S*BIO's Novel Dual mTOR/PI3 Kinase Inhibitor SB2343 Demonstrates Excellent PK/PD Properties Leading to Significant Anti-Tumor Efficacy in Xenograft Models

SINGAPORE, Feb. 28, 2011 /PRNewswire/ -- S*BIO Pte Ltd today announced that its novel dual mTOR/PI3 Kinase inhibitor SB2343 demonstrated excellent pharmacokinetic/pharmacodynamic (PK/PD) properties leading to significant anti-tumor efficacy in rapamycin-sensitive and resistant xenograft models. In vivo and in vitro data on SB2343 were presented at American Association of Cancer Research (AACR) Special Conference on Targeting PI3K/mTOR Signaling in Cancer held in San Francisco.

SB2343 is a uniquely selective and orally active mTOR/PI3 Kinase inhibitor that targets the PI3K signalling pathway with high and equivalent potency against both mTOR and PI3K enzymes.  The combined modulation of these two kinases with SB2343 provides an attractive and powerful therapeutic approach for the treatment of patients with a wide range of cancers alone or in combination.

"The pre-clinical data for our mTOR/PI3K inhibitor SB2343 strongly demonstrate its unique treatment potential in a broad range of cancers that are dependent on elevated PI3K signalling," said Jan-Anders Karlsson, CEO of S*BIO. "The advancement of our diversified pipeline shows our continued commitment to develop high quality products in the oncology area."

Abstracts:

Poster Session A (Friday, February 25th)

SB2343, a novel tetra-substituted purine, inhibits mTOR and PI3K equipotently, has favorable pharmacokinetic and pharmacodynamic properties and is orally efficacious in various cancer models

SB2343 is a potent dual mTOR/PI3K inhibitor with excellent pharmaceutical and pharmacodynamic properties, tolerability and anti-tumor efficacy.  SB2343 has therapeutic potential for the treatment of a broad range of Rapamycin-sensitive, but also – resistant cancers. Efficacious doses of SB2343 were selected after pharmacokinetic and biomarker analysis of PC3 tumor-bearing mice, treated with single oral doses.  Anti-tumor efficacy of SB2343 was evaluated in mouse xenograft models following once per day oral dosing.

Poster Session B (Saturday, February 26th)

A novel series of tetra-substituted purines potently inhibit mTOR and PI3K, exhibit striking selectivity and demonstrate good pathway inhibition in vivo

Following structure activity relationship (SAR) investigations, SB2343 was selected for testing in vivo. A single dose of 25 mg/kg of SB2343 resulted in efficient and sustained inhibition of phosphorylation of Akt and S6 in tumor tissues. Lead optimization has resulted in the selection of SB2343 as a potent and selective orally bioavailable mTOR and pan-PI3 kinase inhibitor.

About S*BIO Pte Ltd

S*BIO is a privately-held biotech company focused on the research and clinical development of novel targeted small molecule drugs for the treatment of cancer with leading programs around histone deacetylases (HDAC) and kinases. S*BIO's HDAC inhibitor, SB939, is currently in Phase 2 trials. SB1518, S*BIO's potent and orally-active JAK2 inhibitor, entered the clinic in 2008 and is now completing Phase 2 trials.  It has received orphan drug designation from the U.S. and the E.U. regulatory authorities. S*BIO has entered into a development collaboration, and option & license agreement with Onyx Pharmaceuticals, Inc. to develop and commercialize SB1518 and its other novel JAK2 inhibitor, SB1578 in North America and Europe. S*BIO's SB1317, a novel multikinase inhibitor, is in Phase 1 trials and under a worldwide exclusive license with Tragara Pharmaceuticals, Inc. for its development and commercialization.

In line with its vision to be a leading fully-integrated oncology-focused biotech company in Asia Pacific, S*BIO has established a state-of-the-art R&D infrastructure, complemented by a strong clinical development team. S*BIO has strong links with a network of medical oncologists in Asia Pacific and its investors include Bio*One Capital a subsidiary of EDBI (EDB Investments), Aravis Ventures, Mitsui Ventures, Novartis Bioventures and other international funds. In 2009, S*BIO received the BioSpectrum Editor's Choice, Emerging BioScience Company of Singapore Award. More information about S*BIO can be found at www.sbio.com.

SOURCE S*BIO Pte Ltd