SEOUL, South Korea-Genexine (KOSDAQ: 095700), a publicly traded, clinical-stage Korean biopharmaceutical company committed to the discovery and development of novel biologics for the treatment of unmet medical needs, today announced that GX-188E, its first-in-class proprietary DNA vaccine, demonstrated potent efficacy and favorable safety in patients with advanced cervical cancer in a phase 2 study when given in combination with KEYTRUDA® (pembrolizumab), MSD’s (Merck & Co., Inc., Rahway, NJ, USA) anti-PD-1 therapy.

A total of 60 patients with HPV 16- and/or 18- positive advanced cervical cancer were analyzed in the phase 2 treatment group. Top line results showed a Best Overall Response Rate (BORR) of 31.7% (19 of 60 patients). 6 patients (10.0%) had a complete response and 13 patients (21.7%) had a partial response. Median duration of response (DOR) was 12.3 months and overall survival (OS) was 17.2 months.

The BORR increased to 38.5% in PD-L1 positive patients with HPV 16+ and Squamous Cell Carcinoma. Importantly, PD-L1 negative patients showed an ORR of 25.0%, which is extremely encouraging for this patient population, as it demonstrates potential improvement in efficacy compared to monotherapy of immune checkpoint inhibitors, suggesting a beneficial effect of the combination therapy.

In the safety analysis (n=65) 22 of 65 patients (33.8%) had treatment-related adverse events (TRAEs) of any grade and three (4.6%) had grade 3 or 4 TRAEs. The combination therapy was found to be safe and tolerable with a similar safety profile to that of pembrolizumab monotherapy.

“There is an urgent need for better therapies for patients with advanced cervical cancer and the combination of a therapeutic DNA vaccine together with checkpoint inhibition could be a strong alternative,” said professor Sung-Jong Lee of the Catholic University of Korea, College of Medicine and Investigator in the trial. “The data are very encouraging and appear to show a clear efficacy signal and the product appears safe and well tolerated. I am particularly pleased to see a clear efficacy signal in all patients, regardless of PD-L1 expression. Genexine’s combination therapy has strong appeal from a mechanistic perspective. This approach of using checkpoint inhibition to restore immune system function combined with the vaccine’s effect of upregulating and increasing the influx of CD8+ and other immune cells into the tumor microenvironment, appears to result in a strong, beneficial effect as demonstrated by major outcome measures such as BORR (31.7%) and OS (17.2 months) through the elimination of tumor cells and tumors.”

“We are very pleased to have been invited to present our phase 2 top-line data at ESMO and encouraged by the efficacy and safety shown in this study,” said Neil Warma, President and CEO of Genexine. “The combination of GX-188E, our unique DNA vaccine, with pembrolizumab could represent a new standard of care for patients with HPV 16/18 related recurrent or metastatic cervical cancer, regardless of PD-L1 expression. We are encouraged by the ORR of over 31% but particularly excited by the efficacy signal observed in PD-L1 negative patients. This could open the door to a new therapy for this patient population that previously had limited treatment options available.”

The clinical trial was an open-label, single-arm, phase 2 trial conducted in South Korea in patients with HPV-16 or HPV-18 positive advanced cervical cancer, and who had progressed after standard-of-care therapy. Patients received intramuscular 2 mg GX-188E at weeks 1, 2, 4, 7, 13, 19, and optional dose at week 46, and intravenous pembrolizumab 200 mg every 3 weeks for up to 2 years or until disease progression. The primary endpoint was ORR assessed by the blinded independent central reviewers (BICR) using RECIST version 1.1.

KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC., a subsidiary of Merck & Co., Inc., Rahway, NJ.

About Genexine

Genexine, Inc. is a publicly traded, clinical-stage biotechnology company focused on the development and commercialization of immunotherapeutics and next-generation long-acting biologics. Primary technology platforms are Therapeutic DNA vaccine technology and hyFc® fusion technology. The company has multiple products in clinical development, including several undergoing phase 3 registration trials. The company's proprietary pipeline includes GX-188E for cervical cancer and head and neck cancer, GX-I7 (efineptakin alfa) for multiple cancers, GX-H9 (eftansomatropin alfa) for Growth Hormone Deficiency and GX-E4 for CKD-induced anemia, among others. Genexine has established multiple partnerships with global companies in order to expedite product development and commercialization and create significant value. Genexine is listed on the Korean stock exchange (KOSDAQ: 095700) and is headquartered in Seoul, Korea. Genexine is committed to the well-being and care of patients worldwide.

About GX-188E

GX-188E is a novel DNA-based therapeutic vaccine discovered by Genexine and being jointly developed with the National Cancer Center Korea Onco-Innovation Unit (NOIU). It has a mechanism of inducing an antigen-specific T-cell immune response to E6/E7, a cancer-causing protein produced by HPV types 16 and 18, which are the main causes of cervical cancer. The T cells with activated immune response have an immune-anticancer mechanism that effectively eliminates cervical cancer cells by inducing a cytotoxic T lymphocyte response. Genexine is currently developing GX-188E in cervical cancer and is also conducting two on-going combination trials with GX-188E in Squamous Cell Carcinoma of the Head and Neck (SCCHN).

About Cervical Cancer

Cervical cancer is a cancer arising from the cervix and is due to the abnormal growth of cells that have the ability to invade or spread to other parts of the body. Human Papilloma Virus (HPV) causes more than 90% of cases and HPV 16 and 18 strains are responsible for the majority of high grade cervical cancers. According to WHO, cervical cancer is the fourth most common cancer among women globally, with an estimated 604,000 new cases and 342,000 deaths in 2020. A recent Arizton research report estimated that the cervical cancer therapeutics market was $5.5 billion in 2021 and expected to grow at a CAGR of 4.14% during 2021-2027 to reach $7.1 billion with targeted therapies expected to be the fastest-growing segment during the forecast period.