NEW YORK – Natera said Thursday that its Signatera circulating tumor DNA minimal residual disease (MRD) test will be used to guide patient selection and assess disease recurrence in the Phase II DECIPHER trial.
DECIPHER is a single-arm, open-label Phase II trial evaluating the efficacy of AstraZeneca and Daiichi Sankyo's Enhertu (trastuzumab deruxtecan), a HER2-directed antibody-drug conjugate in gastroesophageal adenocarcinoma (EGC) patients in the adjuvant setting.
The study aims to enroll up to 25 participants with pathologically documented adenocarcinoma of the stomach, gastroesophageal junction, or esophagus, and with HER2 overexpression, across 10 sites in the UK.
Patients who are Signatera-positive following neoadjuvant chemotherapy and surgery will receive up to eight cycles of Enhertu in place of standard-of-care adjuvant chemotherapy.
Thereafter, Signatera will be used to serially assess MRD as the trial's primary endpoint following surgery.
DECIPHER builds on data from the PLAGAST study, which showed that EGC patients who remained Signatera-positive after neoadjuvant FLOT (fluorouracil, leucovorin, oxaliplatin and docetaxel) chemotherapy and surgery had a higher risk of disease progression by 12 months, despite standard-of-care adjuvant treatment. These patients also showed a two-year overall survival rate of zero.
"With an adaptive approach aimed at eliminating MRD, DECIPHER is designed to offer patients a second chance at a cure when they have not responded to standard-of-care therapies," Elizabeth Smyth, a medical oncology consultant at Oxford University Hospitals NHS Foundation Trust l and chief investigator of the trial, said in a statement.
Adham Jurdi, senior medical director of oncology at Natera, added that "with DECIPHER, we aim to demonstrate how the pairing of Signatera with innovative therapies can potentially enable new personalized treatment options and ultimately improve outcomes for EGC patients."
The US Food and Drug Administration approved Enhertu last year for patients with metastatic breast cancer who have low HER2-expressing tumors.