and opportunities of conducting a clinical trial in a low resource setting: the case of the Cameroon mobile phone SMS (CAMPS) trial, an investigator initiated trial. Trials, 12 (1), pp. 145. | Show Abstract | Read more

Conducting clinical trials in developing countries often presents significant ethical, organisational, cultural and infrastructural challenges to researchers, pharmaceutical companies, sponsors and regulatory bodies. Globally, these regions are under-represented in research, yet this population stands to gain more from research in these settings as the burdens on health are greater than those in developed resourceful countries. However, developing countries also offer an attractive setting for clinical trials because they often have larger treatment naive populations with higher incidence rates of disease and more advanced stages. These factors can present a reduction in costs and time required to recruit patients. So, balance needs to be found where research can be encouraged and supported in order to bring maximum public health benefits to these communities. The difficulties with such trials arise from problems with obtaining valid informed consent, ethical compensation mechanisms for extremely poor populations, poor health infrastructure and considerable socio-economic and cultural divides. Ethical concerns with trials in developing countries have received attention, even though many other non-ethical issues may arise. Local investigator initiated trials also face a variety of difficulties that have not been adequately reported in literature. This paper uses the example of the Cameroon Mobile Phone SMS trial to describe in detail, the specific difficulties encountered in an investigator-initiated trial in a developing country. It highlights administrative, ethical, financial and staff related issues, proposes solutions and gives a list of additional documentation to ease the organisational process.

Porter DW, Thompson FM, Berthoud TK, Hutchings CL, Andrews L, Biswas S, Poulton I, Prieur E et al. 2011. A human Phase I/IIa malaria challenge trial of a polyprotein malaria vaccine. Vaccine, 29 (43), pp. 7514-7522. | Show Abstract | Read more

We examined the safety, immunogenicity and efficacy of a prime-boost vaccination regime involving two poxvirus malaria subunit vaccines, FP9-PP and MVA-PP, expressing the same polyprotein consisting of six pre-erythrocytic antigens from Plasmodium falciparum. Following safety assessment of single doses, 15 volunteers received a heterologous prime-boost vaccination regime and underwent malaria sporozoite challenge. The vaccines were safe but interferon-γ ELISPOT responses were low compared to other poxvirus vectors, despite targeting multiple antigens. There was no vaccine efficacy as measured by delay in time to parasitaemia. A number of possible explanations are discussed, including the very large insert size of the polyprotein transgene.

Maitland K, Molyneux S, Boga M, Kiguli S, Lang T. 2011. Use of deferred consent for severely ill children in a multi-centre phase III trial. Trials, 12 (1), pp. 90. | Show Abstract | Read more

BACKGROUND: Voluntary participation of a subject in research respects a subject's rights, strengthens its ethical conduct, and is formalized by the informed consent process. Clinical trials of life-saving interventions for medical emergencies often necessitate enrollment of patients where prior written individual informed consent is impossible. Although there are regulations and guidelines on protecting subjects in emergency research, these have been criticised for being limited and unnecessarily restrictive. Across Europe and the United States stringent regulations have resulted in a substantial decline of clinical trials involving emergency interventions. METHODS: We are conducting a trial of fluid resuscitation in children with hypovolaemic shock in six hospitals across three malaria-endemic African countries. The design is pragmatic as children are enrolled on clinical criteria alone and is being conducted in hospitals with facilities typical of many district hospitals across Africa. The trial aims to inform strategy for managing children with febrile illness and features of shock. In order to develop appropriate consent processes for the trial, we conducted a narrative review of current international recommendations for emergency consent. RESULTS: Practical or specific guidance was generally sparse or confusing with few examples in the literature to direct our informed consent process. For a sub-group of children who were critically sick or where parents themselves were otherwise too distressed to consider prior written consent, we opted for a modified form of deferred consent. This included verbal assent from guardians at the point of enrollment, with full written consent obtained after stabilising the child. For children who died prior to full written consent, ethical permission was received to waiver full consent. CONCLUSIONS: In light of the controversy around guidance and regulations in this area we report how and why we have used a modified system of deferred consent in an emergency intervention trial in children. Although approved by all relevant ethics committees and operational in 3 countries in Africa, formal research is now necessary to explore the perceptions and experiences of parents, health workers, researchers and ethics committees of the modified method of deferred consent.

Lang T, Cheah PY, White NJ. 2011. Clinical research: time for sensible global guidelines. Lancet, 377 (9777), pp. 1553-1555. | Read more

Lang T. 2011. Advancing global health research through digital technology and sharing data. Science, 331 (6018), pp. 714-717. | Show Abstract | Read more

The imperative for improving health in the world's poorest regions lies in research, yet there is no question that low participation, a lack of trained staff, and limited opportunities for data sharing in developing countries impede advances in medical practice and public health knowledge. Extensive studies are essential to develop new treatments and to identify better ways to manage healthcare issues. Recent rapid advances in availability and uptake of digital technologies, especially of mobile networks, have the potential to overcome several barriers to collaborative research in remote places with limited access to resources. Many research groups are already taking advantage of these technologies for data sharing and capture, and these initiatives indicate that increasing acceptance and use of digital technology could promote rapid improvements in global medical science.

Cited:

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Scopus

Porter DW, Thompson FM, Berthoud TK, Hutchings CL, Andrews L, Biswas S, Poulton I, Prieur E et al. 2011. A human phase I/IIa malaria challenge trial of a polyprotein malaria vaccine Vaccine, 29 (43), pp. 7514-7522. | Show Abstract | Read more

We examined the safety, immunogenicity and efficacy of a prime-boost vaccination regime involving two poxvirus malaria subunit vaccines, FP9-PP and MVA-PP, expressing the same polyprotein consisting of six pre-erythrocytic antigens from Plasmodium falciparum. Following safety assessment of single doses, 15 volunteers received a heterologous prime-boost vaccination regime and underwent malaria sporozoite challenge. The vaccines were safe but interferon-γ ELISPOT responses were low compared to other poxvirus vectors, despite targeting multiple antigens. There was no vaccine efficacy as measured by delay in time to parasitaemia. A number of possible explanations are discussed, including the very large insert size of the polyprotein transgene. © 2011 Elsevier Ltd.

Chilengi R, Juma R, Abdallah AM, Bashraheil M, Lodenyo H, Nyakundi P, Anabwani E, Salim A et al. 2011. A phase I trial to evaluate the safety and pharmacokinetics of low-dose methotrexate as an anti-malarial drug in Kenyan adult healthy volunteers. Malar J, 10 (1), pp. 63. | Show Abstract | Read more

BACKGROUND: Previous investigations indicate that methotrexate, an old anticancer drug, could be used at low doses to treat malaria. A phase I evaluation was conducted to assess the safety and pharmacokinetic profile of this drug in healthy adult male Kenyan volunteers. METHODS: Twenty five healthy adult volunteers were recruited and admitted to receive a 5 mg dose of methotrexate/day/5 days. Pharmacokinetics blood sampling was carried out at 2, 4, 6, 12 and 24 hours following each dose. Nausea, vomiting, oral ulcers and other adverse events were solicited during follow up of 42 days. RESULTS: The mean age of participants was 23.9 ± 3.3 years. Adherence to protocol was 100%. No grade 3 solicited adverse events were observed. However, one case of transiently elevated liver enzymes, and one serious adverse event (not related to the product) were reported. The maximum concentration (C(max)) was 160-200 nM and after 6 hours, the effective concentration (C(eff)) was <150 nM. CONCLUSION: Low-dose methotraxate had an acceptable safety profile. However, methotrexate blood levels did not reach the desirable C(eff) of 250-400-nM required to clear malaria infection in vivo. Further dose finding and safety studies are necessary to confirm suitability of this drug as an anti-malarial agent.

Olotu A, Lusingu J, Leach A, Lievens M, Vekemans J, Msham S, Lang T, Gould J et al. 2011. Efficacy of RTS,S/AS01E malaria vaccine and exploratory analysis on anti-circumsporozoite antibody titres and protection in children aged 5-17 months in Kenya and Tanzania: a randomised controlled trial. Lancet Infect Dis, 11 (2), pp. 102-109. | Show Abstract | Read more

BACKGROUND: RTS,S/AS01E is the lead candidate malaria vaccine. We recently showed efficacy against clinical falciparum malaria in 5-17 month old children, during an average of 8 months follow-up. We aimed to assess the efficacy of RTS,S/AS01E during 15 months of follow-up. METHODS: Between March, 2007, and October, 2008, we enrolled healthy children aged 5-17 months in Kilifi, Kenya, and Korogwe, Tanzania. Computer-generated block randomisation was used to randomly assign participants (1:1) to receive three doses (at month 0, 1, and 2) of either RTS,S/AS01E or human diploid-cell rabies vaccine. The primary endpoint was time to first clinical malaria episode, defined as the presence of fever (temperature ≥37·5°C) and a Plasmodium falciparum density of 2500/μL or more. Follow-up was 12 months for children from Korogwe and 15 months for children from Kilifi. Primary analysis was per protocol. In a post-hoc modelling analysis we characterised the associations between anti-circumsporozoite antibodies and protection against clinical malaria episodes. This study is registered with ClinicalTrials.gov, number NCT00380393. FINDINGS: 894 children were assigned, 447 in each treatment group. In the per-protocol analysis, 82 of 415 children in the RTS,S/AS01E group and 125 of 420 in the rabies vaccine group had first or only clinical malaria episode by 12 months, vaccine efficacy 39·2% (95% CI 19·5-54·1, p=0·0005). At 15 months follow-up, 58 of 209 children in the RTS,S/AS01E group and 85 of 206 in the rabies vaccine group had first or only clinical malaria episode, vaccine efficacy 45·8% (24·1-61·3, p=0·0004). At 12 months after the third dose, anti-circumsporozoite antibody titre data were available for 390 children in the RTS,S/AS01E group and 391 in the rabies group. A mean of 15 months (range 12-18 months) data were available for 172 children in the RTS,S/AS01E group and 155 in the rabies group. These titres at 1 month after the third dose were not associated with protection, but titres at 6·5 months were. The level of protection increased abruptly over a narrow range of antibody concentrations. The most common adverse events were pneumonia, febrile convulsion, gastroenteritis, and P falciparum malaria. INTERPRETATION: RTS,S/AS01E confers sustained efficacy for at least 15 months and shows promise as a potential public health intervention against childhood malaria in malaria endemic countries. FUNDING: PATH Malaria Vaccine Initiative (MVI), GlaxoSmithKline.

Lusingu J, Olotu A, Leach A, Lievens M, Vekemans J, Olivier A, Benns S, Olomi R et al. 2010. Safety of the malaria vaccine candidate, RTS,S/AS01E in 5 to 17 month old Kenyan and Tanzanian Children. PLoS One, 5 (11), pp. e14090. | Show Abstract | Read more

The malaria vaccine candidate, RTS,S/AS01(E), showed promising protective efficacy in a trial of Kenyan and Tanzanian children aged 5 to 17 months. Here we report on the vaccine's safety and tolerability. The experimental design was a Phase 2b, two-centre, double-blind (observer- and participant-blind), randomised (1∶1 ratio) controlled trial. Three doses of study or control (rabies) vaccines were administered intramuscularly at 1 month intervals. Solicited adverse events (AEs) were collected for 7 days after each vaccination. There was surveillance and reporting for unsolicited adverse events for 30 days after each vaccination. Serious adverse events (SAEs) were recorded throughout the study period which lasted for 14 months after dose 1 in Korogwe, Tanzania and an average of 18 months post-dose 1 in Kilifi, Kenya. Blood samples for safety monitoring of haematological, renal and hepatic functions were taken at baseline, 3, 10 and 14 months after dose 1. A total of 894 children received RTS,S/AS01(E) or rabies vaccine between March and August 2007. Overall, children vaccinated with RTS,S/AS01(E) had fewer SAEs (51/447) than children in the control group (88/447). One SAE episode in a RTS,S/AS01(E) recipient and nine episodes among eight rabies vaccine recipients met the criteria for severe malaria. Unsolicited AEs were reported in 78% of subjects in the RTS,S/AS01(E) group and 74% of subjects in the rabies vaccine group. In both vaccine groups, gastroenteritis and pneumonia were the most frequently reported unsolicited AE. Fever was the most frequently observed solicited AE and was recorded after 11% of RTS,S/AS01(E) doses compared to 31% of doses of rabies vaccine. The candidate vaccine RTS,S/AS01(E) showed an acceptable safety profile in children living in a malaria-endemic area in East Africa. More data on the safety of RTS,S/AS01(E) will become available from the Phase 3 programme.

Lang T. 2010. Diverse ethics of translational research in the developing world. Am J Bioeth, 10 (8), pp. 41-42. | Read more

Nzila A, Okombo J, Becker RP, Chilengi R, Lang T, Niehues T. 2010. Anticancer agents against malaria: time to revisit? Trends Parasitol, 26 (3), pp. 125-129. | Show Abstract | Read more

The emergence of artemisinin resistance could adversely impact the current strategy for malaria treatment; thus, new drugs are urgently needed. A possible approach to developing new antimalarials is to find new uses for old drugs. Some anticancer agents such as methotrexate and trimetrexate are active against malaria. However, they are commonly perceived to be toxic and thus not suitable for malaria treatment. In this opinion article, we examine how the toxicity of anticancer agents is just a matter of dose or 'only dose makes the poison', as coined in Paracelsus' law. Thus, the opportunity exists to discover new antimalarials using the anticancer pharmacopoeia.

Lang TA, White NJ, Tran HT, Farrar JJ, Day NP, Fitzpatrick R, Angus BJ, Denis E et al. 2010. Clinical research in resource-limited settings: enhancing research capacity and working together to make trials less complicated. PLoS Negl Trop Dis, 4 (6), pp. e619. | Read more

O'Meara WP, Lang T. 2009. Malaria vaccine trial endpoints - bridging the gaps between trial design, public health and the next generation of vaccines. Parasite Immunol, 31 (9), pp. 574-581. | Show Abstract | Read more

A recent working group convened by the World Health Organization recommended that time to first or only episode of clinical malaria should be used to evaluate vaccine efficacy in phase III trials. However, calculating vaccine efficacy based on this endpoint misses important aspects of malaria disease and transmission. Here, we discuss the gaps that this approach leaves in predicting the potential public health impact of a vaccine and the challenges faced by vaccine trial designers. We examine the implications of current vaccine trial design on effectiveness studies and the next generation of malaria vaccines.

Bejon P, Lusingu J, Olotu A, Leach A, Lievens M, Vekemans J, Mshamu S, Lang T et al. 2008. Efficacy of RTS,S/AS01E vaccine against malaria in children 5 to 17 months of age. N Engl J Med, 359 (24), pp. 2521-2532. | Show Abstract | Read more

BACKGROUND: Plasmodium falciparum malaria is a pressing global health problem. A previous study of the malaria vaccine RTS,S (which targets the circumsporozoite protein), given with an adjuvant system (AS02A), showed a 30% rate of protection against clinical malaria in children 1 to 4 years of age. We evaluated the efficacy of RTS,S given with a more immunogenic adjuvant system (AS01E) in children 5 to 17 months of age, a target population for vaccine licensure. METHODS: We conducted a double-blind, randomized trial of RTS,S/AS01E vaccine as compared with rabies vaccine in children in Kilifi, Kenya, and Korogwe, Tanzania. The primary end point was fever with a falciparum parasitemia density of more than 2500 parasites per microliter, and the mean duration of follow-up was 7.9 months (range, 4.5 to 10.5). RESULTS: A total of 894 children were randomly assigned to receive the RTS,S/AS01E vaccine or the control (rabies) vaccine. Among the 809 children who completed the study procedures according to the protocol, the cumulative number in whom clinical malaria developed was 32 of 402 assigned to receive RTS,S/AS01E and 66 of 407 assigned to receive the rabies vaccine; the adjusted efficacy rate for RTS,S/AS01E was 53% (95% confidence interval [CI], 28 to 69; P<0.001) on the basis of Cox regression. Overall, there were 38 episodes of clinical malaria among recipients of RTS,S/AS01E, as compared with 86 episodes among recipients of the rabies vaccine, with an adjusted rate of efficacy against all malarial episodes of 56% (95% CI, 31 to 72; P<0.001). All 894 children were included in the intention-to-treat analysis, which showed an unadjusted efficacy rate of 49% (95% CI, 26 to 65; P<0.001). There were fewer serious adverse events among recipients of RTS,S/AS01E, and this reduction was not only due to a difference in the number of admissions directly attributable to malaria. CONCLUSIONS: RTS,S/AS01E shows promise as a candidate malaria vaccine. (ClinicalTrials.gov number, NCT00380393.)

Hawkridge T, Scriba TJ, Gelderbloem S, Smit E, Tameris M, Moyo S, Lang T, Veldsman A et al. 2008. Safety and immunogenicity of a new tuberculosis vaccine, MVA85A, in healthy adults in South Africa. J Infect Dis, 198 (4), pp. 544-552. | Show Abstract | Read more

BACKGROUND: The efficacy of bacille Calmette-Guérin (BCG) may be enhanced by heterologous vaccination strategies that boost the BCG-primed immune response. One leading booster vaccine, MVA85A (where "MVA" denotes "modified vaccinia virus Ankara"), has shown promising safety and immunogenicity in human trials performed in the United Kingdom. We investigated the safety and immunogenicity of MVA85A in mycobacteria-exposed--but Mycobacterium tuberculosis-uninfected--healthy adults from a region of South Africa where TB is endemic. METHODS: Twenty-four adults were vaccinated with MVA85A. All subjects were monitored for 1 year for adverse events and for immunological assessment. RESULTS: MVA85A vaccination was well tolerated and induced potent T cell responses, as measured by interferon (IFN)-gamma enzyme-linked immunospot assay, which exceeded prevaccination responses up to 364 days after vaccination. BCG-specific CD4+ T cells boosted by MVA85A were comprised of multiple populations expressing combinations of IFN-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-2, and IL-17, as measured by polychromatic flow cytometry. IFN-gamma-expressing and polyfunctional IFN-gamma+TNF-gamma+IL-2+ CD4+ T cells were boosted during the peak BCG-specific response, which occurred 7 days after vaccination. CONCLUSION: The excellent safety profile and quantitative and qualitative immunogenicity data strongly support further trials assessing the efficacy of MVA85A as a boosting vaccine in countries where TB is endemic. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00460590.

Lang TA, Kokwaro GO. 2008. Malaria drug and vaccine trials in Africa: obstacles and opportunities. Trans R Soc Trop Med Hyg, 102 (1), pp. 7-10. | Show Abstract | Read more

There are several new treatments and vaccine technologies in clinical development for childhood malaria that have arrived in the clinical phase of evaluation during the past 5-10 years. This is a long-awaited change as until this time there had been little in the pipeline. As these products progress, evaluating them in the populations for whom they are being developed is becoming increasingly challenging. Many more capable trial sites are required and thousands of children and their parents need to be willing to take part in all the clinical trials that will be necessary if even a handful of these products make it through to obtaining a marketing approval license. Then, beyond licensure, these products will need to be assessed in more 'real-life' phase IV trials to establish whether they can truly impact the high level of mortality that malaria brings to the under-five population in Africa. Here we explore the issues that face both the trial sites and the product developers and present how this opportunity should be utilised to develop experienced African clinical researchers and facilities alongside getting these products through into public health use.

Bejon P, Mwacharo J, Kai O, Todryk S, Keating S, Lowe B, Lang T, Mwangi TW et al. 2007. The induction and persistence of T cell IFN-gamma responses after vaccination or natural exposure is suppressed by Plasmodium falciparum. J Immunol, 179 (6), pp. 4193-4201. | Show Abstract

Epidemiological observations suggest that T cell immunity may be suppressed in malaria-endemic areas. In vitro studies, animal models, and limited data in humans link immunosuppression with malaria, malnutrition, and other parasitic infections. However, there are no data to determine whether malaria-induced immunosuppression is significant in the long-term, or relative data comparing it with other factors in malaria-endemic areas, so as to measure the impact of malaria, other parasitic disease, nutritional status, age. and location on the acquisition and longevity of IFN-gamma responses in children in Kenya. We studied these factors in two cohorts of 1- to 6-year-old children in a malaria-endemic area. T cell responses were induced by vaccination in one cohort, and acquired as a result of natural exposure in a second cohort. Serial ELISPOT assays conducted over a 1-year period measured the induction and kinetics of IFN-gamma production in response to the malaria Ag thrombospondin-related adhesion protein. Induced responses in both cohorts and the longevity of response in the vaccinated cohort were fitted to potential explanatory variables. Parasitemia was prospectively associated with reduced IFN-gamma-producing T cells in both cohorts (by 15-25%), and both parasitemia and episodes of febrile malaria were associated with 19 and 31% greater attrition of T cell responses, respectively. Malaria may reduce the efficacy vaccinations such as bacillus Calmette-Guérin and investigational T cell-inducing vaccines, and may delay the acquisition of immunity following natural exposure to malaria and other pathogens.

Bejon P, Ogada E, Mwangi T, Milligan P, Lang T, Fegan G, Gilbert SC, Peshu N, Marsh K, Hill AV. 2007. Extended follow-up following a phase 2b randomized trial of the candidate malaria vaccines FP9 ME-TRAP and MVA ME-TRAP among children in Kenya. PLoS One, 2 (8), pp. e707. | Show Abstract | Read more

BACKGROUND: "FFM ME-TRAP" is sequential immunisation with two attenuated poxvirus vectors (FP9 and modified vaccinia virus Ankara) delivering the pre-erythrocytic malaria antigen ME-TRAP. Over nine months follow-up in our original study, there was no evidence that FFM ME-TRAP provided protection against malaria. The incidence of malaria was slightly higher in children who received FFM ME-TRAP, but this was not statistically significant (hazard ratio 1.5, 95% CI 1.0-2.3). Although the study was unblinded, another nine months follow-up was planned to monitor the incidence of malaria and other serious adverse events. METHODS AND FINDINGS: 405 children aged 1-6 yrs were initially randomized to vaccination with either FFM ME-TRAP or control (rabies vaccine). 380 children were still available for follow-up after the first nine months. Children were seen weekly and whenever they were unwell for nine months monitoring. The axillary temperature was measured, and blood films taken when febrile. The primary analysis was time to parasitaemia >2,500/microl. During the second nine months monitoring, 49 events met the primary endpoint (febrile malaria with parasites >2,500/microl) in the Intention To Treat (ITT) group. 23 events occurred among the 189 children in the FFM ME-TRAP group, and 26 among the 194 children in the control group. In the full 18 months of monitoring, there were 63 events in the FFM ME-TRAP group and 60 in the control group (HR = 1.2, CI 0.84-1.73, p = 0.35). There was no evidence that the HR changed over the 18 months (test for interaction between time and vaccination p = 0.11). CONCLUSIONS: Vaccination with FFM ME-TRAP was not protective against malaria in this study. Malaria incidence during 18 months of surveillance was similar in both vaccine groups. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN88335123.

Imoukhuede EB, Andrews L, Milligan P, Berthoud T, Bojang K, Nwakanma D, Ismaili J, Buckee C et al. 2007. Low-level malaria infections detected by a sensitive polymerase chain reaction assay and use of this technique in the evaluation of malaria vaccines in an endemic area. Am J Trop Med Hyg, 76 (3), pp. 486-493. | Show Abstract

The feasibility of using a sensitive polymerase chain reaction (PCR) to evaluate malaria vaccines in small group sizes was tested in 102 adult Gambian volunteers who received either the malaria vaccine regimen FP9 ME-TRAP/MVA ME-TRAP or rabies vaccine. All volunteers received the antimalarial drugs primaquine and Lapdap plus artesunate to eliminate malaria parasites. Volunteers in a further group received an additional single treatment with sulfadoxine-pyrimethamine (SP) to prevent new infections. There was substantially lower T-cell immunogenicity than in previous trials with this vaccine regimen and no protection against infection in the malaria vaccine group. Using the primary endpoint of 20 parasites per mL, no difference was found in the prevalence of low-level infections in volunteers who received SP compared with those who did not, indicating that SP did not reduce the incidence of very low-density infection. However, SP markedly reduced the incidence of higher density infections. These findings support the feasibility and potential of this approach to screen pre-erythrocytic vaccines for efficacy against infection in small numbers of vaccinees in endemic areas.

Bejon P, Ogada E, Mwangi T, Milligan P, Lang T, Fegan G, Gilbert SC, Peshu N, Marsh K, Hill AVS. 2007. Extended Follow-Up Following a Phase 2b Randomized Trial of the Candidate Malaria Vaccines FP9 ME-TRAP and MVA ME-TRAP among Children in Kenya PLOS ONE, 2 (8), | Show Abstract | Read more

BACKGROUND: "FFM ME-TRAP" is sequential immunisation with two attenuated poxvirus vectors (FP9 and modified vaccinia virus Ankara) delivering the pre-erythrocytic malaria antigen ME-TRAP. Over nine months follow-up in our original study, there was no evidence that FFM ME-TRAP provided protection against malaria. The incidence of malaria was slightly higher in children who received FFM ME-TRAP, but this was not statistically significant (hazard ratio 1.5, 95% CI 1.0-2.3). Although the study was unblinded, another nine months follow-up was planned to monitor the incidence of malaria and other serious adverse events. METHODS AND FINDINGS: 405 children aged 1-6 yrs were initially randomized to vaccination with either FFM ME-TRAP or control (rabies vaccine). 380 children were still available for follow-up after the first nine months. Children were seen weekly and whenever they were unwell for nine months monitoring. The axillary temperature was measured, and blood films taken when febrile. The primary analysis was time to parasitaemia >2,500/microl. During the second nine months monitoring, 49 events met the primary endpoint (febrile malaria with parasites >2,500/microl) in the Intention To Treat (ITT) group. 23 events occurred among the 189 children in the FFM ME-TRAP group, and 26 among the 194 children in the control group. In the full 18 months of monitoring, there were 63 events in the FFM ME-TRAP group and 60 in the control group (HR = 1.2, CI 0.84-1.73, p = 0.35). There was no evidence that the HR changed over the 18 months (test for interaction between time and vaccination p = 0.11). CONCLUSIONS: Vaccination with FFM ME-TRAP was not protective against malaria in this study. Malaria incidence during 18 months of surveillance was similar in both vaccine groups. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN88335123.

Bejon P, Keating S, Mwacharo J, Kai OK, Dunachie S, Walther M, Berthoud T, Lang T et al. 2006. Early gamma interferon and interleukin-2 responses to vaccination predict the late resting memory in malaria-naïve and malaria-exposed individuals. Infect Immun, 74 (11), pp. 6331-6338. | Show Abstract | Read more

Two different cell populations respond to potent T-cell-inducing vaccinations. The induction and loss of effector cells can be seen using an ex vivo enzyme-linked immunospot (ELISPOT) assay, but the more durable resting memory response is demonstrable by a cultured ELISPOT assay. The relationship of the early effector response to durable resting memory is incompletely understood. Effector phenotype is usually identified by gamma interferon (IFN-gamma) production, but interleukin-2 (IL-2) has been specifically linked to the differentiation of memory cells. Here, IFN-gamma- and IL-2-secreting effector cells were identified by an ex vivo ELISPOT assay 1 week after vaccination and compared with the resting memory responses detected by a cultured ELISPOT assay 3 months later. The different kinetics and induction of IL-2 by different vaccines and natural exposure are described. Furthermore, both early IFN-gamma and IL-2 production independently predicted subsequent memory responses at 3 months in malaria-naïve volunteers, but only IFN-gamma predicted memory in malaria-exposed volunteers. However, dual ELISPOT assays were also performed on malaria-exposed volunteers to identify cells producing both cytokines simultaneously. This demonstrated that double-cytokine-producing cells were highly predictive of memory. This assay may be useful in predicting vaccinations most likely to generate stable, long-term memory responses.

Imoukhuede EB, Berthoud T, Milligan P, Bojang K, Ismaili J, Keating S, Nwakanma D, Keita S et al. 2006. Safety and immunogenicity of the malaria candidate vaccines FP9 CS and MVA CS in adult Gambian men. Vaccine, 24 (42-43), pp. 6526-6533. | Show Abstract | Read more

We assessed the safety and immunogenicity of prime-boost vectors encoding the Plasmodium falciparum circumsporozoite (CS) protein expressed either in the attenuated fowl-pox virus (FP9) or modified vaccinia virus Ankara (MVA). Thirty-two adult Gambians in groups of four to eight received one, two or three doses of FP9 CS and/or MVA CS. No serious adverse event was observed following vaccination. The most immunogenic regimen was two doses of FP9 followed by a single dose of MVA 4 weeks later (an average of 1000 IFN-gamma spot forming units/million PBMCs). This level of effector T-cell responses appears higher than that seen in previously reported studies of CS-based candidate malaria vaccines.

Bejon P, Mwacharo J, Kai O, Mwangi T, Milligan P, Todryk S, Keating S, Lang T et al. 2006. A phase 2b randomised trial of the candidate malaria vaccines FP9 ME-TRAP and MVA ME-TRAP among children in Kenya. PLoS Clin Trials, 1 (6), pp. e29. | Show Abstract | Read more

OBJECTIVE: The objective was to measure the efficacy of the vaccination regimen FFM ME-TRAP in preventing episodes of clinical malaria among children in a malaria endemic area. FFM ME-TRAP is sequential immunisation with two attenuated poxvirus vectors (FP9 and modified vaccinia virus Ankara), which both deliver the pre-erythrocytic malaria antigen construct multiple epitope-thrombospondin-related adhesion protein (ME-TRAP). DESIGN: The trial was randomised and double-blinded. SETTING: The setting was a rural, malaria-endemic area of coastal Kenya. PARTICIPANTS: We vaccinated 405 healthy 1- to 6-year-old children. INTERVENTIONS: Participants were randomised to vaccination with either FFM ME-TRAP or control (rabies vaccine). OUTCOME MEASURES: Following antimalarial drug treatment children were seen weekly and whenever they were unwell during nine months of monitoring. The axillary temperature was measured, and blood films taken when febrile. The primary analysis was time to a parasitaemia of over 2,500 parasites/mul. RESULTS: The regime was moderately immunogenic, but the magnitude of T cell responses was lower than in previous studies. In intention to treat (ITT) analysis, time to first episode was shorter in the FFM ME-TRAP group. The cumulative incidence of febrile malaria was 52/190 (27%) for FFM ME-TRAP and 40/197 (20%) among controls (hazard ratio = 1.52). This was not statistically significant (95% confidence interval [CI] 1.0-2.3; p = 0.14 by log-rank). A group of 346 children were vaccinated according to protocol (ATP). Among these children, the hazard ratio was 1.3 (95% CI 0.8-2.1; p = 0.55 by log-rank). When multiple malaria episodes were included in the analyses, the incidence rate ratios were 1.6 (95% CI 1.1-2.3); p = 0.017 for ITT, and 1.4 (95% CI 0.9-2.1); p = 0.16 for ATP. Haemoglobin and parasitaemia in cross-sectional surveys at 3 and 9 mo did not differ by treatment group. Among children vaccinated with FFM ME-TRAP, there was no correlation between immunogenicity and malaria incidence. CONCLUSIONS: No protection was induced against febrile malaria by this vaccine regimen. Future field studies will require vaccinations with stronger immunogenicity in children living in malarious areas.

Bejon P, Kai OK, Mwacharo J, Keating S, Lang T, Gilbert SC, Peshu N, Marsh K, Hill AV. 2006. Alternating vector immunizations encoding pre-erythrocytic malaria antigens enhance memory responses in a malaria endemic area. Eur J Immunol, 36 (8), pp. 2264-2272. | Show Abstract | Read more

A heterologous prime-boost strategy has been developed to potently induce T cell responses to pre-erythrocytic malaria antigens. Efficacy in the field is likely to depend on both peak immunogenicity and the durability of responses. To improve both immunogenicity and durability of responses, 54 adult males from a malaria endemic area were immunized with different vaccination regimens, systematically varying antigenic insert and the number and sequence of component vaccinations. The component vaccinations were recombinant attenuated viruses, either fowlpox (FP) 9 or modified vaccinia virus Ankara (MVA). These were recombinant for either of two pre-erythrocytic malaria antigens (multiple epitope-thrombospondin-related adhesion protein, ME-TRAP, or circumsporozoite antigen (CS). ELISPOT assays were used to measure the effector and resting memory T cell responses. Sequence, antigen insert and number of vaccinations influenced immunogenicity, but the novel alternating vector immunizations generated the largest resting memory T cell populations. Effector responses were maintained at 84% of the peak response after 270 days. This durability of response is unprecedented. Classical prime-boost vaccination responses were at 5% of the peak after 270 days. Vaccines administered by heterologous prime-boost regimes are being developed for diverse pathogens and cancer. These data suggest these vaccines should also be administered by alternating vector regimens in clinical development.

Bejon P, Mwacharo J, Kai OK, Todryk S, Keating S, Lang T, Gilbert SC, Peshu N, Marsh K, Hill AV. 2006. Immunogenicity of the candidate malaria vaccines FP9 and modified vaccinia virus Ankara encoding the pre-erythrocytic antigen ME-TRAP in 1-6 year old children in a malaria endemic area. Vaccine, 24 (22), pp. 4709-4715. | Show Abstract | Read more

In a phase 1 trial, 22 children in a malaria endemic area were immunised with candidate malaria vaccination regimes. The regimes used two recombinant viral vectors, attenuated fowlpox strain FP9 and modified vaccinia virus Ankara (MVA). Both encoded the pre-erythrocytic malaria antigen construct ME-TRAP. Strong T cell responses were detected by both ex vivo and cultured ELISpot assays. Data from phase 1 trials in adults on anti-vector responses raised by FP9 is presented. These responses partially cross-reacted with MVA, and detectably reduced the immunogenicity of vaccination with MVA. This prompted the comparison of half dose and full dose FP9 priming vaccinations in children. Regimes using half dose FP9 priming tended to be more immunogenic than full dose. The potential for enhanced immunogenicity with half doses of priming vectors warrants further investigation, and larger studies to determine protection against malaria in children are required.

Bejon P, Peshu N, Gilbert SC, Lowe BS, Molyneux CS, Forsdyke J, Lang T, Hill AV, Marsh K. 2006. Safety profile of the viral vectors of attenuated fowlpox strain FP9 and modified vaccinia virus Ankara recombinant for either of 2 preerythrocytic malaria antigens, ME-TRAP or the circumsporozoite protein, in children and adults in Kenya. Clin Infect Dis, 42 (8), pp. 1102-1110. | Show Abstract | Read more

BACKGROUND: We are developing a heterologous prime-boost vaccine strategy against malaria. This approach uses sequential immunization with different vectors to deliver a common preerythrocytic malaria antigen. Preliminary evidence of efficacy and safety has been previously documented in studies from an area where malaria is nonendemic. Additional safety data from an area where malaria is endemic are now required before larger-scale studies are undertaken to determine the efficacy of this vaccine strategy in the field. Other modified vaccinia virus Ankara (MVA) recombinants and prime-boost immunizations are being developed as vaccines against human immunodeficiency virus (HIV) infection, tuberculosis, and cancer, and MVA is a candidate attenuated smallpox vaccine. METHODS: Candidate vaccines against malaria were intradermally administered to 73 adults (7 of whom were HIV positive) and 22 children in Kenya. These vaccines used the attenuated fowlpox strain FP9 and the MVA recombinant for either of 2 preerythrocytic malaria antigens, multiple preerythrocytic-stage epitopes joined with the preerythrocytic-stage antigen TRAP (ME-TRAP) and the circumsporozoite protein (CS). Adverse events were recorded. RESULTS: Reactogenicity was mild. MVA caused less frequent and less severe cutaneous reaction if given after FP9 priming. Half doses reduced the frequency and the severity of systemic reactogenicity, and particular vaccine lots were associated with different reactogenicities. Unexpectedly, prior immunity to the ME-TRAP antigen appeared to be protective against local reactions after immunization. CONCLUSIONS: Where the final intention is to use MVA after FP9 priming, previous testing of MVA alone overestimates reactogenicity. These recombinant vectors appear to be safe and suitable for use in larger-scale studies of children in Africa and of HIV-positive individuals.

Lang T, Hughes D, Kanyok T, Kengeya-Kayondo J, Marsh V, Haaland A, Pirmohamed M, Winstanley P. 2006. Beyond registration--measuring the public-health potential of new treatments for malaria in Africa. Lancet Infect Dis, 6 (1), pp. 46-52. | Show Abstract | Read more

Malaria claims over one million lives a year in some of the poorest countries of the world. Affected populations and governments cannot afford to pay for expensive new therapies. Most antimalarial treatments are purchased from local shops and administered in the home. These factors make for a complex set of requirements for any new treatment for malaria if a substantial reduction in mortality is ever to be achieved. Thankfully there are several treatments being developed, mostly within public-private partnerships. Typically, the goal of public-private partnerships is the granting of a product license, so work plans end after phase III trials. As these drugs will ultimately be used unsupervised, malaria control programme managers will require further data on safety and whether the drug is as efficacious when used outside of controlled clinical trials before allowing widespread use of these new products. These data need to be collected in highly specific phase IV programmes. We explain why public-private partnerships should extend their development plans well beyond drug registration, and set out the requirements of such a programme. We aim to generate debate and discussion so that guidelines that are internationally accepted and adhered to can be developed not only for antimalarials but for all drugs that are being developed specifically for use in resource-poor settings.

Lang T, Hill AV, McShane H, Shah R, Towse A, Pritchard C, Garau M. 2005. New TB vaccine granted orphan drug status. BMJ, 331 (7530), pp. 1476. | Read more

Lang T, Hill A. 2005. Developing a deployable vaccine for Africa [MIM-TL-0] ACTA TROPICA, 95 pp. S311-S311.

Bejon P, Mwacharo J, Kai O, Lowe B, Todryk S, Peshu N, Gilbert S, Lang T, Marsh K, Hill A. 2005. Safety, immunogenicity and efficacy studies of candidate malaria vaccines FP9 and MVA encoding ME-TRAP in Kenyan children [MIM-PB-224908] ACTA TROPICA, 95 pp. S84-S84.

Treweek S, Altman DG, Bower P, Campbell M, Chalmers I, Cotton S, Craig P, Crosby D et al. 2015. Making randomised trials more efficient: report of the first meeting to discuss the Trial Forge platform. Trials, 16 (1), pp. 261. | Show Abstract | Read more

Randomised trials are at the heart of evidence-based healthcare, but the methods and infrastructure for conducting these sometimes complex studies are largely evidence free. Trial Forge ( www.trialforge.org ) is an initiative that aims to increase the evidence base for trial decision making and, in doing so, to improve trial efficiency.This paper summarises a one-day workshop held in Edinburgh on 10 July 2014 to discuss Trial Forge and how to advance this initiative. We first outline the problem of inefficiency in randomised trials and go on to describe Trial Forge. We present participants' views on the processes in the life of a randomised trial that should be covered by Trial Forge.General support existed at the workshop for the Trial Forge approach to increase the evidence base for making randomised trial decisions and for improving trial efficiency. Agreed upon key processes included choosing the right research question; logistical planning for delivery, training of staff, recruitment, and retention; data management and dissemination; and close down. The process of linking to existing initiatives where possible was considered crucial. Trial Forge will not be a guideline or a checklist but a 'go to' website for research on randomised trials methods, with a linked programme of applied methodology research, coupled to an effective evidence-dissemination process. Moreover, it will support an informal network of interested trialists who meet virtually (online) and occasionally in person to build capacity and knowledge in the design and conduct of efficient randomised trials.Some of the resources invested in randomised trials are wasted because of limited evidence upon which to base many aspects of design, conduct, analysis, and reporting of clinical trials. Trial Forge will help to address this lack of evidence.

Cooper BS, Boni MF, Pan-ngum W, Day NP, Horby PW, Olliaro P, Lang T, White NJ, White LJ, Whitehead J. 2015. Evaluating clinical trial designs for investigational treatments of Ebola virus disease. PLoS Med, 12 (4), pp. e1001815. | Show Abstract | Read more

BACKGROUND: Experimental treatments for Ebola virus disease (EVD) might reduce EVD mortality. There is uncertainty about the ability of different clinical trial designs to identify effective treatments, and about the feasibility of implementing individually randomised controlled trials during an Ebola epidemic. METHODS AND FINDINGS: A treatment evaluation programme for use in EVD was devised using a multi-stage approach (MSA) with two or three stages, including both non-randomised and randomised elements. The probabilities of rightly or wrongly recommending the experimental treatment, the required sample size, and the consequences for epidemic outcomes over 100 d under two epidemic scenarios were compared for the MSA, a sequential randomised controlled trial (SRCT) with up to 20 interim analyses, and, as a reference case, a conventional randomised controlled trial (RCT) without interim analyses. Assuming 50% 14-d survival in the population treated with the current standard of supportive care, all designs had similar probabilities of identifying effective treatments correctly, while the MSA was less likely to recommend treatments that were ineffective. The MSA led to a smaller number of cases receiving ineffective treatments and faster roll-out of highly effective treatments. For less effective treatments, the MSA had a high probability of including an RCT component, leading to a somewhat longer time to roll-out or rejection. Assuming 100 new EVD cases per day, the MSA led to between 6% and 15% greater reductions in epidemic mortality over the first 100 d for highly effective treatments compared to the SRCT. Both the MSA and SRCT led to substantially fewer deaths than a conventional RCT if the tested interventions were either highly effective or harmful. In the proposed MSA, the major threat to the validity of the results of the non-randomised components is that referral patterns, standard of care, or the virus itself may change during the study period in ways that affect mortality. Adverse events are also harder to quantify without a concurrent control group. CONCLUSIONS: The MSA discards ineffective treatments quickly, while reliably providing evidence concerning effective treatments. The MSA is appropriate for the clinical evaluation of EVD treatments.

Negussie H, Kassahun MM, Fegan G, Njuguna P, Enquselassie F, McKay A, Newport M, Lang T, Davey G. 2015. Podoconiosis treatment in northern Ethiopia (GoLBet): study protocol for a randomised controlled trial. Trials, 16 (1), pp. 307. | Show Abstract | Read more

BACKGROUND: Podoconiosis is one of the forgotten types of leg swelling (elephantiasis) in the tropics. Unlike the other, better-known types of leg swelling, podoconiosis is not caused by any parasite, virus or bacterium, but by an abnormal reaction to minerals found in the clay soils of some tropical highland areas. Non-governmental Organizations (NGOs) have been responsible for the development of simple treatment methods without systematic evaluation of its effectiveness. It is essential that a large scale, fully controlled, pragmatic trial of the intervention is conducted. We aim to test the hypothesis that community-based treatment of podoconiosis lymphoedema reduces the frequency of acute dermatolymphangioadenitis episodes ('acute attacks') and improves other clinical, social and economic outcomes. METHODS/DESIGN: This is a pragmatic, individually randomised controlled trial. We plan to randomly allocate 680 podoconiosis patients from the East Gojjam Zone in northern Ethiopia to one of two groups: 'Standard Treatment' or 'Delayed Treatment'. Those randomised to standard treatment will receive the hygiene and foot-care intervention from May 2015 for one year, whereas those in the control arm will be followed through 2015 and be offered the intervention in 2016. The trial will be preceded by an economic context survey and a Rapid Ethical Assessment to identify optimal methods of conveying information about the trial and the approaches to obtaining informed consent preferred by the community. The primary outcome will be measured by recording patient recall and using a simple, patient-held diary that will be developed to record episodes of acute attacks. Adherence to treatment, clinical stage of disease, quality of life, disability and stigma will be considered secondary outcome measures. Other outcomes will include adverse events and economic productivity. Assessments will be made at baseline and at 3, 6, 9 and 12 months thereafter. DISCUSSION: The evidence is highly likely to inform implementation of the new master plan for integrated control of Neglected Tropical Diseases (NTDs), in which podoconiosis is identified as one of eight NTDs prioritised for control. Potentially, an estimated 3 million patients in Ethiopia will therefore benefit from the results of this trial. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number. REGISTRATION NUMBER: ISRCTN67805210. Date of registration: 24 January 2013.

Furtado T, Franzen S, van Loggerenberg F, Carn G, Grahek S, McBride M, Power M, O'Reilly J et al. 2014. Strengthening neglected tropical disease research through enhancing research-site capacity: an evaluation of a novel web application to facilitate research collaborations. PLoS Negl Trop Dis, 8 (11), pp. e3225. | Read more

Chantler T, Cheah PY, Miiro G, Hantrakum V, Nanvubya A, Ayuo E, Kivaya E, Kidola J et al. 2014. International health research monitoring: exploring a scientific and a cooperative approach using participatory action research. BMJ Open, 4 (2), pp. e004104. | Show Abstract | Read more

OBJECTIVES: To evaluate and determine the value of monitoring models developed by the Mahidol Oxford Tropical Research Unit and the East African Consortium for Clinical Research, consider how this can be measured and explore monitors' and investigators' experiences of and views about the nature, purpose and practice of monitoring. RESEARCH DESIGN: A case study approach was used within the context of participatory action research because one of the aims was to guide and improve practice. 34 interviews, five focus groups and observations of monitoring practice were conducted. SETTING AND PARTICIPANTS: Fieldwork occurred in the places where the monitoring models are coordinated and applied in Thailand, Cambodia, Uganda and Kenya. Participants included those coordinating the monitoring schemes, monitors, senior investigators and research staff. ANALYSIS: Transcribed textual data from field notes, interviews and focus groups was imported into a qualitative data software program (NVIVO V. 10) and analysed inductively and thematically by a qualitative researcher. The initial coding framework was reviewed internally and two main categories emerged from the subsequent interrogation of the data. RESULTS: The categories that were identified related to the conceptual framing and nature of monitoring, and the practice of monitoring, including relational factors. Particular emphasis was given to the value of a scientific and cooperative style of monitoring as a means of enhancing data quality, trust and transparency. In terms of practice the primary purpose of monitoring was defined as improving the conduct of health research and increasing the capacity of researchers and trial sites. CONCLUSIONS: The models studied utilise internal and network wide expertise to improve the ethics and quality of clinical research. They demonstrate how monitoring can be a scientific and constructive exercise rather than a threatening process. The value of cooperative relations needs to be given more emphasis in monitoring activities, which seek to ensure that research protects human rights and produces reliable data.

Lang T, Marsh K, Peeling R, Farrar J. 2013. Sharing methods for global health research: an assessment of methodology LANCET, 382 pp. 5-5.

Franzen SRP, Chandler C, Atashili J, Angus B, Lang T. 2013. Barriers and enablers of locally led clinical trials in Ethiopia and Cameroon: a prospective, qualitative study LANCET, 382 pp. 14-14.

Franzen SR, Chandler C, Enquselassie F, Siribaddana S, Atashili J, Angus B, Lang T. 2013. Understanding the investigators: a qualitative study investigating the barriers and enablers to the implementation of local investigator-initiated clinical trials in Ethiopia. BMJ Open, 3 (11), pp. e003616. | Show Abstract | Read more

OBJECTIVES: Clinical trials provide 'gold standard' evidence for policy, but insufficient locally relevant trials are conducted in low-income and middle-income countries. Local investigator-initiated trials could generate highly relevant data for national governments, but information is lacking on how to facilitate them. We aimed to identify barriers and enablers to investigator-initiated trials in Ethiopia to inform and direct capacity strengthening initiatives. DESIGN: Exploratory, qualitative study comprising of in-depth interviews (n=7) and focus group discussions (n=3). SETTING: Fieldwork took place in Ethiopia during March 2011. PARTICIPANTS: Local health researchers with previous experiences of clinical trials or stakeholders with an interest in trials were recruited through snowball sampling (n=20). OUTCOME MEASURES: Detailed discussion notes were analysed using thematic coding analysis and key themes were identified. RESULTS: All participants perceived investigator-initiated trials as important for generating local evidence. System and organisational barriers included: limited funding allocation, weak regulatory and administrative systems, few learning opportunities, limited human and material capacity and poor incentives for conducting research. Operational hurdles were symptomatic of these barriers. Lack of awareness, confidence and motivation to undertake trials were important individual barriers. Training, knowledge sharing and experience exchange were key enablers to trial conduct and collaboration was unanimously regarded as important for improving capacity. CONCLUSIONS: Barriers to trial conduct were found at individual, operational, organisational and system levels. These findings indicate that to increase locally led trial conduct in Ethiopia, system wide changes are needed to create a more receptive and enabling research environment. Crucially, the creation of research networks between potential trial groups could provide much needed practical collaborative support through sharing of financial and project management burdens, knowledge and resources. These findings could have important implications for capacity-strengthening initiatives but further research is needed before the results can be generalised more widely.

Lang T, Siribaddana S. 2012. Clinical trials have gone global: is this a good thing? PLoS Med, 9 (6), pp. e1001228. | Read more

Lang T. 2012. Using digital technology to support and enhance clinical trials in resource-limited settings TROPICAL MEDICINE & INTERNATIONAL HEALTH, 17 pp. 49-49.

Lang T. 2011. Adaptive trial design: could we use this approach to improve clinical trials in the field of global health? Am J Trop Med Hyg, 85 (6), pp. 967-970. | Show Abstract | Read more

We need more clinical trials in the world's poorest regions to evaluate new drugs and vaccines, and also to find better ways to manage health issues. Clinical trials are expensive, time consuming, and cumbersome. However, in wealthier regions these limiting factors are being addressed to make trials less administrative and improve the designs. A good example is adaptive trial design. This innovation is becoming accepted by the regulators and has been taken up by the pharmaceutical industry to reduce product development times and costs. If this approach makes trials easier and less expensive surely we should be implementing this approach in the field of tropical medicine and international health? As yet this has rarely been proposed and there are few examples. There is a need for raising the awareness of these design approaches because they could be used to make dramatic improvements to clinical research in developing countries.

Boga M, Davies A, Kamuya D, Kinyanjui SM, Kivaya E, Kombe F, Lang T, Marsh V et al. 2011. Strengthening the informed consent process in international health research through community engagement: The KEMRI-Wellcome Trust Research Programme Experience. PLoS Med, 8 (9), pp. e1001089. | Read more

The potential for developing pragmatic clinical trials that require ‘point of care’ randomisation within routine settings in low-income settings.

Typical randomised controlled trials (RCT) focus on internal validity and efficacy, often focusing on highly selected patient populations that represent distinct subgroups of the large mix of patients who present to routine services. They also operate through parallel, tightly regulated systems that can make them expensive and time consuming. They often do not therefore identify which interventions work for which patient populations and they do not address questions of feasibility or optimal ...

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