CRLX101 Rectal Cancer Data Presented at ASCO 2015 Gastrointestinal Cancers Symposium

Cerulean Pharma Inc. (Nasdaq: CERU), a leader in Dynamic Tumor Targeting™, today announced that preclinical data and initial clinical data from a Phase 1b/2 investigator-sponsored trial of CRLX101 in combination with chemoradiotherapy in non-metastatic rectal cancer was presented at the ASCO 2015 Gastrointestinal Cancers Symposium held January 15-17, 2015.

Andrew Wang, MD, Department of Radiation Oncology, UNC Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, the Principle Investigator on the trial, presented a poster entitled Improving neoadjuvant chemoradiotherapy for rectal cancer with CRLX101, a nanoparticle-drug conjugate, with a camptothecin payload.

“Our preclinical data strongly support adding CRLX101 to the standard of care, chemoradiotherapy, in the treatment of rectal cancer in the neoadjuvant setting,” said Dr. Wang. “For example, it is especially exciting to observe that CRLX101 is significantly more effective than oxaliplatin, a therapeutic that has been extensively studied, in our preclinical model of rectal cancer chemoradiation. In the preclinical models, the addition of oxaliplatin to 5FU and radiotherapy did not lead to significant tumor growth delay. In comparison, the addition of CRLX101 to 5FU and radiotherapy delayed the doubling of tumor volume from approximately 11 days (5FU + radiation) to 25 days (CRXL101 +5FU + radiation).”

The purpose of the ongoing clinical study is to evaluate CRLX101 in combination with chemoradiotherapy and to assess if the addition of CRLX101 to chemoradiotherapy can improve rectal cancer outcomes in the neoadjuvant setting. In the Phase 1b portion of the study, patients in the first cohort received chemoradiotherapy plus 12 mg/m2 of CRLX101 and patients in the second cohort received chemoradiotherapy plus 15 mg/m2 of CRLX101. No DLTs have been reported from either cohort, and 15 mg/m2 has been established as both the maximum tolerated dose and recommended Phase 2 dose of CRLX101 in combination with chemoradiotherapy.

Dr. Wang further commented, “We are encouraged that CRLX101 appears to combine well with chemoradiotherapy. Therefore, we are excited to move forward in the Phase 2 portion of our combination trial.”

About CRLX101

CRLX101 is a dynamically tumor-targeted nanoparticle-drug conjugate (NDC) designed to concentrate in tumors and slowly release its anti-cancer payload, camptothecin, inside tumor cells. CRLX101 inhibits topoisomerase 1 (topo 1), which is involved in cellular replication, and hypoxia-inducible factor-1α (HIF-1α), which research suggests is a master regulator of cancer cell survival mechanisms thought to promote drug and radiation resistance. CRLX101 has shown activity in four different tumor types, both as monotherapy and in combination with other cancer treatments. CRLX101 is currently in Phase 2 clinical development and has been dosed in more than 250 patients.

About CRLX301

CRLX301 is a dynamically tumor-targeted NDC designed to concentrate in tumors and slowly release its anti-cancer payload, docetaxel, inside tumor cells. In preclinical studies, CRLX301 delivers up to 10 times more docetaxel into tumors, compared to an equivalent milligram dose of commercially available docetaxel and was superior to docetaxel in seven of seven animal models, with a statistically significant survival benefit seen in five of those seven models. In addition, preclinical data show that CRLX301 had lower toxicity than has been reported with docetaxel in similar preclinical studies. CRLX301 is currently in Phase 1 clinical development.

About Cerulean’s Dynamic Tumor Targeting™ Platform

Cerulean’s Dynamic Tumor Targeting Platform creates NDCs that are designed to provide safer and more effective cancer treatments. We believe our NDCs concentrate their anti-cancer payloads inside tumors while sparing normal tissue because they are small enough to pass through the “leaky” vasculature present in tumors but are too large to pass through the wall of healthy blood vessels. Once inside tumors, our NDCs enter tumor cells where they slowly release anti-cancer payloads from within the tumor cells.

About Cerulean Pharma

The Cerulean team is committed to improving treatment for people living with cancer. We apply our Dynamic Tumor Targeting Platform to create a portfolio of NDCs designed to selectively attack tumor cells, reduce toxicity by sparing the body’s normal cells, and enable therapeutic combinations. Our first platform-generated candidate, CRLX101, is in multiple clinical trials in combination with other cancer treatments, all of which aim to unlock the power of combination therapy. Our second platform-generated candidate, CRLX301, is in a Phase 1/2a clinical trial. For more information, please visit www.ceruleanrx.com.

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