Sustainability, affordability, and equity of corporate drug donations: the case of Malarone

Clinical development of new prophylactic antimalarial drugs after the 5th Amendment to the Declaration of Helsinki

Malaria is of continuing concern in nonimmune traveling populations. Traditionally, antimalarial drugs have been developed as agents for dual indications (treatment and prophylaxis). However, since 2000, when the 5th Amendment to the Declaration of Helsinki (DH2000) was adopted, development of new malaria prophylaxis drugs in this manner has ceased. As a consequence, there may not be any new drugs licensed for this indication in the foreseeable future. Major pharmaceutical companies have interpreted DH2000 to mean that the traditional development paradigm may be considered unethical because of doubt over the likelihood of benefit to endemic populations participating in clinical studies, the use of placebo, and the sustainability of post-trial access to study medications. In this article, we explore the basis of these concerns and suggest that the traditional development paradigm remains ethical under certain circumstances. We also consider alternative approaches that may be more attractive to sponsors as they either do not use placebo, or utilize populations in endemic countries who may unambiguously benefit. These approaches represent the way forward in the future, but are at present unproven in clinical practice, and face numerous regulatory, logistical and technical challenges. Consequently, in the short term, we argue that the traditional clinical development paradigm remains the most feasible approach and is ethical and consistent with the spirit of DH2000 under the appropriate circumstances.

To give is better than to receive: compliance with WHO guidelines for drug donations during 2000-2008

OBJECTIVE

to assess drug donations in terms of their adherence to the drug donation guidelines put forth by the World Health Organization (WHO).

METHODS

in 2009 we searched the academic and lay literature - journal articles, media articles and industry and donor web sites - to identify reports about drug donations made from 2000 to 2008. Publications focusing on molecular mechanisms of drug action, general descriptions of guidelines or specific one-time drug donations before 2000 were excluded. For cases with sufficient information, we assessed compliance with each of the 12 articles of WHO's guidelines.

FINDINGS

we found 95 articles describing 96 incidents of drug donations between 2000 and 2008. Of these, 50 were made in response to disaster situations, 43 involved the long-term donation of a drug to treat a specific disease and 3 were drug recycling cases. Disaster-related donations were less likely to comply with the guidelines, particularly in terms of meeting the recipient's needs, quality assurance and shelf-life, packaging and labelling, and information management. Recipient countries were burdened with the costs of destroying the drugs received through inappropriate donations. Although long-term donations were more likely to comply with WHO guidelines related to quality assurance and labelling, they did not consistently meet the needs of the recipients. Furthermore, they discouraged local drug production and development.

CONCLUSION

drug donations can do more harm than good for the recipient countries. Strengthening the structures and systems for coordinating and monitoring drug donations and ensuring that these are driven by recipient needs will improve adherence to the drug donation guidelines set forth by WHO.

Molecular surveillance of mutations in the cytochrome b gene of Plasmodium falciparum in Gabon and Ethiopia

Background

Atovaquone is part of the antimalarial drug combination atovaquone-proguanil (Malarone^®) and inhibits the cytochrome bc₁ complex of the electron transport chain in Plasmodium spp. Molecular modelling showed that amino acid mutations are clustered around a putative atovaquone-binding site resulting in a reduced binding affinity of atovaquone for plasmodial cytochrome b, thus resulting in drug resistance.

Methods

The prevalence of cytochrome b point mutations possibly conferring atovaquone resistance in Plasmodium falciparum isolates in atovaquone treatment-naïve patient cohorts from Lambaréné, Gabon and from South Western Ethiopia was assessed.

Results

Four/40 (10%) mutant types (four different single polymorphisms, one leading to an amino acid change from M to I in a single case) in Gabonese isolates, but all 141/141 isolates were wild type in Ethiopia were found.

Conclusion

In the absence of drug pressure, spontaneous and possibly resistance-conferring mutations are rare.

Antimalarial drugs - host targets (re)visited

Every year, forty percent of the world population is at risk of contracting malaria. Hopes for the erradication of this disease during the 20th century were dashed by the ability of Plasmodium falciparum, its most deadly causative agent, to develop resistance to available drugs. Efforts to produce an effective vaccine have so far been unsuccessful, enhancing the need to develop novel antimalarial drugs. In this review, we summarize our knowledge concerning existing antimalarials, mechanisms of drug-resistance development, the use of drug combination strategies and the quest for novel anti-plasmodial compounds. We emphasize the potential role of host genes and molecules as novel targets for newly developed drugs. Recent results from our laboratory have shown Hepatocyte Growth Factor/MET signaling to be essential for the establishment of infection in hepatocytes. We discuss the potential use of this pathway in the prophylaxis of malaria infection.

Atovaquone-proguanil for treating uncomplicated malaria

BACKGROUND

Many conventional treatments for uncomplicated malaria are failing because malaria parasites develop resistance to them. One way to combat this resistance is to treat people with a combination of drugs, such as atovaquone-proguanil.

OBJECTIVES

To compare atovaquone-proguanil with other antimalarial drugs (alone or in combination) for treating children and adults with uncomplicated Plasmodium falciparum malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (June 2005), CENTRAL (The Cochrane Library Issue 2, 2005), MEDLINE (1966 to June 2005), EMBASE (1980 to June 2005), LILACS (1982 to June 2005), reference lists, and conference abstracts. We also contacted relevant pharmaceutical manufacturers and researchers.

SELECTION CRITERIA

Randomized controlled trials comparing atovaquone-proguanil with other antimalarial drugs for treating children and adults confirmed to have uncomplicated P. falciparum malaria.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed trial eligibility and methodological quality, and extracted data for an intention-to-treat analysis (where possible). We used relative risk (RR) and 95% confidence intervals (CI) for dichotomous data. We contacted trial authors for additional information where needed.

MAIN RESULTS

Ten trials, with a total of 2345 participants, met the inclusion criteria. The trials were conducted in four geographical regions and were often small, but they included comparisons across eight drugs. Nine trials were funded by a pharmaceutical company, only three carried out an intention-to-treat analysis, and allocation concealment was unclear in seven. Atovaquone-proguanil had fewer treatment failures by day 28 than chloroquine (RR 0.04, 95% CI 0.00 to 0.57; 27 participants, 1 trial), amodiaquine (RR 0.22, 95% CI 0.13 to 0.36; 342 participants, 2 trials), and mefloquine (RR 0.04, 95% CI 0.00 to 0.73; 158 participants, 1 trial). There were insufficient data to draw a conclusion for this outcome from comparisons with sulfadoxine-pyrimethamine (172 participants, 2 trials), halofantrine (205 participants, 1 trial), artesunate plus mefloquine (1063 participants, 1 trial), quinine plus tetracycline (154 participants, 1 trial), and dihydroartemisinin-piperaquine-trimethoprim-primaquine (161 participants, 1 trial). Adverse events were mainly common symptoms of malaria and did not differ in frequency between groups.

AUTHORS' CONCLUSIONS

Data are limited but appear to suggest that atovaquone-proguanil is more effective than chloroquine, amodiaquine, and mefloquine. There are insufficient data for comparisons against sulfadoxine-pyrimethamine, halofantrine, artesunate plus mefloquine, quinine plus tetracycline, and dihydroartemisinin-piperaquine-trimethoprim-primaquine in treating malaria. There are not enough data to assess safety, but a number of adverse events were identified with all drugs. Large trials comparing atovaquone-proguanil with other new combination therapies are needed.

Therapy of falciparum malaria in sub-saharan Africa: from molecule to policy

The burden of falciparum malaria remains as great as ever, and, as has probably always been the case, it is carried mainly by tropical Africa. Of the various means available for the control of malaria, the use of effective drugs remains the most important and is likely to remain so for a considerable time to come. Unfortunately, the extensive development of resistance by the parasite threatens the utility of most of the affordable classes of drug: the development of novel antimalarials has never been more urgently needed. Any attempt to understand the vast complexities of falciparum malaria in Africa requires an ability to think "from molecule to policy." In consequence, the review ambitiously tries to examine the current pharmacopeia, the process by which new drugs are developed and the ways in which drugs are actually used, in both the formal and informal health sectors. The informal sector is particularly important in Africa, where around half of all antimalarial treatments are bought from informal outlets and taken at home without supervision by health care professionals: the potential impact of adherence on clinical outcome is discussed. Given that the full costs are carried by the patient in a large proportion of cases, the importance of drug affordability is explored. The review also discusses the splicing of new drugs into national policy. The various parameters that feed into deliberations on changes in drug policy are discussed.

The World Health Organization and the Pharmaceutical Industry. Common areas of interest and differing views

No article published in the scientific press in the last 10 years reviews the various areas of interest common to the World Health Organization (WHO) and the pharmaceutical industry. Despite a vast amount of information in the public domain, the policies expound the views only of the bodies they represent rather than comparing differing views. An understanding of the factors which affect the interaction between these organisations as well as the organisational structures and the actual areas of intersecting interest, may help to find ways for the industry to assist the WHO in its endeavours in developing countries. Modern drug development is performed initially in and for western society, leaving the areas of infectious or tropical diseases with relatively less industry investment than cancer and cardiovascular disorders. Aspects of the development of an ethical drug, regardless of its therapeutic class (selection of drug name, intellectual property rights, drug safety, marketing and pricing, quality assurance and counterfeiting, generic use, emerging drug donations) are influenced to varying degrees by the triad of money, politics and medical need and the perspectives (each defensible) placed thereon by the WHO and industry. Instead of simply defending their positions combining the best of these strategies to optimise drug development for the needs of developing countries appears logical. Similarly, via its philanthropic initiatives, industry will have donated over $US1 billion in drug and research aid in the period 1995 to 2005. These charitable projects should yield useful information for planning and organising future aid efforts. Global warming, only recently given serious governmental consideration, is an area not yet addressed in drug development policy although along with geographical effects, it is likely to have an impact on the epidemiology of diseases e.g. malaria returning to the Mediterranean, worldwide. With changing disease patterns (and particularly if the western world is affected directly), a shift in emphasis on future medical needs and drug development can be anticipated. Furthermore, given the increased modern interest in herbal medicines and the fact that poorer countries rely heavily on traditional medicines, archiving of botanicals under threat would preserve plants for future medicinal testing or use. Coupled with the environmental and poverty issues that the WHO already attempts to address in developing countries, it is timely for both bodies to work towards certain agreed mutual aims. To work effectively, it is realistic that both bodies must benefit and also make concessions in this interactive process.

Malarone treatment failure and in vitro confirmation of resistance of Plasmodium falciparum isolate from Lagos, Nigeria

We report the first in vitro and genetic confirmation of Malarone (GlaxoSmithKline; atovaquone and proguanil hydrochloride) resistance in Plasmodium falciparum acquired in Africa. On presenting with malaria two weeks after returning from a 4-week visit to Lagos, Nigeria without prophylaxis, a male patient was given a standard 3-day treatment course of Malarone. Twenty-eight days later the parasitaemia recrudesced. Parasites were cultured from the blood and the isolate (NGATV01) was shown to be resistant to atovaquone and the antifolate pyrimethamine. The cytochrome b gene of isolate NGATV01 showed a single mutation, Tyr268Asn which has not been seen previously.