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SLEEPING SICKNESS Human African (HAT) Major progress seen, punctuated by fi rst improved treatment for stage 2 sleeping sickness in 25 years

PRIORITY TARGET PRODUCT PROFILE FOR HAT • A new treatment for stage 2 HAT in adults and children – Preferably useful for stages 1 and 2 – Active against brucei (T. b.) gambiense and T. b. rhodesiense • Better safety profi le than existing drugs – Ideally requiring little or no monitoring • Equal or better e„ cacy profi le than existing drugs – Ideally ≥ 95% clinical e cacy at 18 months after treatment • Easy-to-use treatment t the forefront of DNDi’s efforts to underreporting. Due to the resource-poor – Short course (ideally ≤ 7 days, up A develop new treatments is the need areas where the disease occurs, control to 14 days is acceptable) to understand the realities and treatment efforts are often mobilised into vertical – Preferably oral; if injectable, needs of patients and health care staff in programmes. Consisting of a series of intramuscular preferred the fi eld. specifi cally equipped and trained diagnosis – Preferably once-a-day treatment The ultimate goal for human African and treatment centres and mobile teams in • A† ordable trypanosomiasis (HAT) is a truly simplifi ed endemic areas, but these programmes are • Stable in tropical climate treatment which can be orally adminis- not integrated into regional health centres. (minimum 2-year shelf life) tered, implemented at the primary health There is an immediate need to improve – Preferably 3-year shelf life care level, and effective against both stag- current treatment options, particularly for es of the disease. Currently, both diagnosis patients with advanced stage of the disease and treatment require a complicated series where the few drugs that are available are programmes, DNDi has conducted proac- of tests and trained medical supervision. either toxic, and increasingly ineffective in tive compound mining activities to identify A key issue with HAT is that it affects hard- killing the parasite, or diffi cult to use. Ide- existing compounds with potential against to-access communities in regions with ally, a treatment will be safe enough to be kinetoplastid diseases. The compound poor health infrastructure. Poor access used in the fi rst stage of the disease and mining activities of DNDi have led to the to medical facilities, a lack of resources effective enough in the second stage of the revival of the nitromidazole class as po- and skills, and misdiagnosis contribute to disease. In addition to lead optimisation tential drug candidates: the most notable... Best science for the most neglected For more info, please contact: DNDi 15 Chemin Louis Dunant 1202 Geneva – Switzerland Tel. +4122906 9230 – Fax: +41229069231 [email protected] – www.dndi.org

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̈ HAT R&D Projects - 2010 Outlook

Discovery Preclinical Clinical Available to Patients S LS LO

Compound backup NECT mining - Chemical HAT LO Co-Administration classes Consortium Stage 2 HAT • Scynexis Oxaborole Target-based • Pace Univ Phenotypic DNDi DNDi Others DD@D

IV CPD-0801 3-day CPDD Stage 2 HAT Stage 1 HAT (TDR) ... example is fexinidazole, upon which DNDi DISCOVERY This phase requires a close, highly inter- has begun clinical development for HAT. active collaboration between the biologists Several groups worldwide have specifi c es- LEAD OPTIMISATION and chemists, who form a feedback loop: tablished expertise and knowledge in drug CONSORTIUM the biologists test the biological proper- discovery that are readily applicable to the • Partners: Scynexis, USA; Pace Univer- ties of compounds on biological systems discovery of new antitrypanosomal drugs. sity, USA while the chemists perfect the chemical In this context, DNDi has established: • DNDi project manager and coordinator: structure of these compounds based on ■ Partnerships with pharmaceutical / bio- Robert Don, Ivan Scandale information obtained by the biologists. Two technology / academic groups for interac- • Project start: April 2007 compound series have been chosen as tion and access to natural product as well lead series: as synthetic chemical libraries, chemistry, With an objective to develop optimised ■ Oxaboroles, provided by Anacor and pos- HTS, biological models, and drug design. leads by progressing ‘hit’ molecules with sessing a unique boron-based chemistry, ■ A network of key international laborato- a good safety profi le and activity against were identifi ed as hits against T. brucei ries to support discovery efforts with phar- T. brucei parasites, these consortia bring together expertise in chemistry, biology, at the Sandler Centre of the University of

DND i Drugs for Neglected Diseases initiative macokinetic, pharmacodynamic, and toxi- California San Francisco, and have shown cological expertise, and defi ned synergy screening, and pre-formulation. Optimi- in vivo activity. between these laboratories. sation focuses on the molecule’s capac- During the course of the last 15 months, At the clinical stage of development, DNDi is ity to be absorbed into the bloodstream, chemists at Scynexis have synthesized ap- working to both investigate new medicines be distributed effectively to the infection, proximately 400 compounds and screened and to also strengthen capacity for clinical survive in the body, kill the parasite and research on HAT. With the recent inclusion not harm the patient. With two full lead an additional 330 compounds from the of NECT onto the WHO Essential Medi- optimisation teams in place (a total of 18 Anacor libraries. Some compounds and in cines List, DNDi is well on its way to meet- scientists), a number of hits identifi ed from particular, SCYX 6759 cured murine cen- ing its short-term objective to bring a new, DNDi screening partners are undergoing tral nervous system infection but appeared shortcourse, co-administration treatment hit expansion. Scientists within the consor- to be actively transported from the brain. for stage 2 HAT to the patients. Through tia use advanced techniques to study how Compounds which are not effl uxed from the this project, DNDi has also built important the selected molecules interact with the brain have been synthesised. One of these relationships with other groups involved in therapeutic target (ie. a protein or an en- compounds such as SCYX-7158 is expected HAT clinical research as well as with the zyme) and optimise the drug-like charac- to become a preclinical candidate in 2010. WHO, national HAT control programmes teristics of these molecules to ensure that ■ Kinase inhibitors, of which approximately and NGOs working to control HAT. they comply with the target product profi le. 300 analogs have been synthesized to date. Signifi cant in vitro and in vivo potency has ̈ Sample compound structure of oxaboroles and kinase inhibitors been developed across the series. However no activity is expected in the second stage Oxaboroles of the disease and the series has been abandoned. To replace kinase inhibitors hit to lead pro- gram has been restarted at Scynexis and another optimized lead is expected to be Kinase inhibitors Ongoing delivered in 2011. collaboration This strategy and the promising early results with Dundee were presented during the 2008 meeting of American Society of Medicine & Tropical Thiazoles University Pyrimidines Hygiene, and are available at www.dndi.org.

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CLINICAL NIFURTIMOX’EFLORNITTHINE FEXINIZADOLE COMBINATION THERAPY “NECT” • Stage: Phase I clinical development • Major Partners: sanofi -aventis, France; Swiss Tropical Institute, Switzerland; HAT Platform partners Now available and added to the • DNDi Project Manager: Olaf Valverde Mordt WHO Essential Medicines List • DNDi Project Coordinator: Séverine Blesson as treatment against stage 2 • Project start: February 2007 sleeping sickness Fexinidazole as a drug candidate for stage 2 HAT is the fi rst success of the proactive compound mining efforts DNDi has pur- • Stage: available (fi eld studies e cacious as efl ornithine. At the end sued in particular in the ongoing) of 2008, the fi nal e cacy and safety project. • Major Partners: Epicentre, France; results of the Phase III study were A 5-nitroimidazole that was in preclinical Médecins Sans Frontières (MSF); the available and led to DNDi ’s submission development as a broad-spectrum anti- HAT National Control Programmes of of NECT for inclusion on the WHO protozoal by Hoechst in the early 1980s, the Democratic Republic of the Congo Essential Medicines List (EML). The fi nal fexinidazole was rediscovered by DNDi and the Republic of Congo; the Swiss results were published in The Lancet1 after being an abandoned compound. Ex- Tropical Institute (STI); HAT platform and were presented by Epicentre tensive profi ling by DNDi has shown that • DNDi project manager: during the 2008 meetings of American fexinidazole is orally active, crosses to the Olaf Valverde Mordt Society of Medicine & Tropical Hygiene and the HAT Platform, and are brain and has cured in vivo models for both • Project start: April 2004 and chronic infection with African available at www.dndi.org. The EML The DNDi project has shown that trypanosomes. Importantly, fexinidazole is application and support statements the use of the nifurtimox-efl ornithine of the HAT community are available not mutagenic in a panel of in vitro and in combination therapy (NECT) is on the website of the WHO Essential vivo mammalian genetic toxicology tests, as e› ective and safe as standard Medicines List. confi rming its favorable activity/toxicity efl ornithine monotherapy, but easier In May 2009, MSF, Epicentre, and profi le as a drug candidate. to use, and safer than DNDi announced that NECT had In 2007, a full preclinical programme (toxic though still widely used in 50% been included on the EML. According was established to enable fi rst-in-human of patients with stage 2 HAT). NECT is to the WHO, NECT can now be studies. the fi rst new treatment developed for used in patients and will provide This included process chemistry and GMP- sleeping sickness in 25 years. an opportunity to improve the manufacturing of the active pharmaceu- Begun originally as a single centre management of HAT cases. The WHO tical ingredient, its preclinical formula- study by MSF-Holland and Epicentre has already made preparations for the DND i Drugs for Neglected Diseases initiative tion, ADME-PK profi ling and confi rmatory in the Republic of Congo (Brazzaville) arrival of this improved therapeutic studies in animal models of HAT, and the in 2003, this study was extended, as of opportunity and is working to ensure regulatory toxicology package (4-weeks re- 2004, to additional sites in the DRC by that patients have access to NECT by peated dose toxicokinetics in rat and dog, DNDi in collaboration with Epicentre, providing appropriate training and safety pharmacology, and an extensive ge- MSF, STI and the national HAT control supplying the drugs and necessary netic toxicology package). In June 2008, a programmes of the DRC. equipment to disease-endemic full review of the data by DNDi concluded This multi-centre clinical study, countries. The treatment is now available for that fexinidazole was suitable for progres- which enrolled 287 patients and countries to use. In September 2009, sion into clinical development. was completed in 2008, compared the Democratic Republic of the Congo Fexinidazole has entered into Phase I fi rst- the safety and e cacy of NECT, a (DRC), Chad, and the Central African in human clinical studies in September coadministration of the oral drug Republic (CAR) have ordered NECT kits 2009, which makes it the only new drug nifurtimox and the intravenous drug efl ornithine, with efl ornithine to treat patients. candidate in clinical development for monotherapy, the current fi rst-line DNDi and partners are conducting sleeping sickness. A tablet formulation is treatment for stage 2 T. b. gambiense a fi eld study, which began enrolling underway. In May 2009, DNDi and sanofi - HAT. As is requisite to establish e cacy patients in April 2009, to further aventis have signed an agreement for the in this disease, patients were actively document the safety and ease of use development, manufacturing and distribu- followed up for 18 months after of the combination in real-life fi eld tion of fexinidazole. Under the terms of the treatment. conditions and in special populations agreement, DNDi will be responsible for The study conclusively demonstrated like children. non-clinical, clinical, and pharmaceutical that NECT is as well-tolerated and development and sanofi -aventis will be re- sponsible for the industrial development, registration, and production of the drug at Recognized by the board of DNDi as its manufacturing sites. This project and the preclinical results “Project of the Year 2008” were presented during the 2008 meeting of American Society of Medicine & Tropical (1) Nifurtimox-efl ornithine combination therapy for second-stage African gambiense Hygiene, and are available at www.dndi.org. trypanosomiasis: a multicentre, randomised, phase III, non inferiority trial”, Priotto G, Kasparian S, Mutombo W, Ngouama D, et al.,Lancet, 4 July 2009;. 374 (9683): 56 – 64.

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SLEEPING SICKNESS © Human African Trypanosomiasis (HAT) 60 million people at risk in sub-Saharan

WHAT IS THE ANNUAL IMPACT OF HAT? WHERE DOES HAT OCCUR? 50,000-70,000 cases (1) Of the 36 countries considered endemic 48,000 deaths (2) for HAT, the 7 most a› ected countries 1,525,000 DALYS (3) represent 97% of all reported cases (see map). The Democratic Republic of the Congo Large proportions of communities can be (DRC) alone accounts for 2/3 of reported a› ected by HAT, with serious social and T.b. gambiense cases (4). HAT primarily occurs in the poor economic consequences. Epidemics at the and rural areas of Africa, where di culty end of the 20th century infected up to 50% T.b. rhodesiense of diagnosis, political instability, and lack of population in villages across rural Africa. health surveillance make estimates of disease prevalence di cult to ascertain. HOW IS HAT TRANSMITTED? Transmitted to humans by tsetse fl ies, HAT WHAT ARE THE SYMPTOMS AND is caused by two sub-species of the parasite, PRESENTATIONS? Trypanosoma brucei: T. b. gambiense (west HAT occurs in two stages: and central African), T. b. rhodensiense (east Stage 1 – the haemolymphatic phase – includes and southern African). non-specifi c symptoms like headaches and bouts of fever (generally goes undiagnosed WHAT ARE THE CURRENT TREATMENTS AND THEIR LIMITATIONS? without active HAT surveillance). Available treatments are few, old, and stage- Stage 2 –the later, neurologic phase – occurs specifi c. Stage 1 treatments, pentamidine and when the parasite crosses the blood-brain are fairly well-tolerated but still require barrier and can lead to serious cycle injections and are mostly ine› ective in stage 2. disruptions, , progressive mental DND i Drugs for Neglected Diseases initiative For stage 2 (where most patients are diagnosed deterioration, and, ultimately, results in death and thus treated), 3 available treatments exist: without e› ective treatment. melarsoprol, an derivative that is painful, toxic (killing 5% of those who receive it), and increasingly ine› ective (up to 50% resistance and treatment failure). WHAT IS DNDi DOING TO ADDRESS efl ronithine, di cult to administer, requires UNMET TREATMENT NEEDS? trained health sta› and constant hospitalization Short term: better use of existing treatments (requiring 56 infusions of 2 hours each over 14 days), and resistance is an increasing concern. – Nifurtimox-efl ornithine combination therapy (NECT), a simplifi ed treatment for stage 2 HAT, now ready for use NECT (nifurtimox-efl ornithine combination therapy), is available since September 2009. Medium term: drug candidates identifi ed through compound mining NECT was developed by DNDi and its partners – Fexinidazole: fi rst drug candidate entered clinical development from and is an improved therapy option for sleeping nitroimidazoles project sickness. But is still far from an ideal, treatment – Back-up nitroimidazoles identifi ed that would improve management case at the Long term: discovery of promising new drug candidates and improved community level. clinical research capacity – New drugs developed from compounds identifi ed (i.e. oxaboroles) WHAT ARE THE PATIENT TREATMENT in discovery research and progressed through HAT lead optimisation NEEDS? consortium – A safe, e› ective, and practical stage 2 treat- – Multi-country, multi-partner HAT Platform to strengthen regional ment would improve and simplify current case research capacity (see Section 3). management. This drug should ideally work in both stages of the disease. By 2014, DNDi aims to deliver from its HAT-specifi c portfolio: – A simple stage 1 treatment, to be used at the – 1 new combination therapy recommended by WHO local health centre level, would increase access – 1 new drug registered to treatment and coverage. – A robust pipeline

(1) World Health Organization (WHO). Wkly Epidemiol Rec. 2006:81;71-80. (2) The World Health Report. Geneva; 2004. Available from http://www.who.int/whr/2004. Accessed Aug 12, 2008. (3) DALYs are a measure of societal impact, being the sum of years of potential life lost due to premature mortality and the years of productive life lost due to disability. (4) Simaro PP, Jannin J., Cattnd p; ploS Med. 2008;5:e55.

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