- Email: [email protected]
Biological barriers and nanomedicine – Timely challenges in advanced drug delivery research
European Journal of Pharmaceutics and Biopharmaceutics 72 (2009) 287–288
Contents lists available at ScienceDirect
European Journal of Pharmaceutics and Biopharmaceutics journal homepage: www.elsevier.com/locate/ejpb
Editorial
Biological barriers and nanomedicine – Timely challenges in advanced drug delivery research q To address nanotechnology applications for medical purposes, the term ‘‘Nanomedicine” is becoming increasingly popular. Apart from the medical use of nanomaterials or nanoelectronic biosensors, major expectations are on nanomedicines when it comes to delivering notoriously ‘‘difficult” compounds, such as amino acidand nucleic acid-based drugs, across biological barriers, or to targeting anticancer or anti-inflammatory drugs to specific cells or organs. In this context it is worth memorizing that the term ‘nanoparticle’ was introduced into the pharmaceutical literature already in the early 1970s by Peter Speiser and his followers Patrick Couvreur and Jörg Kreuter – much earlier in fact than the very popular use of this term nowadays by solid-state physicists, physico-chemists or material scientists. Notably, however, Pharmaceutical Nanotechnology - which might be an interesting alternative to the term Nanomedicine- has to do with much more than just the small size of some new drug carriers, as recently commented by another nestor of this field, Alexander. T. Florence (A.T. Florence, Pharmaceutical nanotechnology: More than size - Ten topics for research, Int. J. Pharm. 339 (2007) 1–2) . Besides – of course! – the proper physico-chemical characterisation of nanomedicines, the investigation of their biological properties is a major issue. While the first nanoparticle formulations of anticancer drugs have been approved based on the demonstrable therapeutic advantages in the clinic, new types of nanoparticles for other advanced drug delivery applications are continuously being explored. In contrast to technical nanoparticles, biocompatibility and safety of the materials used in pharmaceutical nanoparticles are an absolute must. Obviously, materials with an established safety profile as pharmaceutical excipients are preferred, but there is also a need to look for new ones with improved technological or biopharmaceutical properties. Of course the safety of such novel materials has to be demonstrated. In this context, cell- and tissue-based in vitro models of certain biological barriers are generally accepted to be most useful. While their potential to replace, reduce and refine animal experiments is a clear ethical and economical advantage of in vitro techniques, they also offer an advantage from a mere scientific point of view, namely to reduce the inherent complexity of in vivo models. While, of course, only in vivo testing can prove the safety and efficacy of a new drug product, advanced in vitro test models have unique added value to understand the mechanisms of some advanced drug carriers, and moreover can
q Editorial comments: EJPB Special Issue, featuring selected papers of the7th International Conference and Workshop on Biological Barriers and Nanomedicine – Advanced Drug Delivery and Predictive non vivo Testing Technologies 20–29 February 2008, Saarland University, Saarbrücken, Germany.
0939-6411/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.ejpb.2009.04.002
be quite useful for saving time and costs towards the first proof of concept in man. International and multidisciplinary research training in areas, such as nanomedicine and cell- and tissue-based in vitro models, was also in the focus of the ‘‘GALENOS Euro-PhDÒ program. The GALENOS Network in Pharmaceutical Sciences (http://www. galenos.net) is 15 years old and its membership has grown to approximately 70 partner institutions. One of its startling initiatives was the establishment of: the ‘‘Galenos Euro-PhDÒ in Advanced Drug Delivery” as a formal European postgraduate certificate on top of the ‘‘regular” doctoral degree obtained from the student’s home university. The Euro-PhD certificate distinguishes young pharmaceutical scientists who have participated in international research training and completed a significant piece of research at a competitive level. Euro-PhD candidates must have (1) successfully completed a doctoral thesis on a subject relevant to the field of Drug Delivery, (2) published at least one paper in a peer-reviewed journal, (3) worked for at least 12 months at a research facility in a foreign country, and (4) attended a significant number of approved postgraduate courses, such as the biannual ‘‘Cellcourse” at Saarland University. The GALENOS Euro-PhD program received substantial funding from the Marie Curie Program of the EC from 2004 to 2008 (MEST-CT-2004-504992) which is herewith gratefully acknowledged. So far, more than 40 fellows have been enrolled, and until now 20 of them have completed all Euro-PhD requirements. Together, the fellows have published 39 papers and 4 patent applications, won numerous awards and were offered attractive positions in academia and industry. The present special issue of EJPB compiles some selected papers presented at the 7th International Conference and Workshop (‘‘Cellcourse”) on Biological Barriers and Nanomedicine – Advanced Drug Delivery and Predictive non-vivo Testing Technologies, which took place during 20–29 February 2008 at Saarland University, Saarbrücken, Germany under the auspices of the GALENOS Network. Due to its particular relevance as biological barrier in the context of nanomedicine, but also in the context of nanotoxicology, the first seven papers of this special issue deal with the SKIN BARRIER, the following four papers focus on the AIR-BLOOD BARRIER OF THE LUNGS and three more papers focus on OTHER BARRIERS AND TECHNOLOGIES. As the past special issue on the 5th ‘‘Cellcourse” in 2004 (EJPB 60 (2005) – 167–316), we hope that this EJPB Special Issue provides a vivid picture of today’s research on cell culture models of biological barriers, especially in the context of nanomedicine. As an editor of EJPB and organizer of the past 7th conference, I wish to thank all the speakers, teachers and participants, and I specially thank the contributors of the papers of this special issue which all underwent a rigorous peer review, some-
288
Editorial / European Journal of Pharmaceutics and Biopharmaceutics 72 (2009) 287–288
times requiring major revisions, but justifying that it thus took a little more time to publish this special issue. Finally, by the time this special issue appears, the next ‘‘Cellcourse” will be looking round the corner. The upcoming 8th International Conference and Workshop will have a special focus on Biological Barriers, Nanomedicine and Nanotoxicology and will take place during 21 March–1 April 2010. For details of the program and registration, visit http://www.uni-saarland.de/ cellcourse2010.
Claus-Michael Lehr Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University, Saarbrücken, Germany Tel.: +49 0 681 302 3140; fax: +49 0 681 302 4677. E-mail address: [email protected]
Contents lists available at ScienceDirect
European Journal of Pharmaceutics and Biopharmaceutics journal homepage: www.elsevier.com/locate/ejpb
Editorial
Biological barriers and nanomedicine – Timely challenges in advanced drug delivery research q To address nanotechnology applications for medical purposes, the term ‘‘Nanomedicine” is becoming increasingly popular. Apart from the medical use of nanomaterials or nanoelectronic biosensors, major expectations are on nanomedicines when it comes to delivering notoriously ‘‘difficult” compounds, such as amino acidand nucleic acid-based drugs, across biological barriers, or to targeting anticancer or anti-inflammatory drugs to specific cells or organs. In this context it is worth memorizing that the term ‘nanoparticle’ was introduced into the pharmaceutical literature already in the early 1970s by Peter Speiser and his followers Patrick Couvreur and Jörg Kreuter – much earlier in fact than the very popular use of this term nowadays by solid-state physicists, physico-chemists or material scientists. Notably, however, Pharmaceutical Nanotechnology - which might be an interesting alternative to the term Nanomedicine- has to do with much more than just the small size of some new drug carriers, as recently commented by another nestor of this field, Alexander. T. Florence (A.T. Florence, Pharmaceutical nanotechnology: More than size - Ten topics for research, Int. J. Pharm. 339 (2007) 1–2) . Besides – of course! – the proper physico-chemical characterisation of nanomedicines, the investigation of their biological properties is a major issue. While the first nanoparticle formulations of anticancer drugs have been approved based on the demonstrable therapeutic advantages in the clinic, new types of nanoparticles for other advanced drug delivery applications are continuously being explored. In contrast to technical nanoparticles, biocompatibility and safety of the materials used in pharmaceutical nanoparticles are an absolute must. Obviously, materials with an established safety profile as pharmaceutical excipients are preferred, but there is also a need to look for new ones with improved technological or biopharmaceutical properties. Of course the safety of such novel materials has to be demonstrated. In this context, cell- and tissue-based in vitro models of certain biological barriers are generally accepted to be most useful. While their potential to replace, reduce and refine animal experiments is a clear ethical and economical advantage of in vitro techniques, they also offer an advantage from a mere scientific point of view, namely to reduce the inherent complexity of in vivo models. While, of course, only in vivo testing can prove the safety and efficacy of a new drug product, advanced in vitro test models have unique added value to understand the mechanisms of some advanced drug carriers, and moreover can
q Editorial comments: EJPB Special Issue, featuring selected papers of the7th International Conference and Workshop on Biological Barriers and Nanomedicine – Advanced Drug Delivery and Predictive non vivo Testing Technologies 20–29 February 2008, Saarland University, Saarbrücken, Germany.
0939-6411/$ - see front matter Ó 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.ejpb.2009.04.002
be quite useful for saving time and costs towards the first proof of concept in man. International and multidisciplinary research training in areas, such as nanomedicine and cell- and tissue-based in vitro models, was also in the focus of the ‘‘GALENOS Euro-PhDÒ program. The GALENOS Network in Pharmaceutical Sciences (http://www. galenos.net) is 15 years old and its membership has grown to approximately 70 partner institutions. One of its startling initiatives was the establishment of: the ‘‘Galenos Euro-PhDÒ in Advanced Drug Delivery” as a formal European postgraduate certificate on top of the ‘‘regular” doctoral degree obtained from the student’s home university. The Euro-PhD certificate distinguishes young pharmaceutical scientists who have participated in international research training and completed a significant piece of research at a competitive level. Euro-PhD candidates must have (1) successfully completed a doctoral thesis on a subject relevant to the field of Drug Delivery, (2) published at least one paper in a peer-reviewed journal, (3) worked for at least 12 months at a research facility in a foreign country, and (4) attended a significant number of approved postgraduate courses, such as the biannual ‘‘Cellcourse” at Saarland University. The GALENOS Euro-PhD program received substantial funding from the Marie Curie Program of the EC from 2004 to 2008 (MEST-CT-2004-504992) which is herewith gratefully acknowledged. So far, more than 40 fellows have been enrolled, and until now 20 of them have completed all Euro-PhD requirements. Together, the fellows have published 39 papers and 4 patent applications, won numerous awards and were offered attractive positions in academia and industry. The present special issue of EJPB compiles some selected papers presented at the 7th International Conference and Workshop (‘‘Cellcourse”) on Biological Barriers and Nanomedicine – Advanced Drug Delivery and Predictive non-vivo Testing Technologies, which took place during 20–29 February 2008 at Saarland University, Saarbrücken, Germany under the auspices of the GALENOS Network. Due to its particular relevance as biological barrier in the context of nanomedicine, but also in the context of nanotoxicology, the first seven papers of this special issue deal with the SKIN BARRIER, the following four papers focus on the AIR-BLOOD BARRIER OF THE LUNGS and three more papers focus on OTHER BARRIERS AND TECHNOLOGIES. As the past special issue on the 5th ‘‘Cellcourse” in 2004 (EJPB 60 (2005) – 167–316), we hope that this EJPB Special Issue provides a vivid picture of today’s research on cell culture models of biological barriers, especially in the context of nanomedicine. As an editor of EJPB and organizer of the past 7th conference, I wish to thank all the speakers, teachers and participants, and I specially thank the contributors of the papers of this special issue which all underwent a rigorous peer review, some-
288
Editorial / European Journal of Pharmaceutics and Biopharmaceutics 72 (2009) 287–288
times requiring major revisions, but justifying that it thus took a little more time to publish this special issue. Finally, by the time this special issue appears, the next ‘‘Cellcourse” will be looking round the corner. The upcoming 8th International Conference and Workshop will have a special focus on Biological Barriers, Nanomedicine and Nanotoxicology and will take place during 21 March–1 April 2010. For details of the program and registration, visit http://www.uni-saarland.de/ cellcourse2010.
Claus-Michael Lehr Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University, Saarbrücken, Germany Tel.: +49 0 681 302 3140; fax: +49 0 681 302 4677. E-mail address: [email protected]