Genzyme Corporation launches new test to monitor drug resistance in chronic myeloid leukaemia (CML) patients who are treated with Gleevec (imatinib mesylate).

Mutation analysis test will assist physicians in evaluating resistance to therapy and facilitate appropriate adjustments to treatment, claims the company release.

The molecular hallmark of CML is a mutation known as BCR-ABL. This mutation is the specific target for Gleevec and is found in 95 percent of patients with CML. In relapse patients, the majority of secondary mutations in the ABL portion of the gene correlate with treatment failure. Genzyme's new test detects all secondary BCR-ABL mutations and therefore predicts resistance to Gleevec.

"This is a very exciting time for leukaemia patients and their caregivers because this test will provide them with more information about their disease and will give them the ability to personalize their treatment," said Mara Aspinall, president of Genzyme Genetics, the business unit of Genzyme Corporation

"We are pleased to offer another important predictive test that can play a critical role in the way oncologists and patients manage their cancer," she added.

Genzyme recently launched several other personalised medicine tests in the areas of lung cancer and leukaemia and lymphoma.

Because of its high efficacy and limited side effects, Gleevec as a first-line therapy is considered to have revolutionised long-term survival of patients with CML. Gleevec was approved by the US Food and Drug Administration in May, 2001 as the first drug in a new class of molecular targeted therapies for CML.

Over 90 per cent of patients treated with Gleevec respond initially to treatment, and many experience a complete remission. However, four to five per cent of these patients eventually develop resistance to the treatment and experience a relapse of their disease, informed the release.

The discovery of the BCR-ABL mutations was made by researchers at the University of California at Los Angeles (UCLA) Jonsson Cancer Centre in 2001, who are currently working to determine if the same mutations in patients with CML may also lead to resistance to newer investigational treatments.

In October, Genzyme entered into a license agreement with UCLA to obtain exclusive, worldwide diagnostic rights to UCLA's discovery of gene mutations believed to be associated with drug resistance to Gleevec.

Chronic myeloid leukaemia is also known as chronic myelogenous leukaemia. According to the American Cancer Society, CML is a type of cancer that starts in blood-forming cells of the bone marrow and then invades the blood. It can spread to the lymph nodes, spleen, liver, and other parts of the body. CML can also change into a fast-growing acute leukemia that invades almost any organ in the body.

The American Cancer Society estimated that there were approximately 4,600 new cases of CML diagnosed in 2005. Approximately 25,000 CML patients are living in remission on therapy in the US today. The average age of people with CML is around 50 years.