Natera has begun the subject enrolment in the randomised Phase III SAGITTARIUS clinical trial designed to assess the Signatera test in determining personalised adjuvant treatment strategies for individuals with stage III and high-risk stage II colon cancer post-surgical resection.

Funding for the trial is provided by the European Union Horizon Europe Programme and was sponsored by The AIRC Institute of Molecular Oncology (IFOM-ETS).

Nearly 700 to 900 subjects will be recruited in the trial. Those who test positive for Signatera will be selected to receive either genotype-guided therapy customised to their tumour mutational profile or standard chemotherapy for six months.

The investigational arm of the trial will consider the use of immunotherapy or targeted agents, typically used for metastatic colon cancer, to potentially increase cure rates with adjuvant therapy. This approach will be based on various genomic factors including mismatch repair and RAS/RAF mutation status.

For negative-tested subjects, the study will explore the possibility of de-escalating treatment to either observation or a six-month course of single-agent capecitabine.

Natera oncology senior medical director Adham Jurdi said: “The trial aims to move beyond the traditional one-size-fits-all, post-surgical standard of care with chemotherapy by introducing a truly personalised treatment approach tailored to each patient.

“Signatera-positive patients will receive adjuvant therapies matched to their specific mutational profiles. Additionally, we are optimistic that the study will generate evidence to support the de-escalation of chemotherapy for Signatera-negative patients.”

The global trial involves 26 clinical centres across Spain, Germany, and Italy, and has collaborated with nine partners in five European countries.

It is part of the broader SAGITTARIUS project, which also comprises research on health costs and quality of life to comprehensively assess the cost-effectiveness of an interventional liquid biopsy.

The tumour-informed molecular residual disease test, Signatera uses circulating tumour DNA for identifying and quantifying residual cancer. It aims to detect recurrence earlier than conventional tools.