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David Walsh

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Positive Results Presented from Phase 2 Clinical Trial of Biothera’s Imprime PGG Cancer Immunotherapy in Non-Small Lung Cancer Patients

  • In data presented at an AACR-IASLC joint conference, Imprime PGG met primary endpoint with an Objective Response Rate more than double that of the control group and even greater in Imprime PGG biomarker-positive subgroup.
  • Median Overall Survival for the biomarker-positive Imprime PGG treated subgroup was over 5 months greater than that of the control group.

EAGAN, MN — January 7, 2014 — Biothera today reported positive results from its proof of concept Phase 2 clinical trial in 90 patients with advanced non-small cell lung cancer (NSCLC) at the American Association for Cancer Research and the International Association for the Study of Lung Cancer joint conference on the Molecular Origins of Lung Cancer in San Diego.


The purpose of the open label, multicenter, randomized trial was to evaluate the safety and effectiveness of Biothera’s immunotherapeutic drug candidate, Imprime PGG®, with cetuximab (Erbitux®), carboplatin and paclitaxel compared with the monoclonal antibody and chemotherapy combination alone in previously untreated patients with advanced NSCLC. The primary endpoint of the study was Objective Response Rate and a secondary endpoint was Overall Survival.


“We believe that combination therapies with Imprime PGG may significantly increase survival rates for many cancers, including the most difficult to treat like lung cancer and colorectal cancer, without adding to the toxicity of the backbone therapy,” said Dan Conners, president of Biothera’s Pharmaceutical Group. “The opportunity to provide an effective immunotherapy with overall survival benefits for squamous cell NSCLC patients, a clinically unmet need, is very exciting.”


Study Results
The combination of Imprime PGG with cetuximab and carboplatin/paclitaxel showed a substantial and statistically significant improvement in objective response rate (ORR) of 48% (p=0.048) in the Imprime PGG treated group compared to 23% in the control group. This improvement was even greater in the biomarker-positive subgroup, which had an ORR of 67% (p=0.009). Beneficial effects were observed in both squamous and non-squamous NSCLC patients. Among patients with squamous cell NSCLC, a cancer for which there few treatment options today, the ORR was 100% (N=6) for biomarker-positive Imprime PGG subjects compared with 30% (N=10) for control group subjects (p=0.01).


Biothera researchers discovered a predictive biomarker that identifies patients who are most likely to best respond to Imprime PGG, a patented, complex carbohydrate (a beta glucan) derived from the cell walls of a proprietary strain of yeast. The biomarker is a naturally occurring antibody to beta glucan that is required for binding Imprime PGG to neutrophils and monocytes, the largest population of immune cells in the body. When bound, Imprime PGG engages and directs these innate immune cells to recognize and kill antibody-targeted cancer cells. Using a serum-based assay, Biothera is able to identify biomarker-positive patients.


Although the study was not powered for Overall Survival, the results indicated a strong trend for improvement in the biomarker-positive subgroup as well. The Median Overall Survival for the biomarker-positive Imprime PGG-treated subgroup was 16.5 months compared with the control group of 11.2 months. Positive survival benefits were also observed in squamous cell as well as non-squamous cell NSCLC patients.


Imprime PGG was well tolerated, with adverse events consistent with toxicities attributable to the cytotoxic drugs or cetuximab alone.


“Numerous preclinical studies have demonstrated the effectiveness of the combination therapy of Imprime PGG and monoclonal antibodies in multiple tumor models. The current clinical data confirm the preclinical results and validate Biothera’s approach of modulating the innate immune system to fight virtually all types of cancer,” said Myra Patchen, Ph.D., chief scientific officer, Biothera’s Pharmaceutical Group. “The excitement about the biomarker is that it links directly to the mechanism of action of Imprime PGG and now we have clinical data supporting its use. This discovery will enable future clinical trials to be enriched for subjects most likely to respond to Imprime PGG.”


The title of AACR-IASLC poster presentation was “Imprime PGG improves the efficacy of carboplatin, paclitaxel and cetuximab chemoimmunotherapy of advanced non-small cell lung cancer (NSCLC).”


This study was conducted at 12 locations in the U.S. and Germany. This poster was authored by Michael Thomas M.D., Parvis Sadjadian M.D., Jens Kollmeier M.D., Zhonglin Hao M.D., Nandita Bose Ph.D., Mary Antonysamy Ph.D., Myra Patchen Ph.D., Jamie Lowe, Michelle Gargano, Richard D. Huhn M.D., Keith Gorden, Paulette Mattson, Folker Schneller M.D.


About Imprime PGG®

Imprime PGG is a novel immunomodulatory drug in development as a cancer therapy. Innate immune cells are the most abundant immune cells in the body and are normally responsible for pathogen killing, but not anti-tumor activity. However, Imprime PGG has been shown to bind to neutrophils and monocytes and redirect their killing ability to reduce tumor growth and enhance long-term survival. This targeted mechanism is synergistic with multiple anti-tumor monoclonal antibodies, providing the potential to improve patient outcomes in a wide range of cancer indications. Imprime PGG has demonstrated marked improvements in overall response rates in multiple clinical trials for colorectal cancer, KRAS-mutant colorectal cancer and chronic lymphocytic leukemia. Imprime PGG is currently in a Phase 3 clinical trial for advanced colorectal cancer and a Phase 2 NSCLC study with bevacizumab (Avastin®).


About Biothera, the Immune Health Company

Biothera is a U.S. biotechnology company dedicated to improving immune health. The company is developing pharmaceuticals that engage the innate immune system to fight cancer.


David Walsh
VP Communications
Biothera, the Immune Health Company
651-256-4606 (direct)


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