JNJ 28871063 hydrochloride

Revoking the privilege: targeting HER2 in the central nervous system.[Pubmed:17981994]

Mol Pharmacol. 2008 Feb;73(2):271-3.

Pharmacologic agents developed for cancer therapy have traditionally relied on a therapeutic ratio of effects between tumors and normal tissue. Over the past decade, this concept has been refined through the development of agents that are intended to specifically target tumor cells. The epidermal growth factor receptor (EGFR) (ErbB) family of receptor tyrosine kinases is an intensely studied target in many cancer cell types, and several successful therapeutic agents have been developed to block the growth promoting functions of these receptors. However, with their success has come the evolution of novel clinical scenarios by which tumor cells can evade these targeted therapies. Trastuzumab, a monoclonal antibody to Her2/ErbB2 that is used in breast cancer, has been shown to provide a survival benefit for patients whose tumors express this receptor but it does not have activity in the central nervous system because of the blood-brain barrier. In this issue of Molecular Pharmacology, Emanuel et al. (p. 328) report on a tyrosine kinase inhibitor that targets Her2/neu and also crosses the blood-brain barrier. Efforts to improve current strategies of targeting this receptor may lead not only to benefits in the treatment of breast cancer but also to advances in the treatment of other central nervous system malignancies, such as gliomas and medulloblastoma.

Cellular and in vivo activity of JNJ-28871063, a nonquinazoline pan-ErbB kinase inhibitor that crosses the blood-brain barrier and displays efficacy against intracranial tumors.[Pubmed:17975007]

Mol Pharmacol. 2008 Feb;73(2):338-48.

JNJ-28871063 is a potent and highly selective pan-ErbB kinase inhibitor from a novel aminopyrimidine oxime structural class that blocks the proliferation of epidermal growth factor receptor (EGFR; ErbB1)- and ErbB2-overexpressing cells but does not affect the growth of non-ErbB-overexpressing cells. Treatment of human cancer cells with JNJ-28871063 inhibited phosphorylation of functionally important tyrosine residues in both EGFR and ErbB2 and blocked downstream signal transduction pathways responsible for proliferation and survival. A single dose of compound reduced phosphorylation of ErbB2 receptors in tumor-bearing mice, demonstrating target suppression in vivo. Tissue distribution studies show that JNJ-28871063 crosses the blood-brain barrier and penetrates into tumors, where it is able to accumulate to higher levels than those found in the plasma. JNJ-28871063 showed oral antitumor activity in human tumor xenograft models that overexpress EGFR and ErbB2. In an intracranial ErbB2-overexpressing tumor model, JNJ-28871063 extended survival relative to untreated animals. The brain is a primary site of metastasis for EGFR-overexpressing lung cancers and ErbB2-overexpressing breast cancers. Therefore, the ability to penetrate into the brain could be an advantage over existing therapies such as trastuzumab (Herceptin) and cetuximab (Erbitux), which are antibodies and do not cross the blood-brain barrier. These results show that JNJ-28871063 is orally bioavailable, has activity against EGFR and ErbB2-dependent tumor xenografts, and can penetrate into the brain and inhibit ErbB2-overexpressing tumor growth.