Celera Genomics will develop CRA-024781, a novel histone deacetylase inhibitor, as a cancer drug, the company said this week. Along with the drug, the firm will develop biomarkers for use in monitoring patients taking the drug, Robert Booth, Celera Genomics chief scientific officer, told Pharmacogenomics Reporter this week.
Specifically, Celera has been concentrating on developing biomarkers for use in a pharmacodynamic readout. "We can use acetylated tubulin or histone to track, for example, how long we're inhibiting histone acetlyation in vivo in humans," said Booth. The company hopes that these biomarkers will "help [Celera's] clinical trials, and get the right dose in the right patient," he said.
Celera filed an investigational new drug application with the US Food and Drug Administration this week, and should its application require no changes, it will be free to begin clinical trials soon. "A university hospital" will be conducting the drug's trials for Celera, said Booth, but he declined to name the facility.
The company has "one or two" other proteins in its sights for use as efficacy biomarkers that may prove useful in monitoring treatment, said Booth. "We think we've identified certain novel entities that change after we treat cells with our compound," he said. But the company "isn't talking about those, because we believe it's going to provide us with a proprietary advantage," he said.
As for other biomarkers involved with the new drug, the company "has been working very hard … to identify the tumors that we can take the compound towards, and also the best patients that we should target," said Booth.
Celera has "some idea" which tumor types may be best suited to HDAC-inhibitor therapy, but the company considers that information confidential because drugs of the same class in other companies' pipelines may share some of the same properties, he said. "There are a number of tumors where clinical activity has been reported for other HDAC inhibitors, including renal cell, head and neck, and thyroid carcinoma," said Booth.
Other HDAC inhibitors currently in development include: Novartis' LAQ-824; Aton Pharmaceuticals' suberoylanilide hydroxamic acid, known as SAHA; Gloucester Pharmaceuticals' Depsipeptide; Curagen's PXD101; and Schering AG's MS-275.
Booth declined to estimate the size of the potential market in which the compound would play. There are no HDAC inhibitors on the market yet, he said.
The compound impacts a key gene-regulation change that cancer cells undergo. In tumor cells, histone acetylation seems to alter the transcriptional regulation of a subset of genes, a number of which "appear to be tumor-suppressor genes" that are thought to be associated with regulation of the cell cycle, cell division, and apoptosis, said Booth. In certain cancers, the activity of the HDAC enzyme is increased, compared to that found in normal tissues, said Booth. In animal and cell-culture studies, Celera's inhibitor causes the reactivation of some of those genes, some of which are tumor suppressors capable of forcing tumor cells into apoptosis, he added.
Histones are key proteins involved in DNA packaging, chromatin structure, and gene regulation.
Celera's other drug hopeful, the osteoporosis compound Cathepsin K, is currently in Phase I trials in partnership with Merck Pharmaceuticals. The company is also in preclinical development of a psoriasis drug and it is in the initial stages of the development of an immunosuppressive compound.