BTP-277 has evolved to become PEN-221, embodying the miniaturized biologic drug conjugate targeting the somatostatin receptor, but no longer encapsulated in a nanoparticle.

Blend Therapeutics Presents Preclinical Data for Lead Pentarin™ Program, BTP-277, Demonstrating Specific and Potent Tumor Cell Targeting for Small-Cell Lung Cancer

First Product from The Pentarin™ Platform, A Novel Class of Miniaturized Biologic Drug Conjugates (mBDCs) Incorporated in Nanoparticles

Data Presented at AACR Annual Meeting

WATERTOWN, MA – April 21, 2015 – Blend Therapeutics, Inc., a biopharmaceutical company discovering and developing two distinct classes of targeted anti-cancer medicines to advance the treatment of patients with solid tumor cancers, presented preclinical data today on its lead Pentarin™ program, BTP-277, showing specific and potent targeting of tumor cells expressing the somatostatin receptor, which is known to be over expressed in small cell lung cancer (SCLC) and neuroendocrine cancer tumor cells.  BTP-277 is the first in a series of proprietary drug candidates from Blend’s Pentarin™ platform, which creates miniaturized biologic drug conjugates (mBDCs) incorporated in polymeric nanoparticles that offer the potential for highly effective penetration and distribution of targeted anti-cancer treatment deep into the tumor tissue. The results were presented in a poster entitled “Pentarins: Improved tumor targeting through nanoparticle encapsulation of miniaturized biologic drug conjugates” at the American Association for Cancer Research (AACR) Annual Meeting in Philadelphia, Penn. 

BTP-277’s biologic targeting ligand is designed to specifically and selectively target cancers that over-express the somatostatin receptor.  The targeting ligand is conjugated to a potent cytotoxic payload through an optimized chemical linker to create miniaturized biologic drug conjugates (mBDCs), which are incorporated in nanoparticles to create the Pentarin, BTP-277.  Synergistic anticancer activity occurs based on the unique approach of the Pentarin:  the nanoparticle enables high therapeutic concentration of mBDCs in the tumor; the small size of mBDCs allows for effective penetration deep into the tumor tissue; and ligand’s targeting ability allows for specific binding to tumor cells and selective intracellular payload delivery. 

“Pentarins are novel biologic drug conjugates specifically designed for solid tumors, with a unique structure, miniaturization and nanoparticle combination designed to enable the selective targeting of cancer cells and impressive penetration deep into tumor tissue. Our approach represents a significant advance in the field since the first development of antibody drug conjugates 35 years ago and other medicines designed for the treatment of solid tumor cancers,” said Richard Wooster, PhD, President of Research and Development of Blend.  “Our most advanced Pentarin, BTP-277, has shown the ability to specifically and potently target small cell lung cancer tumor cells, providing highly encouraging results for the superior potential of a Pentarin. We expect BTP-277 to have a similar effect in additional somatostatin receptor over-expressing tumors.  We are on track to complete the studies necessary to advance our first Pentarin into clinical trials in early 2016 to prove its potential to meet the unmet needs of cancer patients.”

The data presentation at AACR describes that the Pentarin from the BTP-277 program resulted in complete tumor regressions in small cell lung cancer tumors with no tumors reappearing by the end of the study at 103 days.  In contrast, the miniaturized biologic drug conjugate (mBDC) alone – without the additional Pentarin components – resulted initially in shrinkage of tumors which then regrew. The mBDC in the BTP-277 Pentarin showed high affinity for the somatostatin receptor and was rapidly internalized into somatostatin over-expressing tumor cells where the potent cytotoxic payload exerted its cell killing effects. BTP-277 resulted in a 10-fold increase in total plasma levels and detectable levels in plasma 24 hours after dosing. In contrast, the mBDC alone was undetectable in plasma two hours after dosing.  

About Pentarins™
Pentarins represent a novel approach for the application of biologic drug conjugates to the treatment of cancer.  Pentarins are comprised of a miniaturized biologic drug conjugate (mBDC) in a polymeric nanoparticle. Blend applies its proprietary suite of technologies to create novel mBDCs comprised of a proprietary targeting ligand conjugated to a potent cell-killing agent through a chemical linker.  The mBDCs are incorporated in polymeric nanoparticles to protect them from their rapid clearance and allow for their accumulation in the tumor. Pentarins are designed to overcome the biological barriers that limit therapeutic effectiveness against solid tumors. Together, the components of Blend’s proprietary Pentarins have distinct yet synergistic anticancer capabilities: the nanoparticle enables high therapeutic concentration at the tumor site, the small size of mBDCs allows for effective penetration and distribution deep into the tumor tissue, the ligand’s targeting ability allows for specific binding to tumor cells, and the cell-killing payload is released inside the cancer cells. 

About Blend Therapeutics
Blend Therapeutics, Inc., is a biopharmaceutical company discovering and developing two distinct classes of targeted anti-cancer medicines to advance the treatment of patients with solid tumor cancers. Blend’s pipeline includes its lead drug candidate, BTP-114, a novel, personalized cisplatin prodrug derived from the company’s R&D heritage in platinum drugs, as well as BTP-277 and other novel drug conjugates from the company’s proprietary Pentarin™ platform.  Blend’s first Pentarin drug candidate, BTP-277, represents the proprietary components of Blend’s miniaturized biologic drug conjugate (mBDC) technology – a novel targeting ligand conjugated to a potent cell-killing agent with a chemical linker – incorporated into nanoparticles to enable the penetration of the conjugates deep in to the tumor tissue where they selectively bind to tumor cells.  Blend’s strategy includes developing its own proprietary Pentarins as well as applying the Pentarin platform to enhance the therapeutic capabilities of the targeting protein scaffolds or payloads of pharmaceutical collaborators. 

The company was founded by three leaders in the fields of chemistry and nanomedicine from the Brigham and Women’s Hospital (BWH)–Harvard Medical School (HMS), and Massachusetts Institute of Technology (MIT): Dr. Omid Farokhzad of BWH–HMS, and Dr. Robert Langer and Dr. Stephen J. Lippard of MIT. Blend has attracted top-tier investors including Eminent Venture Capital, Flagship Ventures, NanoDimension, and New Enterprise Associates.

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Media Contact:
Kathryn Morris
The Yates Network