Directed differentiation of MSCs by a novel biologic to promote cartilage repair

Funding Type: 
Disease Team Research I
Grant Number: 
DR1-01454
ICOC Funds Committed: 
$0
Disease Focus: 
Skin Disease
Pediatrics
Stem Cell Use: 
iPS Cell
Cell Line Generation: 
iPS Cell
Public Abstract: 
The ability to direct the differentiation of resident mesenchymal stem cells (MSCs) towards the cartilage lineage offers considerable promise in regenerative medicine of articular cartilage after traumatic joint injury or aging-related osteoarthritis (OA). MSCs can be stimulated in vitro to form new functional cartilage. In the OA-affected joint, the repair is insufficient, leaving a damaged matrix suggesting key factors are missing to properly direct the regenerative process. Molecules that activate this potential of cartilage stem cells potentially can prevent further cartilage destruction and stimulate repair of cartilage lesions. Currently there are no disease-modifying therapeutics available for the 40 million Americans suffering from OA. Therapeutic options are limited to oral and intra-articularly injected pain medications and joint replacement surgery. The primary objective of this project is to develop a non-invasive, universal therapeutic for the regeneration of cartilage at any stage of OA. This new therapy will target the resident MSCs in the joint, stimulate production of new cartilage matrix, promote repair and thus limit additional joint damage and improve joint pain and function. From cell-based screens of a unique library of secreted proteins, novel candidates enhancing the formation of articular cartilage (chondrogenesis) from MSCs in vitro were identified. In secondary assays, proteins were assessed for protection of the existing cartilage against induced tissue damage. Through these approaches, the proposed biologic therapeutic OTX-75 was identified to potently promote cartilage differentiation and protect cartilage from inflammatory mediators. Following intra-articular injection in mouse and rat knees, OTX-75 localized to the pericellular matrix, thus reaching the cells in the joint cartilage. OTX-75 did not cause any unwarranted effects in joint tissues or immune responses after 4 weeks. We determined that the chondrogenic activity localizes to the C-terminal domain and subsequently solved its crystal structure. Here we aim to demonstrate the ability of OTX-75 to repair cartilage in vivo in experimental OA in rat, and 2 large animal models. We will characterize the biological activities and identify the binding partners of OTX-75 and its C-terminus as a potential back-up strategy to minimize off-target effects or systemic toxicity. This protein will be developed to meet therapeutic production standards for use in humans and verified for the lack of adverse events. The development of specific biomarkers will allow monitoring of mechanism of action-based efficacy in vivo. These data and reagents will allow the filing of an Investigational New Drug application by the end of the funding period. Successful completion of the program has the potential to lead to the first effective disease-modifying therapy for the approximate 7% of the US population suffering from osteoarthritis.
Statement of Benefit to California: 
Osteoarthritis (OA) is the most prevalent musculoskeletal disease and globally the 4th leading cause of Years Lost to Disease (YLD). OA affects over 40 million Americans and the magnitude of the problem is predicted to increase even further with the obesity epidemic and aging of the baby boomer generation. It is estimated that 80% of the population will have radiographic evidence of OA by age 65 years. The annual economic impact of arthritis in the U.S. is estimated at over $100 billion, representing more than 2% of the gross domestic product. It accounts for 25% of visits to primary care physicians. In 2004 OA patients received 650,000 knee and hip replacements at a cost of $26 billion. Without change in treatment options 1.8 million joint replacements will be performed in 2015. OA is a painful, degenerative type of arthritis; physical activity and working can become difficult or impossible. Some patients with osteoarthritis are forced to stop working because their condition becomes so severe and limiting. OA can interfere with a patient's ability to even perform routine daily activities, resulting in a decrease in quality of life. The goals of osteoarthritis treatment are to relieve pain and other symptoms, preserve or improve joint function, and reduce physical disability. Current therapeutic options are limited to pain medications and joint replacement for patients with advanced disease. No disease-modifying OA drugs are approved for clinical use. The OA problem is thus unparalleled with its clinical and socioeconomic impact and a complete absence of effective therapies. This proposal is aimed at advancing a novel disease-modifying OA drug to the clinic within 4 years. The candidate therapeutic mitigates the underlying cause of OA – specifically joint destruction from abnormal activation and differentiation of cartilage cells. This therapeutic has been developed to act on the resident stem cells, already present in the joint of both normal and diseased joint cartilage, and stimulate the regeneration of cartilage – leading to the improvement of joint function. The development of the novel therapeutic that improves the symptoms and underlying causes of OA would have a significant impact on the well-being of patients and reduce the economic impact resulting from this highly prevalent disease.
Progress Report: 
  • Genetic skin diseases constitute a diverse group of several hundred diseases that affect up to 2% of the population and include common disease such as psoriasis, atopic dermatitis, and wound healing. Patients with one genetic disease, dystrophic Epidermolysis bullosa (EB), lack a normal collagen VII (COL7A1) gene and suffer from debilitating blistering which leads to chronic wounds and scarring that can be lethal by young adulthood. The disease is devastating and despite all efforts, current therapy for DEB is limited to wound care. For recessive dystrophic EB (RDEB) where there is no COL7A1 protein, our EB Disease team has shown that retroviral delivery of the COL7A1 using gene transfer provides a powerful disease modifying activity as autologous, cell-based therapy. In this process, the patient' own cells can be induced to make normal collagen VII. The patients can then receive their own corrected cells back onto their skin. While successful, our initial approach cannot treat many dominantly inherited diseases such as dominant dystrophic EB (DDEB) where a poison subunit inhibits the function of the normal protein. Recent development of induced pluripotent stem (iPS) cells that are generated from the somatic cells of individual patients could provide an ideal source of therapy. Because of recent advances by our team and others in stem cell technology, our hypothesis is that we can create genetically corrected iPS cells for dominant skin diseases such as DDEB as well as recessive diseases such as RDEB. The goal of the EB Disease team is to develop iPS cells of patients with DEB and genetically correct the patient's own collagen VII defect. We then plan to convert the iPS cell back into skin cells that can be grafted onto the patient's wounds. We plan to develop the processes necessary for iPS cell generation, genetic correction and development of a product that can be grafted back onto the patient's own skin. We will be working within the Food and Drug Administration (FDA) in order to create this process while meeting the requirement for successful drug development. Among the FDA requirements are Good Manufacturing Practice (GMP) documenting the purity of the created drug.
  • We have made significant scientific progress during the first year of this grant. Using GMP methods we have developed the initial tools required for successful iPS cell development which will meet the FDA requirements for drug development. We have generated iPS cell lines from subjects with documented DEB and began the processes necessary for genetic correction and future skin grafting of the corrected cells back onto the patient. We are doing extensive testing of the iPS-derived skin cells using human skin tissue models to ensure the safety and efficacy of these cells. Soon we will work together with the FDA and our collaborators to generate patient-specific skin grafts. The ability to therapeutically reprogram and replace diseased skin would allow this procedure to develop therapeutic reprogramming approaches for a variety of both common and life-threatening skin diseases. Moreover, genetically-corrected pluripotent iPS cells could form the basis of future systemic therapies to other organs besides the skin to treat common genetic disorders.
  • Genetic skin diseases constitute a diverse group of several hundred diseases that affect up to 2% of the population and include common disease such as psoriasis, atopic dermatitis, and wound healing. Patients with one genetic disease, dystrophic epidermolysis bullosa (DEB), lack a normal collagen VII (COL7A1) gene and suffer from debilitating blistering which leads to chronic wounds and scarring that can be lethal by young adulthood. The disease is devastating and despite all efforts, current therapy for DEB is limited to wound care. For recessive dystrophic EB (RDEB) where there is no COL7A1 protein, our EB Disease team has shown that retroviral delivery of the COL7A1 using gene transfer provides a powerful disease modifying activity as autologous, cell-based therapy. In this process, the patient's own cells can be induced to make normal collagen VII. The patients can then receive their own corrected cells back onto their skin. While successful, our initial approach cannot treat many dominantly inherited diseases such as dominant dystrophic EB (DDEB) where a poison subunit inhibits the function of the normal protein. Recent development of induced pluripotent stem (iPS) cells that are generated from the somatic cells of individual patients could provide an ideal source of therapy. Because of recent advances by our team and others in stem cell technology, our hypothesis is that we can create genetically corrected iPS cells for dominant skin diseases such as DDEB as well as recessive diseases such as RDEB. The goal of the EB Disease team is to develop iPS cells of patients with DEB and genetically correct the patient's own collagen VII defect. We then plan to convert the iPS cell back into skin cells that can be grafted onto the patient's wounds. We plan to develop the processes necessary for iPS cell generation, genetic correction and development of a product that can be grafted back onto the patient's own skin. We will be working with the Food and Drug Administration (FDA) in order to create this process while meeting the requirement for successful drug development. Among the FDA requirements are Good Manufacturing Practice (GMP), documenting the purity of the created drug. We have made significant scientific progress during the first two years of this grant. We have developed the initial tools required for successful iPS cell development which will meet the FDA requirements for drug development. We have generated iPS cell lines from subjects with documented DEB, identified the genetic mutations, and commenced work on the correction of several mutations in the iPS Cells. We are developing the process necessary for future skin grafting of the corrected cells back onto the patient, and have already successfully generated the initial GMP manufacturing protocols leading to clinical grade, corrected patient skin cells. We are currently doing extensive testing of the iPS-derived skin cells using human skin tissue models to ensure the safety and efficacy of these cells. Soon we will work together with the FDA and our collaborators to generate patient-specific skin grafts. The ability to therapeutically reprogram and replace diseased skin would allow this procedure to develop therapeutic reprogramming approaches for a variety of both common and life-threatening skin diseases. Moreover, genetically-corrected pluripotent iPS cells could form the basis of future systemic therapies to other organs besides the skin to treat common genetic disorders.
  • Genetic skin diseases constitute a diverse group of several hundred diseases that affect up to 2% of the population and include common disease such as psoriasis, atopic dermatitis, and wound healing. Patients with one genetic disease, dystrophic epidermolysis bullosa (DEB), lack a normal collagen VII (COL7A1) gene and suffer from debilitating blistering which leads to chronic wounds and scarring that can be lethal by young adulthood. The disease is devastating and despite all efforts, current therapy for DEB is limited to wound care. For recessive dystrophic EB (RDEB) where there is no effective COL7A1 protein, our EB Disease team has shown that retroviral delivery of the COL7A1 using gene transfer provides a powerful disease modifying activity as autologous, cell-based therapy. In this process, the patient' own cells can be induced to make normal collagen VII. The patients can then receive their own corrected cells back onto their skin. While successful, our initial approach cannot treat many dominantly inherited diseases such as dominant dystrophic EB (DDEB) where a genetically abnormal poison subunit inhibits the function of the normal protein. Recent development of induced pluripotent stem (iPS) cells that are generated from the somatic cells of individual patients could provide an ideal source of therapy. Because of recent advances by our team and others in stem cell technology, our hypothesis is that we can create genetically corrected iPS cells for dominant skin diseases such as DDEB as well as recessive diseases such as RDEB. The goal of the EB Disease team is to develop iPS cells of patients with DEB and genetically correct the patient's own collagen VII defect. We then plan to convert the iPS cells back into skin cells that can be grafted onto the patient's wounds. We plan to develop the processes necessary for iPS cell generation, genetic correction and development of a product that can be grafted back onto the patient's own skin. We are working within the Food and Drug Administration (FDA) in order to create this process while meeting the requirement for successful drug development. Among the FDA requirements are Good Manufacturing Practice (GMP) documenting the purity of the created drug. We have made significant scientific progress during the first three years of this grant. We have developed the initial tools required for successful iPS cell development which will meet the FDA requirements for drug development. We have generated iPS cell lines from subjects with documented DEB. In addition, we have identified the genetic mutations in the iPS cells and corrected several mutations. We are developing the process necessary for future skin grafting of the corrected cells back onto the patient and have already successfully generated the initial GMP manufacturing protocols leading to clinical grade, corrected patient skin cells. We are currently doing extensive testing of the iPS-derived skin cells using human skin tissue models to ensure the safety and efficacy of these cells. The ability to therapeutically reprogram and replace diseased skin would allow this procedure to develop therapeutic reprogramming approaches for a variety of both common and life-threatening skin diseases. Moreover, genetically-corrected pluripotent iPS cells could form the basis of future systemic therapies to other organs besides the skin to treat common genetic disorders.

© 2013 California Institute for Regenerative Medicine