Sweden-based biomarker assays developer Biovica has reported positive results from a clinical study of its DiviTum assay used to assess the biologic activity of Pfizer’s breast cancer drug palbociclib (Ibrance).
DiviTum is designed to predict and monitor treatment response in patients with cancer by measuring enzyme thymidine kinase (TK) activity in blood serum or cell cultures.
The study results showed that the new assay can evaluate the activity within two weeks and the shortened response evaluation window is expected to improve patient outcomes and their quality of life.
Carried out by researchers at the Washington University, St Louis, US, the study included 50 breast cancer patients who were administered with Ibrance and standard endocrine therapy combination before surgery.
Using the assay, cell proliferation rate was measured in blood samples that were obtained before and after two weeks of treatment.
DiviTum is reported to have successfully identified each patient’s anti-proliferative effect of Ibrance, resulting in the conclusion that the assay could be clinically useful for the prediction of treatment response to CDK 4/6 inhibitors such as the drug.
Washington University School of Medicine associate professor Dr Cynthia Ma said: “Our study provides the first clinical evidence of using DiviTum for measuring TK1 activity for early evaluation of the effect of palbociclib treatment in breast cancer.
“The results are very promising and support future studies of DiviTum to evaluate and identify patients for response to CDK 4/6 inhibitors.”
As all patients are unlikely to benefit from the CDK 4/6 inhibitor therapy, the assay is expected to save them from unwanted side effects and costs.
Biovica CEO Anders Rylander said: “CDK 4/6 inhibitors are very effective, but also costly and far from all patients respond.
“These results support our aim to provide DiviTum as a standard tool for evaluating treatments in metastatic breast and other cancers.”