Kadmon entered into a Cooperative Research and Development Agreement with the NIH’s National Institute of Dental and Craniofacial Research (NIDCR) to develop an adeno-associated virus vector containing the human aquaporin-1 gene (AAV2hAQP1) for the treatment of xerostomia resulting from the use of ionizing radiation (IR) in the treatment of head and neck cancer. Kadmon and NIDCR will also explore the use of the salivary gland as a delivery mechanism for therapeutic proteins into the blood.
A consequence of IR treatment is the irreversible damage to salivary glands resulting in dramatic and permanent reduction in salivary output. Because saliva plays such a critical role in the protection of the tissues of the upper gastrointestinal tract, xerostomia patients suffer considerable morbidity, including oral infections, mucositis, dysphagia, as well as extreme discomfort. There is no adequate therapy currently available to treat this severe condition, which affects approximately 168,000 patients in the U.S.
Kadmon and NIDCR will conduct a Phase I study to test the safety of single escalating doses of AAV2hAQP1. Effectiveness, measured by increase in parotid gland salivary output post-IR, will also be tested for up to three years.
As salivary glands are easily and noninvasively accessible, self-contained, and able to secrete proteins into the bloodstream, the potential exists to use them to express and secrete specific transgene-encoded proteins into the blood. Based on data previously obtained at NIDCR, and using Kadmon's technology for transgene expression and regulation, the parties will seek to optimize conditions for the delivery of therapeutic proteins in patients via salivary glands.
"Xerostomia is a prevalent and debilitating condition, which we are addressing in a unique and durable way through gene therapy," said Olivier Danos, Ph.D., senior vp, molecular medicine, synthetic biology and gene regulation, of Kadmon. "In addition, thanks to the physiology of the human salivary gland, this project allows us to study an area which is of great interest, the transgene-mediated production of therapeutic proteins in patients' salivary glands and their secretion into the blood. We look forward to exploring this potential with NIDCR and its extensive know-how relating to gene transfer into salivary glands."