First HDAC Inhibitor Approved by FDA to Treat Cutaneous Effects of CTCL

Merck & Co, Inc, recently announced that the Food and Drug Administration (FDA) has approved oral vorinostat (Zolinza), 400 mg once daily, for the treatment of cutaneous manifestations in patients with cutaneous T-cell lymphoma (CTCL), a form of non-Hodgkin's lymphoma, who have progressive, persistent, or recurrent disease on or following two systemic therapies. CTCL is a cancer of the T cells that affects the skin.

Mechanism of Action

Vorinostat is a histone deacetylase (HDAC) inhibitor. Based on in vitro studies, the drug inhibits the enzymatic activity of HDAC1, HDAC2, HDAC3 (class I), and HDAC 6 (class II) at nanomolar concentrations. In some cancer cells, excess amounts of the enzyme HDAC prevent the activation of genes that control normal cell activity. Vorinostat is believed to decrease the activity of HDAC, allowing for the activation of genes that may help to slow or stop the growth of cancer cells. The exact mechanism of the agent's anticancer effect has not been fully characterized.

"With today's FDA approval of Zolinza, there is now an effective new option in the fight against cutaneous manifestations of cutaneous T-cell lymphoma, specifically in patients who have tried and failed other cancer treatment options," said Elise Olsen, MD, director, CTCL Clinic & Research Center at Duke University Medical Center and lead investigator of one of the studies that led to the approval.