Zila awarded blocking patent for oral cancer test:

The US Patent and Trademark Office has granted Phoenix, Arizona-based Zila a patent covering the use of oxadine and thiazine dyes for detecting oral cancer by direct application to oral tissues. The company is developing OraTest, an oral rinse containing the dye toluidine blue for the detection of cancerous mouth lesions, but has had difficulty getting the product approved by the FDA (see Clinica No 842, p 13). The new patent will prevent other companies from developing a similar product using a dye from the same or comparable chemical family.