The CDK 4/6 inhibitor, palbociclib, is Pfizer’s successful targeted therapy prescribed to more than 160 000 women with metastatic breast cancer around the world. The CDK 4/6 inhibitors, a class of targeted cancer therapies, interfere and target processes in the cells which cause cancer to grow. At present, no biomarkers are clinically in routine use to evaluate or monitor the efficacy of this class of targeted breast cancer drugs.

“This study provides evidence that DiviTum can be used to evaluate the efficacy of palbociclib in metastatic breast cancer. The results are encouraging in terms of clinical value. Via a blood test we can considerably improve our understanding when to use these new drugs and which patients should be selected for therapy for optimal outcome for each patient”, says Dr Luca Malorni, Prato Hospital, Italy.

The study evaluated blood samples from 45 women with metastatic breast cancer treated with palbociclib with or without standard therapy. Those patients with low DiviTumÒ values before start of treatment had longer time to progression than those patients with high levels. Patients with increasing DiviTumÒ values during palbociclib therapy had a median time to progression of 3.1 months compared to patients with decreasing levels who experienced 9 months before disease progression. Hence, change in TK levels during treatment provides important information for assessing treatment response.

“For patients with metastatic breast cancer, we now have clinical evidence that DiviTum® can be used to evaluate the treatment efficacy of a CDK 4/6 inhibitor. It is a milestone presenting these results addressing clinical efficacy of CDK 4/6 inhibitors from our ongoing trial program. We look forward to an exciting year, preparing our DiviTum® FDA application,” says Anders Rylander, CEO, Biovica International AB.

Reference: https://www.abstractsonline.com/pp8/#!/6812/presentation/5910 

DiviTum®

DiviTum® is an innovative biomarker assay developed with the aim to monitor and predict treatment response in cancer therapy. Via a blood sample, the test measures the activity of the enzyme thymidine kinase (TK). In normal cells, TK activity is hardly detectable, but in proliferating cells, the levels increase. Since the degree of TK activity is highly associated with the rate of cell proliferation, it is a particularly suitable biomarker for measuring tumor aggressiveness. DiviTum has in several trials already successfully demonstrated clinical potential in evaluating and monitoring the efficacy of endocrine standard treatments for women with metastatic breast cancer.