Enzon Pharmaceuticals Inc. presented data from its pipeline programs at the 2009 EORTC-NCI-AACR (European Organization for Research and Treatment of Cancer-National Cancer Institute-American Association for Cancer Research) annual meeting in Boston, Massachusetts. The Posters and Abstracts that were presented included: PEG-SN38 (EZN-2208); Phase 1, first-in-human, dose-escalation study of EZN-2208, a novel anticancer agent, in patients with advanced malignancies (Poster C216), EZN-2208, a novel agent, was well tolerated in previously treated patients with advanced malignancies. No cumulative toxicities were reported. The dose-limiting toxicity (DLT) for EZN-2208 administered as a 1-hour i.v. infusion every 3 weeks, with or without granulocyte colony-stimulating factor (G-CSF), was febrile neutropenia, contrasted with the DLT of irinotecan. The maximum-tolerated dose (MTD) and recommended Phase 2 dose of EZN-2208 administered once every 3 weeks is10 mg/m2 for EZN-2208 administered without G-CSF and 16.5 mg/m2 for EZN-2208 administered with G-CSF. Stable disease, sometimes prolonged and associated with tumor shrinkage, was observed as the best response. For some patients, the duration of EZN-2208 was longer than the duration of their prior therapy. EZN-2208, a novel anticancer agent, in patients with advanced malignancies: a Phase 1 dose-escalation study (Poster C221), EZN-2208, a novel agent, was well tolerated in previously treated patients with advanced malignancies. The DLT was neutropenia with or without fever, in distinction to the DLT of irinotecan. The MTD and recommended Phase 2 dose for EZN-2208 administered every 3 weeks is 9 mg/m2. Prolonged periods of stable disease, sometimes associated with tumor shrinkage, were observed. For some patients, the duration of EZN-2208 was longer than the duration of their prior therapy. EZN-2208 is being evaluated in a Phase 2 study in patients with metastatic colorectal cancer who failed prior oxaliplatin and irinotecan containing regimens (CRC). Survivin Antagonist (EZN-3042); EZN-3042, a novel survivin messenger ribonucleic acid (mRNA) antagonist, administered as a single agent or with docetaxel: results of a Phase 1, first-in-human, pharmacokinetic (PK), combination after single agent (CASA) dose-escalation study (Poster A99), EZN-3042 was generally well tolerated in previously treated patients with advanced malignancies. The DLT for single-agent EZN-3042 was increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT). For the EZN-3042 and docetaxel combination, one patient had a DLT of febrile neutropenia. Enrollment is ongoing. A qualitative assessment of the single-agent EZN-3042 pharmacokinetics (PK) data indicated that the concentration-time curve (AUC) and maximum plasma concentration (Cmax) appear to increase in a dose-proportional manner. The combination after single agent dose-escalation design is an innovative approach that allows one to follow the safety and efficacy of single-agent and combination therapy in the same patient. The beta-catenin antagonists (EZN-3889 and EZN-3892) potently and specifically inhibit the target mRNA expression both in vitro and in vivo. Targeted down-modulation of beta-catenin mRNA effectively leads to downregulation of beta-catenin protein expression and could lead to growth inhibition in beta-catenin-driven tumor cell lines. These novel agents specifically inhibit a transcription factor that has been difficult to target with conventional agents. LNA based RNA antagonist, when used in the high nanomolar, low micromolar range readily down modulate mRNA and protein of interests in multiple cell lines without any assistance. LNA oligonucleotide represents a promising option for rapid, simple, and specific determination of gene function, target validation, and identification of drug-sensitive tumors for further in vivo evaluation and furthermore is an attractive therapeutic strategy.

Enzon Pharmaceuticals Inc. reported unaudited consolidated earnings results for the third quarter ended September 30, 2009. For the quarter, the company has posted net income of $0.1 million or break-even on a diluted per-share basis, as compared to a net loss of $2.0 million or $0.05 on a diluted per-share basis for the third quarter of 2008. Total revenues were $44.60 million compared to $48.79 million for the same period a year ago. Operating income was $0.76 million compared to operating loss of $0.006 million for the same period a year ago. Loss before income tax was $0.65 million compared to $1.85 million for the same period a year ago. Adjusted net income was $0.13 million compared to $0.67 million or $0.01 per share for the same period a year ago.

Enzon Pharmaceuticals Inc., Q3 2009 Earnings Call, Nov-03 2009