CytRx Corporation a biopharmaceutical company specializing in oncology, announced that results from a series of preclinical studies show that bafetinib may be useful in preventing bone loss in cancer patients who are at high risk for this event. The studies, which evaluated the effect of bafetinib on bone cells (osteoclasts) from multiple myeloma patients, were directed by leading multiple myeloma expert James R. Berenson, MD, medical & scientific director of the Institute for Myeloma & Bone Cancer Research.

The studies demonstrated that in two model systems, bafetinib significantly suppressed the activity of osteoclasts and inhibited bone resorption in a dose-dependent manner, which is the process by which bone cells known as osteoclasts break down bone. Bone formation and bone resorption are closely coupled processes involved in the normal remodelling of bone. In patients with bone metastases, increased bone resorption can outpace bone remodelling, causing bone deterioration.

Dr Berenson stated, “The consequences of bone loss in cancer patients due to increased bone resorption can be devastating, including fractures, bone pain and hypercalcemia. Prior studies indicated that Lyn and Fyn kinases have negative impacts on osteoclasts, thus potentially reducing bone resorption, which prompted us to evaluate bafetinib's osteoclast inhibitory activity in bone deterioration using cells from multiple myeloma patients. We are encouraged by the results.”

CytRx president and CEO Steven A. Kriegsman said, “Results from these first-ever studies evaluating bafetinib's anti-bone resorptive effects showed that this kinase inhibitor could present a new therapeutic option to reduce skeletal complications in cancer patients. Reduction of bone loss represents one of multiple oncology indications in which bafetinib could represent an effective treatment.”

CytRx is currently evaluating bafetinib in three ongoing clinical trials: the Proact phase II proof-of-concept prostate cancer clinical trial in patients with advanced cancers; the Enable phase II proof-of-concept clinical trial in patients with a late-stage form of leukaemia known as high-risk B-cell chronic lymphocytic leukaemia; and a pharmacokinetic clinical trial in patients with recurrent brain tumours.

CytRx holds rights to bafetinib (formerly known as INNO-406) in all territories except Japan. Bafetinib is a potent, orally available, rationally designed, dual Bcr-Abl and Lyn kinase inhibitor, which was developed as a third-line treatment for patients with CML and certain forms of Acute Myeloid Leukaemia (AML) that are refractory or intolerant of other approved treatments.

In November 2008, CytRx announced that bafetinib demonstrated clinical responses in patients with CML in an international, open-label phase I dose-ranging clinical trial conducted in patients with CML and other leukaemia’s that have a certain mutation called the Philadelphia Chromosome (Ph+) and are intolerant of or resistant to Gleevec and, in some cases, second-line tyrosine kinase inhibitors such as dasatinib and nilotinib. In April 2010, the Company announced that bafetinib had received official notification from the Committee for Orphan Medicinal Products (COMP) of the European Medicines Agency (EMEA) that a positive opinion was made regarding the application for orphan medicinal product status for the treatment of Chronic Myeloid Leukaemia (CML). Bafetinib also has been granted Orphan Drug Status for the treatment of Philadelphia chromosome-positive (Ph+) CML by the US Food and Drug Administration (FDA).

CytRx Corporation is a biopharmaceutical research and development oncology company engaged in the development of high-value human therapeutics. The CytRx oncology pipeline includes three programmes in clinical development for cancer indications: bafetinib, tamibarotene and INNO-206.