Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
LCC Hybrid molecules as strategy for the design of new anti-infective agents International Symposium « From synthetic chemistry to synthetic biology » Collège de France Paris, 5 mai 2009 Bernard MEUNIER Laboratoire de Chimie de Coordination du CNRS, Toulouse (1979-2006) et PALUMED, Toulouse-Castanet (depuis février 2006) 5 mai 09 1 A hard time for Drug Discovery ! - Drug discovery is highly challenging: - Difficulties to create new drugs - Economical constraints (new drugs should be cheap, even at no-profit level in some cases) - Longer time « from Patent to Market »: 12-15 years, compared to 8 years in the 1960s. - Increase of the R&D costs: 0.8 to 1.4 billion USD ! Break of costs: 10% for discovery, 15% for pre-clinical, 15% for manufacturing and process, 55% for clinical trials and 5% for marketing. 5 mai 09 2 Decrease of the number of approved drugs Only 17 new molecular entities approved by the FDA in 2007. Molecules Costs 5 mai 09 3 Genomics as an answer for drug discovery ? - Glaxo (GSK) spent 7 years on genomic studies on bacteria to evaluate more than 300 gene products as potential targets. - 70 high-through-put screening (HTS) were then performed without success (with large libraries: 300,000 to 500,000 chemicals). - Total cost of the GSK campaign was above 150 M €. Conclusion: there is no « fast-track » from gene to target. 5 mai 09 4 Future trends in drug discovery - Back to natural products as source of new drugs and as inspiration for new scaffolds ! (We should remember Pierre Potier’s predictions). - “Chemical genetics”: study of a gene function with chemical tools (not by genetic knockout as in classical genetics). Observations during clinical trials are in fact “reverse chemical genetics” ! The phenotypic effect of Viagra on the erectile function has been discovered during a clinical trial as vasodilatator for the treatment of heart disease. - Dynamic combinatorial librairies (Lehn et al.) - Development of computational methods to perform virtual screening of targets. 5 mai 09 5 Small molecules as drugs: the downfall or a real future ? - Fast development of “biopharmaceuticals” (proteins, DNA or RNA) over the last two decades. - New efficient vaccines. - Highly specific antitumoral antibodies….etc. - In 2008, the drug market is still dominated by small molecules (80%), but this ratio will decrease, slowly or quickly ? (the high cost of “biological drugs” will probably limit their developments). 5 mai 09 6 Limits for health costs ? - Health costs reached 16% of the gross domestic product (GDP) in the USA in 2005. - What will the limit (or the plateau) for health costs in a developed country: 20%, 25% ? - A Swedish survey in 2003 indicates that the annual cost of antirheumatic antibodies is 12,000 €/year, compared to a cost of 170 €/year/person for chemical drugs. 12,000 euros = the price of a medium-size car. 5 mai 09 7 Did we reached the limits of the vast chemical space ? No Fink and Reymond generated in 2007 a database of 26 million molecules with up to 11 atoms of carbon, nitrogen, oxygen and fluorine that are feasible (only 63,850 molecules of this limited chemical space are already in public databases, i.e. 0.24%). 5 mai 09 Cartoon view of the chemical space and discrete areas occupied by inhibitors of kinases, proteases, ….etc. 8 Why making hybrid molecules as potential drugs ? - Nature is making hybrid molecules ! - The antitumoral bleomycin is a good example of a hybrid molecule with three different domains (DNA binding, metal binding and cell penetration). H2N * O NH2 H N NH2 * N* N C H3 Metal binding domain O H2N C H3 HN * O Cell penetration 5 mai 09 DNA binding domain O HO O N H N* H N O O NH O C H3 HO C H3 S N N R S + ble om ycin A 2 R = -NH-(C H2)3-S (C H3)2 ble om ycin 2B R = -NH-(C H2) 4-NH-C (=NH)-NH2 N H L-gu l ose -D-m an n ose 9 Different strategies for making hybrid molecules A = one single target single target single target (double-edged sword molecules) B = two independent targets target 1 target 2 (the two entities of the hybrid molecule act independently on the targets) C = two related targets target 1 target 2 (both entities of the hybrid molecule act at the same time) B. Meunier, Acc. Chem. Res., 41, 69-77 (2008) 5 mai 09 10 Mechanism-driven design of trioxaquines® Requirements for antimalarial drug design: (i) bitherapy is recommended to avoid the emergence of resistant parasite strains (=> hybrid molecules) (ii) different pharmacokinetics of two independent drugs are generating difficulties in bitherapy. Trioxaquines are based on a strategy using «hybrid molecules with a dual mode of action»*. The two active entities are covalently linked to synchronize their biodisponibility. trioxane pharmacophore n° 1 linker quinoline Trioxane-linker-quinoline = « trioxaquine » pharmacophore n° 2 The trioxaquines are highly active on chloroquine-resistant Plasmodium falciparum. Dechy-Cabaret et al., CNRS patent, April 2000. *For 5 mai 09 a review, see Meunier, Acc. Chem. Res., 2008, 69-77 11 Current status of the development of trioxaquines - 120 trioxaquines and trioxolaquines have been prepared by Palumed and evaluated in vitro (IC50 values) between February 2003 and December 2006. - 77 of these hybrid molecules have been evaluated in vivo (mice model, determination of CD50 and CD90 values). - 6 of these trioxaquines have been further evaluated. - PA1103 has been selected in January 2007 for development by Sanofi-aventis (= SAR116242). - 3 kg have been prepared in March 2008. 12 kg of the GMP product are currently in production. 5 mai 09 12 Structure of the trioxaquine PA1103/SAR116242 PA1103 is a 50/50 mixture of two diastereoisomers Coslédan et al., PNAS, vol. 105, 17579-17584 (2008) 5 mai 09 13 Properties of PA1103 (selected as drug-candidate) - Molecular weight: 460 (base form) (OK with the Lipinski’s rules) - Crystalline form, log P calc. = 4.9 - Stable at 50 °C for months. - Stable at acid pH values for hours. - Ames negative. - Cardiosafety is OK. - Good metabolic profile (only one main metabolite). - PK studies (rat): biodisponibility = 30-35%. - IC50 value on P. falciparum CQ-resistant FcM29 = 9 nM. - IC50 values on six different strains = from 7 to 15 nM. - PA1103 is active on clinical isolates (Africa). 5 mai 09 14 PA1103 has a dual mode of action: . Inhibition of heme polymerization like chloroquine. . Alkylation of heme like artemisinin. . Active on the early stages of the multiplication within the red bloods like artemisinin. . Active on gametocytes like artemisinin. Coslédan et al., PNAS, vol. 105, 17579-17584 (2008). 5 mai 09 15 New antibiotics: a real medical need • « After the decline: facilitating a renewal in antibiotic development » WHO (2004) and EASAC (European Academies Science Advisory Council, 2007). • « Despite the critical need for new antimicrobial agents, the development of these agents is declining. Solutions encouraging and facilitating the development of new antimicrobial agents are needed » (Spellberg et al., Clinical Infectious Diseases, 2004, 38, 1279-1286). • In 2004, among 506 drug-candidates in development in pharma’ and biotech’ companies, 67 are for cancer, 33 for inflammation, 34 for metabolic disorders and only 6 for bacterial infectious diseases (same authors as above). 5 mai 09 16 PALUMED has identified three different targets for new antibiotics • Nosocomial infections (vancomyquine®). The number of MRSA-related hospitalization doubled within 7 years (19992005) and the number of deaths due to nosocomial infections (19,000/year) is higher than that related to AIDS (E. Klein et al. CDC-Atlanta, www.cdc.gov.eid, December 2007). • An anti-MRSA antibiotic active by oral administration (cephaloquine®). A cephalosporin-antibiotic active by oral route is deeply needed. • An antibiotic active on drug-resistant gram-negative bacteria (bactamiquine®). Multidrug-resistant gram-negative bacteria are responsible for nosocomial pneumoniaattributed mortality (Pseudomonas aeruginosa, Acinetobacter spp, …). Names in blue are corresponding to PALUMED’s programs. 5 mai 09 17 Antibioquines® as new antibiotics - To fight bacteria resistant to classical antibiotics, PALUMED extended the concept of hybrid molecules named « antibioquines® » (Patent applications 2004, 2009). - Concept : covalent attachment of an aminoquinoline entity (AQ) to an antibiotic skeleton. 5 mai 09 Linker Antibiotic moiety HN R1a R1b N 18 Bactericidal activities of vancomyquines compared to vancomycin, linezolid, telavancin and daptomycin against S. aureus MRSA with 50% of human serum Vancomycin Telavancin Daptomycin PA1247 PA1274 PA1409 PA1410 PA1418 - - - - - - - - - Q L - - - - - - N-R MIC without serum - - - - - - - - 1 0.5 0.5 0.125 0.25 0.125 0.5 0.25 MIC with serum 2 2 4 0.5 0.5 0.5 0.5 0.25 3 Concentration: 1 mg/mL (MIC values obtained by macro-methods) 2 Control Vancomycin 1 Daptomycin 0 D log cfu Only vancomyquines are able to reduce the bacterial colonies by 4.5 log units within 24 h at 1 mg/mL compared to vancomycin, telavancin, linezolide or daptomycin. Linezolid -1 Telavancin -2 PA1410 -3 PA1247 PA1274 PA1409 PA1418 -4 For PA1409: 1 mg/mL = 0.57 mM -5 0 5 mai 09 4 8 12 Time (h) 16 20 24 19 PA1409: influence of inoculum on its bactericidal activity against S. aureus MRSA (clinical isolate mR) with 50% of human serum MICs (values obtained by macro-method, bactericidal conditions) Vancomycin Daptomycin Inoculum: 105 CFU/mL MIC without serum MIC with serum Inoculum: 107 CFU/mL MIC without serum MIC with serum 1 2 2 2 2 2 Telavancin 0.5 2 16 8 PA1409 0.125 0.5-1 2 2 0.5 1 PA1409 is the most active at a low dose Bactericidal activities at a concentration = 2 mg/mL Small inoculum: 105 CFU/mL 3 High inoculum: 107 CFU/mL 2 Control 1 Control D log cfu 0 Vancomycin PA1409 Telavancin -1 -2 Telavancin Daptomycin -3 Vancomycin -4 Daptomycin PA1409 -5 5 mai 09 Time (h) 0 4 8 12 16 Time (h) 20 20 24 Bactericidal activity on E.faecalis VSE (Isolat U38) or VRE Van A (CIP106996) with 50% of human serum at 4 µg/mL Studies 08-831/37 et 07-831/23 Vancomycin E.faecalis VSE: 1 1 1–2 0.06 MIC with serum 4 4 4 2-4 256 8 1 1 > 256 4 4 2-4 MIC with serum E. faecalis VSE- 4 µg/mL E. faecalis VRE - 4 µg/mL 5 Control 4 3 3 2 2 1 Vancomycin 0 Telavancin -1 -2 Vancomycin Telavancin 1 Daptomycin 0 -1 PA1409 -2 Daptomycin -3 Δlog CFU/mL Δlog CFU/mL 5 Control 4 PA1409 MIC without serum MIC without serum E.faecialis VRE: Daptomycin Telavancin -3 PA1409 -4 -4 -5 -5 0 4 5 mai 09 8 12 Time (h) 16 20 24 0 4 8 12 Time (h) 16 20 21 24 Bactericidal activity on E.faecium VSE (Isolat B1003) or VRE Van A (CIP107387) with 50% of human serum at 16 µg/mL Studies 08-831/38 et 08-831/29M Vancomycin E.faecium VSE: 0.5 0.06 0.06 MIC with serum 2 2-4 1 0.125 MIC without serum > 256 2-8 0.25 4-8 MIC with serum > 256 256 8 - 16 64 E. faecium VSE-16 µg/mL E. faecium VRE-16 µg/mL 5 5 4 4 Control 3 3 2 2 1 Vancomycin PA1409 Δlog CFU/mL Δlog CFU/mL PA1247 0.5 MIC without serum E.faecium VRE: PA1409 Telavancin PA1247 0 -1 Control Vancomycin Telavancin 1 PA1247 PA1409 0 -1 Telavancin -2 -2 -3 -3 -4 -4 -5 -5 0 4 5 mai 09 8 12 Time (h) 16 20 24 0 4 8 12 Time (h) 16 20 22 24 Vancomyquines®: highly active in vivo on MRSA and PRSP (mice) - Vancomyquine PA1409 is curative by iv route on mice infected by MRSA (septicemia): CD100 = 5 mg/kg. The CD50 value of PA1409 on MRSA = 1 mg/kg. (infection by sc, iv treatment at t°+ 1 h and t° + 4 h) On MSSA: CD80 of PA1409 = 4 mg/kg. On the same MRSA model, the CD100 values of competitors are : Vancomycin: CD100 = 20 mg/kg (no cured mice at 1 mg/kg, CD50 > 5 mg/kg). Telavancin: CD100 = above 20 mg/kg (CD50 = 10 mg/kg). Daptomycin: CD100 = 10 mg/kg (CD50 = 6 mg/kg). PA1409 is more potent than all the other competitors. - Vancomyquines are curative at 3 mg/kg (sc route) on mice infected by PRSP (no cured animals with vancomycin in the same conditions). 5 mai 09 23 AUC/MIC ratios of PA1409 and vancomycin Dog - adult beagle - 2.5 mg/kg - iv injection - glucose 5 % - Win Non Lin version 5.2 software analysis PA1409 Vancomycin AUC (minxmg/ml) 17105 ± 755 1143 ± 40 MIC90 (mg/ml)* 0.25 1 AUC/MIC 68420 1143 *MIC90 from eleven MRSA strains The AUC/MIC ratio for PA 1409 is 60 times that of vancomycin. 5 mai 09 24 Acknowledgements Mechanism of action of artemisinin derivatives Anne ROBERT (CNRS Fellow), Jérôme CAZELLES (PhD 2000), Monserrat RODRIGUEZ (post-doct, Spain) Katalina SELMECZI (post-doc, Hungary), Sophie A. -L. LAURENT (PhD 2006) Fatima BOUSEJRA-EL GARAH (PhD student) Financial support : CNRS, PALUMED, ANR and EU-Antimal Synthesis of trioxaquines Frédéric COSLEDAN (Palumed), Christine SALLE (Palumed), Odile DECHY-CABARET (PhD 2001), Christophe LOUP (CNRS), Jérôme CAZELLES (Palumed), Anne ROBERT (CNRS Fellow) Heinz GORNITZKA (X-ray structures) Financial support : PALUMED, CNRS, ANR, Conseil Régional Midi-Pyrénées and EU-Antimal Biological activities of trioxaquines Frédéric COSLEDAN (Palumed), Françoise BENOIT-VICAL (INSERM Fellow), Joël LELIEVRE (PhD), Angélique ERRAUD (Palumed), Carine AUGE (Palumed), Céline BERRONE (Palumed), Katia JONOT (Palumed) Support : PALUMED, ANR, CHU-Rangueil and EU-Antimal Academic collaborations: J. F. MAGNAVAL, J. P. SEGUELA and A. BERRY (Toulouse Hospital, CHURangueil), P. KREMSNER (Lambaréné, Gabon), D. DIVES (Lille, Inserm), D. MAZIER (Paris, Inserm). Collaboration with Sanofi-Aventis : Jean-Pierre MAFFRAND, Laurent FRAISSE, Alain PELLET For informations on PALUMED: see www.palumed.com 5 mai 09 25 Acknowledgements (antibiotics) Synthesis and PK data of antibioquines Muriel SANCHEZ, Jérôme CAZELLES, Michel NGUYEN, Camille CATHARY, Laurence PAGES Biological activities of antibioquines Charlotte DUVAL Collaborations: Christine ROQUES, Faculty of Pharmacy - Toulouse (FONDEREPHAR) Pierre-Louis TOUTAIN, Veterinary School of Toulouse Roland LECLERCQ (CHU-Caen) Bruno FANTIN (CHU-Beaujon, Paris) Financial support: PALUMED 5 mai 09 26