OncoSec Medical Incorporated Reports Positive Preliminary Efficacy and Safety Results from Phase II Study of ImmunoPulse in Merkel Cell Carcinoma Patients

Data Presented at 27th Annual Meeting of the Society for Immunotherapy of Cancer

SAN DIEGO, Oct. 23, 2012 /PRNewswire/ -- OncoSec Medical Inc. (OTCBB: ONCS), a company developing its advanced-stage ImmunoPulse DNA-based immunotherapy and NeoPulse therapies to treat solid tumor cancers, announced positive preliminary results from a Phase II multicenter trial investigating the use of ImmunoPulse in Merkel cell carcinoma (MCC) patients at the 27th Annual Meeting of the Society for Immunotherapy of Cancer (SITC 2012). The data suggest that ImmunoPulse, which locally delivers a DNA-based cytokine coded for the immune stimulating agent interleukin-12 (DNA IL-12) via electroporation, may elicit increased levels of IL-12 in the tumor microenvironment, which has the potential to result in a systemic immune response in treating aggressive cancers like MCC without serious adverse safety events.

The preliminary results were published in the Journal of Immunotherapy (35(9):721-791, November-December 2012) and will be presented in a poster titled "Intratumoral delivery of Interleukin-12 DNA with in vivo electroporation can lead to regression of injected and non-injected tumors in Merkel cell carcinoma: Results of a phase II study." Dr. Shailender Bhatia, principal investigator and assistant professor at the University of Washington School of Medicine, is lead author and will be presenting the data.

This open-label study is evaluating the ability of ImmunoPulse to increase levels of IL-12 in the tumor microenvironment, in addition to the efficacy and safety of this treatment for patients with MCC. Preliminary results of this study have demonstrated that 100 percent (3/3) of subjects treated with at least one cycle of ImmunoPulse showed an increased level of IL-12 expression in tumor biopsy done three weeks post-treatment as compared to pre-treatment biopsy. Correlative analysis of limited samples demonstrated that at least one subject had increased CD8+ T-cells (also referred to as killer T-cells) in the tumors. Correlative studies of patient samples are ongoing.

Of the first five subjects enrolled, the overall response rate is 20% (1/5). One patient with baseline progressive MCC, despite multiple prior therapies (systemic chemotherapy, surgery, RT, IT interferon) has had a confirmed partial response (greater than 70 percent regression) that persisted for approximately eight months. The regression of injected as well as non-injected tumors, along with no new tumors over six months, suggest successful induction of systemic immune response from local intratumoral immunotherapy in this patient. This subject remains in the study and will receive a third treatment cycle.

Dr. Bhatia commented, "These preliminary results are encouraging, and we are looking forward to continuing our study of ImmunoPulse. We are pleased to see that a patient with progressive MCC, despite failing multiple other therapies, had a confirmed partial response with regression of even distant non-injected tumors. This creative immunotherapy approach to deliver DNA IL-12 directly into the tumors appears to be tolerated well and so far without any systemic side-effects."

All five subjects treated at the time of this preliminary analysis had distant metastatic disease, and were eligible to receive up to two treatment cycles. Two subjects have withdrawn from the study with progressive disease, and only received one cycle of treatment. Three subjects completed the study and received both treatment cycles. To date, the treatment has been safe and well-tolerated, with treatment-related adverse events including transient grade 1 pain (n=5) and grade 1 injection site reaction (n=1) without any systemic or residual toxicity.

Punit Dhillon, President and CEO of OncoSec Medical, added, "These subset data are positive and validate the results seen in our previous clinical trial. Thus far studies have shown that the administration of IL-12 using electroporation safely results in efficient transfection of the agent and a marked increase in production of the IL-12 protein inside the tumor. These results represent the first human data for a gene therapy using in vivo electroporation in MCC patients, and is a positive step towards advancement of this program."

About Merkel Cell Carcinoma

Merkel cell carcinoma is a rare and highly aggressive cancer, with approximately 1,500 new cases each year in the United States, in which malignant cancer cells develop on or just beneath the skin and in hair follicles. The majority of Merkel cell carcinomas appear to be caused in part by a virus, Merkel cell polyomavirus. If this cancer metastasizes to the lymph nodes, the five-year survival rate is about 50 percent. A patient with a small tumor (less than 2 cm) that has not metastasized to the lymph nodes may have a five-year survival rate of more than 80 percent. Current treatment options for these patients is surgery, radiation and chemotherapy; however, up to half of patients suffer a recurrence.

About OncoSec Medical Incorporated

OncoSec Medical Incorporated is a biopharmaceutical company developing its advanced-stage ImmunoPulse DNA-based immunotherapy and NeoPulse therapy to treat solid tumor cancers. ImmunoPulse and NeoPulse therapies address an unmet medical need and represent a potential solution, for less invasive and less expensive therapies that are able to minimize detrimental effects resulting from currently available cancer treatments such as surgery, systemic chemotherapy or immunotherapy and other treatment alternatives.  OncoSec Medicals's core technology is based upon its proprietary use of an electroporation platform to dramatically enhance the delivery and uptake of a locally delivered DNA-based immunocytokine (ImmunoPulse) or chemotherapeutic agent (NeoPulse). Treatment of various solid cancers using these powerful and targeted anti-cancer agents has demonstrated selective destruction of cancerous cells while sparing healthy normal tissues during early and late stage clinical trials. OncoSec's clinical programs include three Phase II clinical trials for ImmunoPulse targeting lethal skin cancers. More information is available at http://www.oncosec.com/.

This press release contains forward looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Any statements in this release that are not historical facts may be considered such "forward looking statements." Forward looking statements are based on management's current preliminary expectations and are subject to risks and uncertainties which may cause our results to differ materially and adversely from the statements contained herein. Some of the potential risks and uncertainties that could cause actual results to differ from those predicted include our ability to raise additional funding, our ability to acquire, develop or commercialize new products, uncertainties inherent in pre-clinical studies and clinical trials, unexpected new data, safety and technical issues, competition and market conditions. These and additional risks and uncertainties are more fully described in OncoSec Medical's filings with the Securities and Exchange Commission. Undue reliance should not be placed on forward looking statements which speak only as of the date they are made. OncoSec Medical disclaims any obligation to update any forward looking statements to reflect new information, events or circumstances after the date they are made, or to reflect the occurrence of unanticipated events.    

SOURCE OncoSec Medical Incorporated