Pfizer’s Regenerative Medicine division and the University College London (UCL) have announced the formation of a partnership for the development of stem cell-based therapies in the treatment of ophthalmic conditions. In particular, the collaboration will focus on the differentiation of human embryonic stem cells (hESCs) into retinal pigment epithelium (RPE) for the treatment of age-related macular degeneration (AMD).
According to Dr. Ruth McKernan, chief scientific officer of Pfizer Regenerative Medicine, "We are excited to be working with pioneers in the field of stem cell ophthalmology from UCL. While we have much to learn about how [embryonic] stem cells can be used therapeutically, we are confident that this relationship will increase that understanding and help us advance to a time when our work may benefit patients worldwide."
Indeed, the world has everything yet to learn, about how, or if, embryonic stem cells could be used therapeutically, since thus far embryonic stem cells have never been used therapeutically, for anything. The only types of stem cells that have ever been used therapeutically are adult stem cells, which are already being used in clinics throughout the world for the treatment of a wide variety of diseases and injuries.
In fact, many scientists are already working on stem cell therapies for eye diseases which do not involve embryonic stem cells, but which instead involve either adult stem cells or iPS (induced pluripotent stem) cells, the latter of which are not naturally occurring stem cells, per se, but instead have been "induced", as the name implies, to exhibit a pluripotency that resembles that of embryonic stem cells. Just last month, for example, in April of 2009, it was reported in the Proceedings of the National Academy of Sciences that cells which had been isolated in the eye and which scientists had previously presumed, as early as 2000, to be retinal stem cells, are instead just ordinary adult stem cells, without any particular predilection toward differentiating into retinal cells. Such a discovery prompted a number of specialists within the ophthalmology field to turn their attention to the re-engineering of iPS cells as the best form of treatment for eye diseases, especially retinal diseases in which the light-sensitive photoreceptor cells degenerate, since these cells could be re-differentiated from iPS cells. Many other eye diseases also involve damage to the layer of ciliary epithelial cells that line the inside of the eye and which contains retinal cells, and iPS cells could be differentiated into these tissue types to treat such diseases. The search for a specific neural stem cell or retinal progenitor cell is therefore no longer as important as it was once thought to be, since iPS can perform the same function. Furthermore, since iPS cells can be developed from cells that are derived from a specific patient who has a specific disease, the iPS cells would already be genetically and immunologically matched to the patient, thereby eliminating any threat of immune rejection. Embryonic stem cells, by sharp contrast, are by their very nature a foreign, heterologous material which for which the obvious and predictable problems of immune rejection have yet to be resolved.
In reference to iPS cells, Dr. Michael Dyer, a member of the St. Jude Children’s Research Hospital Department of Developmental Neurobiology, explains, "This approach would solve many problems of developing cell-based therapy for blindness. First, these cells are immortal, so they can be grown indefinitely to produce large amounts of cells for treatment. And secondly, they would be immunologically matched to the patient, so there would be no danger of rejection. And thanks to some excellent research during the past 15 years, we know a lot about how to reprogram such stem cells to make them into photoreceptors."
Nevertheless, this new partnership between Pfizer and the University College London no doubt represents one of the largest of its kind. According to the terms of the agreement, Pfizer will provide an unspecified amount of funding to UCL, where research will be conducted on the differentiation of embryonic stem cells into retinal pigment epithelium cells, hopefully, for the development of therapeutic applications to both wet and dry age-related macular degeneration as well as other retinal diseases. Pfizer will retain exclusive worldwide rights to commercialize the therapies that result from the research, although it is unclear who exactly will retain the rights to related discoveries that cannot strictly be classified as ophthalmologic in nature.
Age-related macular degeneration affects more than half a million people in Britain alone. According to Professor Pete Coffey of the UCL’s Institute for Ophthalmology, who will direct the project, "We have not only the benefit of Pfizer’s experience of the regulatory process and their expertise in stem cell technology, but the ability, if this works, to produce on a much larger scale. It has huge implications, not only for our project, but for the field of regenerative medicine as a whole."
As the world’s largest research-based pharmaceutical and biomedical company, Pfizer ranks number one in sales in the world, having reported $48.4 billion in revenue in 2007, from which the company invested $8.1 billion into their own research and development. In January of 2009, Pfizer announced its agreement to buy the pharmaceutical giant Wyeth for $68 billion, thereby increasing the scope of its resources even further. Pfizer was founded in 1849 and today employs approximately 81,900 people in more than 150 countries. Pfizer’s launched their Regenerative Medicine unit in November of 2008. (Please see the related news article on this website, entitled, "Business is Booming as Pfizer Targets the Aging Process With New Adult Stem Cell Research", dated November 14, 2008, as originally reported by Bloomberg Press).
Located in central London, University College London was founded in 1826 and today boasts a staff of 8,000 and a student body of over 22,000.
(Please see the related news article on this website entitled, "Pfizer and the University of Wisconsin Form Licensing Agreement", dated May 5, 2009).