Acceleron and Collaborators Present Data on Potential Biomarkers for Metastatic Breast Cancer and Head and Neck Cancer at the "2012 Markers in Cancer" Conference

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Acceleron Pharma, Inc., a biopharmaceutical company developing protein therapeutics for cancer and orphan diseases, and its collaborators are presenting data at the 2012 Markers in Cancer Conference in Hollywood, Fla., a joint meeting sponsored by ASCO, EORTC, and the NCI, that illustrate possible new biomarkers for use in metastatic breast cancer and in squamous cell carcinoma of the head and neck. The two poster presentations describe the potential role of activin A as an adverse biomarker for patients with metastatic breast cancer and of BMP9 as a biomarker for the identification and selection of patients with head and neck cancer. Acceleron is focused on developing novel medicines that regulate members of TGF-β superfamily of proteins, which include BMP9 and activin A. These proteins play fundamental roles in regulating the growth and differentiation of various cell types and are involved in diseases such as cancer.

Activin A in Metastatic Breast Cancer

• About half of HER2-positive metastatic breast cancer patients will respond to first-line trastuzumab-containing therapy, but most will progress within a year.
• Resistance to trastuzumab, commonly known by its brand name Herceptin®, remains a vexing clinical problem and better predictive and prognostic biomarkers are still needed.
• Allan Lipton, M.D., Professor at the Penn State Milton S. Hershey College of Medicine, and colleagues analyzed pretreatment levels of serum activin A in 60 metastatic breast cancer patients prior to initiation of first-line trastuzumab-containing therapy.
• Elevated pretreatment serum activin A levels were correlated with reduced progression free survival and overall survival and patients with persistently high activin A levels had significantly worsened outcomes compared to those with low activin A levels.
• Acceleron and Celgene are collaborating to discover and develop products that target activin A.
• Lindsey M. Zubritsky, of Penn State Hershey College of Medicine, will present the data during the general poster session on “Clinical Evaluation of Biomarkers” on October 11, 2012 at 5:30pm.

Study description and results:

Serum activin A was measured in 60 metastatic breast cancer patients before starting first-line trastuzumab-containing therapy. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox modeling with both continuous and dichotomous (median) serum activin A analyses. Higher serum activin A was significant on a continuous basis for predicting reduced PFS to first-line trastuzumab-containing therapy (p<0.003), and for predicting shorter OS (p<0.0001). When analyzed using a dichotomous (median) cutpoint, the elevated serum activin A cohort had a significantly reduced PFS (HR 2.79, p <0. 002) (median 6.6 mos vs.31.1 mos) and OS (HR 5.24, p <0.0001) (median 19.6 mos vs. median not reached). In multivariate analysis for PFS with other covariates (age, line of therapy, CA 15-3, and hormone receptor status), activin A was the only significant covariate (p=0.021). In multivariate analysis for OS, activin A (p=0.002) and CA 15-3 (p=0.03) remained significant as prognostic factors.

BMP9 in Head and Neck Cancer

• The National Cancer Institute estimates that over 47,000 patients will be diagnosed with squamous cell carcinoma of the head and neck in the United States in 2012.
• Head and neck cancer remains a clinically challenging disease, and with only one new drug therapy approved in the past 50 years, the prognosis for patients with recurrent or metastatic disease remains poor.
• Scott Pearsall, Ph.D, from Acceleron, will present data showing elevated expression of bone morphogenetic protein (BMP9) in tumor samples from patients with squamous cell carcinoma of the head and neck (SCCHN), and the potential role for BMP9 as a biomarker for selecting patients who might benefit from treatment with the investigational drug dalantercept – Acceleron’s Phase 2 activin receptor-like kinase 1 (ALK1) inhibitor formerly known as ACE-041.
• The data will be presented during the general poster session on “Cell Signaling Pathways” on October 12, 2012 at 4:30pm.

BMP9 is a ligand that binds with high affinity to activin receptor-like kinase 1 (ALK1) and regulates the maturation stage of angiogenesis. In an analysis of archived tumor samples from patients with squamous cell carcinoma of the head and neck, 79% of the samples had either medium or high expression of BMP9. Dalantercept is an ALK1 receptor fusion protein that binds to BMP9 and BMP10 and inhibits their signaling through the ALK1 receptor. Dalantercept is currently in a Phase 2 clinical trial for treatment of patients with SCCHN (clinicaltrials.gov identifier: NCT01458392).

About Acceleron

Acceleron is a privately-held biopharmaceutical company committed to discover, develop, manufacture and commercialize novel protein therapeutics for orphan diseases and cancer. Acceleron’s scientific approach takes advantage of its unique insight to discover first-in-class therapies based on the TGF-β protein superfamily. Acceleron utilizes proven biotherapeutic technologies and capitalizes on the company’s internal GMP manufacturing capability to advance its therapeutic programs rapidly and efficiently. The investors in Acceleron include Advanced Technology Ventures, Alkermes, Avalon Ventures, Bessemer Ventures, Celgene, Flagship Ventures, MPM BioEquities, OrbiMed Advisors, Polaris Ventures, QVT Financial, Sutter Hill Ventures and Venrock. For further information on Acceleron, please visit www.acceleronpharma.com.