Sirnaomics Leading siRNA Therapeutic Candidate, STP705, Granted Orphan Designation for PSC


Sirnaomics, Inc., a leading biopharmaceutical company in discovery and development of RNAi therapeutics, announced today that the Office of Orphan Product Development division of the USA FDA has granted Orphan Drug Designation to its leading therapeutic candidate, STP705, for the treatment of Primary Sclerosing Cholangitis (PSC).


Sirnaomics lead product candidate, STP705, is an anti-fibrosis and anti-inflammatory siRNA (small interfering RNA) therapeutic which takes advantage of a dual-targeted inhibitory property and polypeptide nanoparticle (PNP)-enhanced delivery to directly diminish both fibrotic and inflammatory activity. The product has received both US FDA and Chinese FDA IND approval for Hypertrophic Scar Reduction and it is expected to have efficacy in many diseases across therapeutic areas. The Orphan Drug application was supported by recent studies in vivo that revealed improvement in serum biomarkers and improved fibrosis scoring in CCL4 induced liver fibrosis models.


“This is a very significant milestone for Sirnaomics and a strategy we are taking to accelerate our novel siRNA therapeutic programs into clinic and finally to the patient,” stated Dr. Patrick Lu, founder and CEO. “The fact that we are able to achieve this designation speaks to the company’s ability to execute on its commitment to investors. This is the third major clinical milestone we have achieved in the past six months including our FDA and CFDA IND approval for STP705 for the treatment of Hypertrophic scar reduction. The future looks very encouraging for Sirnaomics and we are very excited to continue our recent noteworthy progress as we move towards multiple clinical programs in 2017 and 2018.”


“The Orphan designation for PSC is potentially a major win for the clinical management of this devastating disease,” stated Dr. Michael Molyneaux, Sirnaomics, Inc. CMO. “It fits very well with our mission to alleviate human suffering and target diseases with high unmet clinical need and, with the current progress of our ongoing IND enabling studies for treatment of human liver fibrosis, we anticipate filing an IND for PSC sometime in the first half of 2018.  PSC is a devastating disease and it is our hope that our ongoing clinical development can lead to a viable treatment alternative for patients living with this disease.”




About PSC


Primary sclerosing cholangitis (PSC) is a chronic fibrotic disease of the liver that causes damage to the bile ducts. Bile is a digestive liquid that is made in the liver and travels through the bile ducts to the gallbladder and the small intestine, where it helps digest fats and fatty vitamins. In patients with PSC, the bile ducts become blocked due to inflammation and fibrosis. This causes bile to accumulate in the liver, where it damages liver cells causing fibrosis and eventually leading to cirrhosis. As cirrhosis progresses the liver slowly loses its ability to function. The scar tissue may block drainage of the bile ducts leading to infection. Many people with PSC will ultimately need a liver transplant, typically about 10 years after being diagnosed with the disease. Patients with PSC also have a very high risk of development of an untreatable form of bile duct cancer known as cholangiocarcinoma. There is currently no approved medical therapy for PSC.


Studies have shown that significantly higher expression of TGF-β1 was observed in PSC patient liver samples compared to healthy controls and COX-2 was strongly expressed in PSC-associated Cholangiocarcinoma (CCA) tissues compared with non-neoplastic bile duct epithelial cells (BDECs) in PSC patients. Therefore, STP705’s dual-targeted property will be a promising approach for PSC treatment.




About STP705


STP705 is composed of two siRNA oligonucleotides, targeting TGF-β1 and COX-2 mRNA respectively, and formulated in nanoparticles with Histidine-Lysine Co-Polymer (HKP) peptide. Each individual siRNA was demonstrated to inhibit the expression of their target mRNAs and combining the two siRNA’s produces a synergistic effect that diminishes pro-fibrogenic and pro-inflammatory factors. Molecular analyses of the effects of administering the combination demonstrated that the inhibition of these targets had effects on downstream gene products associated with fibrosis including: α-SMA, Col1A1, and Col3A1. Additional data suggests that reductions in TGF-β1 and COX-2 led to proapoptotic effects in fibroblasts. These observations suggest that STP705 has the potential for broad application in many inflammatory and fibrotic driven disease states.




Orphan Drug Designation


The Orphan Drug Act (ODA) from US FDA provides for granting special status to a drug or biological product (“drug”) to treat a rare disease or condition upon request of a sponsor. This status is referred to as orphan designation (or sometimes “orphan status”). For a drug to qualify for orphan designation both the drug and the disease or condition must meet certain criteria specified in the ODA and FDA’s implementing regulations at 21 CFR Part 316. Orphan designation qualifies the sponsor of the drug for various development incentives of the ODA, including tax credits for qualified clinical testing. A marketing application for a prescription drug product that has received orphan designation is not subject to a prescription drug user fee unless the application includes an indication for other than the rare disease or condition for which the drug was designated.




About Sirnaomics, Inc.

Sirnaomics, Inc., a leading privately held biopharmaceutical company for discovery and development of RNAi therapeutics, is a Delaware corporation headquartered in Gaithersburg, Maryland, USA, with subsidiaries in Suzhou and Guangzhou, China. The Company’s mission is to develop novel therapeutics to alleviate human suffering and advance patient care in areas of high unmet medical need. The guiding principles of the company are: Innovation, Global Vision with a Patient Centered focus. Members of the senior management team have a great deal of combined experience in the biopharmaceutical industry, financial, clinical and business management in both the USA and China. The company is supported by funding from institutional investors and corporate partnerships. Sirnaomics has developed a strong portfolio of intellectual property with an enriched product pipeline. The therapeutic areas of focus include oncology and anti-fibrotic therapeutics. Learn more at