| Composition for the preservation of viruses -> Monitor Keywords |
|
|
 
Composition for the preservation of virusesRelated Patent Categories: Chemistry: Molecular Biology And Microbiology, Maintaining Blood Or Sperm In A Physiologically Active State Or Compositions Thereof Or Therefor Or Methods Of In Vitro Blood Cell Separation Or TreatmentComposition for the preservation of viruses description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070148629, Composition for the preservation of viruses. Brief Patent Description - Full Patent Description - Patent Application Claims
[0001] This application is a Continuation-In-Part of co-pending application Ser. No. 10/317,171 filed on Dec. 12, 2002, the entire contents of which are hereby incorporated by reference and for which priority is claimed under 35 U.S.C. .sctn. 120. FIELD OF THE INVENTION [0002] The present invention relates to compositions for the preservation of viruses. The present invention also relates to methods for preparing compositions for the preservation of viruses. [0003] It will become apparent from the following description that the viral compositions according to the present invention are most likely to be pharmaceutical compositions for the purposes of vaccination or the delivery of viral particles for gene therapy. However, it must be appreciated that the invention is not to be limited in its application to only pharmaceutical compositions. BACKGROUND OF THE INVENTION [0004] The use of viruses for purposes of vaccination is well known. However, viruses are also becoming increasingly important as tools for gene therapy, and for research and diagnosis. The increasing importance of viruses as tools for medical and other purposes has led to a need to develop viral compositions that may be manufactured, stored and used without compromising viral efficacy. [0005] For example, viral compositions for vaccination must be able to maintain the immunogenicity of a virus, or the immunogenicity of a component of the virus. In the case of compositions of viruses to be used for gene therapy, it is critical that the efficacy of the live viral formulations carrying therapeutic transgenes be maintained. [0006] The use of viruses for vaccination purposes generally involves the vaccination with live attenuated or altered viruses, vaccination with inactivated viruses, or vaccination with one or more immunogenic components of the virus. Examples of viral infections that are vaccinated against during childhood include varicella virus, poliovirus, measles virus, mumps virus, rubella viruses, and hepatitis viruses. [0007] Because viruses are also highly efficient at infecting susceptible cells, viruses are now recognised as being useful vehicles for the transfer of therapeutic nucleic acids into cells for the purpose of gene therapy. Gene therapy broadly refers to the transfer of genetic material into cells and the expression of that material in those cells for a therapeutic purpose. The goal is to produce the desired protein in the appropriate quantity and the proper location. Although a variety of methods have been developed to deliver therapeutic nucleic acids to cells, many of these methods are limited by relatively inefficient transfer of the therapeutic nucleic acid to the target cells. Due to their efficiency at infecting cells, viruses are suitable vehicles for the transfer of therapeutic nucleic acids into cells for the purpose of gene therapy. [0008] In this regard, viruses fall broadly into two distinct groups: those that integrate into the genome of transduced cells and those that do not. An integrating virus inserts its viral genome into host DNA to facilitate long-term gene expression. For a non-integrating virus the viral genome exists extra-chromosomally as an episome in the nucleus of transduced cells. Depending on the ability of the virus to replicate, the viral genome is either passed on faithfully to every daughter cell or is eventually lost during cell division. [0009] Retroviruses and adeno-associated viruses (AAVs) may integrate into the host DNA to provide a steady level of expression following transduction and incorporation into the host genome. As the target DNA is replicated, so too is the inserted therapeutic gene embedded in the transferred chromosomal DNA. Thus, transduction via these vectors can produce durable gene expression. This can be advantageous in tumour vaccine strategies in which a steady level of gene expression may enhance efficacy. [0010] In contrast, adenovirus and vaccinia virus vectors do not integrate into the host DNA but exist as episomes. Thus, a transferred gene is expressed without actual integration of the gene into the target cell genome. Generally, non-integrating viruses are used when transient gene expression is desired. [0011] Examples of viruses that may be used to deliver nucleic acids to cells for gene therapy purposes include adenovirus, adeno-associated virus (AAV), retrovirus, herpes simplex virus, vaccinia virus, poliovirus, sindbis virus, HIV-1, avian leukosis virus, sarcoma virus, Epstein-Barr virus, papillomavirus, foamy virus, influenza virus, Newcastle disease virus, sendai virus, lymphocytic choriomeningitis virus, polyoma virus, reticuloendotheliosis virus, Theiler's virus, and other types of RNA and DNA viruses. [0012] Because viruses are biological entities consisting of a nucleic acid encapsulated by a protein coat, they are susceptible to the same chemical and physical processes that may degrade or inactivate proteins and nucleic acids. For example, live or attenuated viruses are often very susceptible to damage, as any change in the conformation or integrity of one or more components of the virus coat or the encapsulated nucleic acid may lead to a loss of infectivity. Viruses and viral components for vaccination purposes are often not very stable and readily become degraded or non-immunogenic, particularly at room temperature. [0013] As such, biopharmaceutical products containing compositions of viruses for vaccination or gene therapy usually require stringent conditions to avoid physicochemical degradation and to maintain biological activity. Degradation of viruses in such compositions may occur during isolation, production, purification, formulation, storage, shipping or delivery of the virus or components of the virus. Accordingly, biopharmaceutical compositions of viruses must be formulated to provide protection of the virus and its components against factors such as temperature, pH, pressure, oxidising agents, ionic content, light, radiation, ultrasound, and changes in phase (for example as occurs during freezing and thawing). [0014] In addition to the factors already discussed, other factors such as viral concentration, the size and structure of the encapsulated nucleic acid, container composition, headspace gas, and number of freeze-thaw cycles may all affect the activity of viral compositions. [0015] As a consequence, the utility of many viruses in biopharmaceutical preparations is often limited by the instability of compositions of the viruses, particularly upon storage. For example, the storage of live viruses at room temperature is particularly problematic, and prevents the use of many viral vaccines in areas where facilities for cold storage are not available or reliable. Indeed, the fact that many viral compositions must be stored at very low temperature, and cannot even be stored at standard freezer temperatures for substantial periods of time represents a serious impediment to the widespread clinical use of many viruses. [0016] In addition, even when some viral compositions are stored at low temperature in the frozen state, a significant loss of infectivity may still occur over time. A further loss of infectivity may occur upon thawing of the frozen viral composition. [0017] As will be also appreciated, the storage of products at standard freezer temperatures may also be problematic, because often such freezers undergo temperature cycling that may result in the viral composition being subjected to temperatures above freezing, and as such the compositions may undergo repeated cycles of freezing and thawing. Freeze-thawing may also occur during large scale production, handling or distribution. [0018] The preparation and storage of viral compositions in the lyophilised, spray-dried or freeze-dried states may also be problematic, as there may be a loss of viral activity upon the change of phase from the liquid to solid state during preparation. A loss of viral activity may also occur upon reconstitution. The use of such forms has the additional disadvantage that upon reconstitution, the viral composition must generally be left for an extended period of time to reconstitute, usually at room temperature. [0019] It would also be advantageous to develop viral compositions that can maintain the desired pH of the composition for extended periods of time despite being exposed to refrigeration temperatures and/or subjected to conditions such as freeze-thawing, especially the slow rate of freeze-thawing that may occur during large scale production, handling or distribution. [0020] Finally, increasingly high concentrations of virus are also being required for vaccination and therapeutic purposes. However, the concentration of virus in a composition may present additional problems to the ability to preserve a virus. In particular, a high concentration of virus may contribute significantly to viral instability due to aggregation and/or precipitation. [0021] Therefore for many viruses a deficiency has been the inability to formulate compositions that acceptably preserve the virus. Such deficiencies with the ability to preserve the activity of viral compositions often preclude their use for vaccination, gene therapy or for other purposes. [0022] It is therefore an aim of the present invention to provide a composition for the improved preservation of viruses. Continue reading about Composition for the preservation of viruses... Full patent description for Composition for the preservation of viruses Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Composition for the preservation of viruses patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Composition for the preservation of viruses or other areas of interest. ### Previous Patent Application: Organ preservation and/or perfusion Next Patent Application: Removal of adenine during a pathogen reduction process in whole blood or red blood cells by dilution Industry Class: Chemistry: molecular biology and microbiology ### FreshPatents.com Support Thank you for viewing the Composition for the preservation of viruses patent info. IP-related news and info Results in 0.18331 seconds Other interesting Feshpatents.com categories: Software: Finance , AI , Databases , Development , Document , Navigation , Error 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
