CuraGen Corporation and TopoTarget have initiated patient dosing in a phase II clinical trial evaluating the activity of PXD101, a small molecule histone deacetylase inhibitor, for the therapy of a type of cancer called mesothelioma.

Mesothelioma is a type of cancer arising from the cells, known as mesothelium, with the majority of cancers beginning in the chest cavity. The occurence rate of mesothelioma increases with age and is rarely diagnosed in patients under 55 years old. Exposure to asbestos is thought to bethe main cause of the disease.

National Cancer Institute is sponsoring the current clinical trial with CuraGen. Those who are having a diagnosis of mesothelioma, which is not removable by surgery and who have failed at least one line of chemotherapy are eligible for the clinical trial. The drug PXD101 is given by intravenous infusion once every three weeks.

The researchers are trying to determine if the drug PXD101 has any significant activity on mesothelioma in terms of clinical response. The study is also aimed at determining the safety of the drug and time to treatment failure. The study would also look for any survival advantage resulting from the use of the drug.

Researchers are planning to enroll a total of 37 patients at different sites across the United States.

Histone deacetylase inhibitors have the ability to down-regulate genes such as BCL-XL and VEGF and up-regulate cell-cycle regulating genes, including p21. Researchers say that they are excited to begin the trial and would evaluate PXD101 as a potential treatment for mesothelioma.

Sadly, there are no proven therapies available for patients who have progressed on the first line chemotherapy. PXD101 is expected to take this vacant position in the treatment algorithm.

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