SillaJen Publishes Clinical Data Demonstrating Safe Administration of Multiple Intravenous Doses of Oncolytic Virus in Patients with Metastatic Colorectal Cancer

SAN FRANCISCO, June 29, 2015 /PRNewswire/ -- SillaJen, Inc., a private clinical-stage biotherapeutics company focused on the development of oncolytic immunotherapy products for cancer, today announced a publication of data demonstrating that in a Phase Ib trial of Pexa-Vec, patients received multiple bi-weekly doses of its lead product Pexa-Vec, representing the first report of multiple intravenous administrations of an oncolytic vaccinia. Importantly, no dose-limiting toxicities were reported, and the maximum tolerated dose (MTD) was not reached. The trial was conducted in patients with refractory, metastatic colorectal cancer, and the data were published in the journal Molecular Therapy. Dr. Young Suk Park of Samsung Medical Center, Seoul, Korea was the principal investigator on the study and co-author of the report.

"While we have reported dose-dependent antitumor activity in the past with Pexa-Vec, we believe that demonstrating feasibility of administering Pexa-Vec by multiple intravenous infusions broadens the tumor types that can be targeted with this novel oncolytic immunotherapy," stated Eun Sang Moon, chief executive officer of SillaJen. "The data published today show excellent tolerability despite multiple administrations indicating the drug's ability to be administered systemically at regular intervals which may allow the targeting of systemic disease more effectively."

In the Phase Ib trial of Pexa-Vec, 15 patients with treatment-refractory colorectal cancer were enrolled and were given intravenous administrations of Pexa-Vec every 14 days. Nine patients were given infusions at three escalating dose levels, and the cohort receiving the highest dose was then expanded to include an additional six patients given that an MTD was not reached. No treatment related serious adverse events were reported. Ten patients (67 percent) on the study had radiographically stable disease.

"Pexa-Vec has been shown to target and kill tumor cells through multiple mechanisms of action," stated Caroline Breitbach, Ph.D., vice president of clinical and translational research at SillaJen. "The data published today further strengthen the growing body of Pexa-Vec safety and mechanism of action data, particularly relating to systemic Pexa-Vec administration."

About Pexa-Vec
Pexa-Vec is an oncolytic immunotherapy designed to 1) rapidly de-bulk tumors via tumor cell lysis, 2) activate an antivascular effect with rapid tumor vascular knockout, and 3) induce a durable immune response against tumors. Pexa-Vec was derived from vaccinia, which has been used for decades as a vaccine in healthy individuals, and was engineered to selectively target cancer cells. Pexa-Vec was also engineered to express GM-CSF, a white blood cell growth factor leading to the activation of a systemic immune response to kill tumor cells throughout the body. Pexa-Vec has been safely administered to over 300 patients and is currently in clinical development for the treatment of advanced liver cancer (hepatocellular carcinoma).

Pexa-Vec Clinical Development Program
Pexa-Vec is the most advanced product candidate from SillaJen's proprietary SOLVE™ (Selective Oncolytic Vaccinia Engineering) platform. The vaccinia poxvirus strain backbone of Pexa-Vec has been used safely in millions of people as part of a worldwide vaccination program. This strain naturally targets cancer cells due to common genetic defects in cancer cells; Pexa-Vec was engineered to enhance this by deleting its thymidine kinase (TK) gene, thus making it dependent on the cellular TK expressed at persistently high levels in cancer cells. Pexa-Vec is also engineered to express the immunogenic GM-CSF protein. GM-CSF complements the cancer cell lysis of the product candidate, leading to a cascade of events resulting in tumor necrosis, tumor vasculature shutdown and sustained anti-tumoral immune attack.

About SillaJen's Regional Partners for Pexa-Vec

Transgene, part of Institut Merieux, is a publicly traded French biopharmaceutical company focused on discovering, developing and manufacturing targeted immunotherapies for the treatment of cancer and infectious diseases. Transgene's programs utilize viral vector technology with the goal of indirectly or directly killing infected or cancerous cells. The Company's two lead clinical-stage programs are: TG4010 for non-small cell lung cancer and Pexa-Vec for liver cancer. The Company has several other programs in clinical and pre-clinical development that are based on its core viral vector technology. Transgene is based in Strasbourg, France, and has additional operations in Lyon, as well as satellite offices in China and the U.S.  Additional information about Transgene is available at www.transgene.fr.

Green Cross Corp. is a publicly traded and leading Korean biopharmaceutical company specialized in development and commercialization of vaccines, plasma-derivatives, recombinant proteins and therapeutic antibodies in oncology and infectious diseases. Green Cross is well-renowned for its competitive and broad pipeline of drugs across a wide array of diseases, and harbors fully-integrated biologics capabilities across product development processes in multiple therapeutic areas. Green Cross is highly experienced in collaborative opportunities in out-licensing, co-research, co-development and co-marketing projects with various pharmaceutical companies around the world. Additional information about Green Cross Corp. is available at www.greencross.com.

Lee's Pharmaceutical Holdings Limited is a research-based biopharmaceutical company listed in Hong Kong with over 20 years operation in China's pharmaceutical industry. It is fully integrated with strong infrastructures in drug development, manufacturing, sales and marketing. It has established extensive partnership with over 20 international companies and currently has 14 products in the market place. Lee's focuses on several key disease areas such as cardiovascular, oncology, gynecology, dermatology and ophthalmology. Lee's development program is lauded with 47 products stemming from both internal R&D efforts and collaborations with US, European and Japanese companies and aspiring to combat diseases such as liver cancer and pulmonary hypertension. The mission of Lee's is to become a successful biopharmaceutical group in Asia providing innovative products to fight diseases and improve health and quality of life. Additional information about Lee's Pharmaceutical is available at www.leespharm.com.

About SillaJen
SillaJen, Inc. is a South Korean based biotechnology company headquartered in Seoul South Korea, with satellite offices in Busan, South Korea and San Francisco, CA. The company is focused on the development and commercialization of Pexa-Vec an oncolytic immunotherapy product in the SOLVE™ platform for the treatment of advanced primary liver cancer. For more information about SillaJen, please visit www.sillajen.com.

Media Contact:
Jennifer Williams
Cook Williams Communications, Inc.
360-668-3701
[email protected]

SOURCE SillaJen, Inc.

Related Links

http://www.sillajen.com