Oncologist optimistic about drug trial

Well-known oncologist Dr Dennis Slamon says he is “widely enthusiastic” about the results of a drug trial carried out in Ireland on women with the most common form of breast cancer.

Almost two-thirds of all women with breast cancer have the hormone receptor positive type of the disease. Many get a recurrence shortly after initial treatment.

Clinical trials carried out by the Irish Co-operative Oncology Research Group found that a new treatment dramatically extends the period between recurrences.

The new treatment, known as CDK46 (Cyclin-Dependent Kinase 4 and 6 Inhibitor), blocks the pathway of two proteins CDK4 and CDK6, which cause cancer cells to grow out of control.

In the control arm, women who are not receiving the treatment have a recurrence after 7½ months.

With the CDK46 drug, that timeframe extends to at least 26 months, and maybe longer, as the trial is ongoing.

Dr Slamon was in Dublin last week to catch up on the work of the research group. He received an honorary fellowship from the Royal College of Physicians in Ireland.

He discovered the drug Herceptin, which is applicable to women with the HER2 positive type of the disease, between 20 and 25 per cent of the women involved.

The new research was presented recently by Dr Slamon and his Irish collaborator, Prof John Crown. Dr Slamon described treatments for hormone receptor positive disease as the “biggest piece of the breast cancer challenge”.

The drug is now moving to bigger trials in Ireland and elsewhere in the hope it will be approved by the regulator. “We had hoped the news would be positive, but we are widely enthusiastic about how positive it was,” he said.

“It means the continuation of new therapies are more effective and less toxic. CDK46 opens a whole new avenue for women with breast cancer who haven’t been cured by their initial treatment,” he said.