AstraZeneca has collaborated with Roche to develop a plasma-based companion diagnostic test to support AZD9291, AstraZeneca’s investigational compound in clinical development for the treatment of non-small-cell lung cancer (NSCLC).

AstraZeneca R&D facility

The test is designed to identify epidermal growth factor receptor (EGFR) mutations in both tumor tissue and plasma derived from patients with NSCLC as well as to optimize the clinical development of AZD9291 for patients who are resistant to first-generation EGFR tyrosine kinase inhibitors (TKI).

Patients who have been treated with EGFR-TKIs in whom the disease has progressed, have to undergo a repeat biopsy to evaluate whether they have a specific mutation, T790M.

The company said that based on circulating DNA (ctDNA) in plasma samples, diagnostic tests offer an alternative method of identifying the T790M mutation.

AstraZeneca Global Product Strategy for Oncology senior vice-president Mondher Mahjoubi said the company is committed to developing targeted medicines that improve health outcomes for patients.

"Understanding the nature of each individual’s tumour and therefore which medicine is most likely to benefit them is vital if we are to transform the way cancer patients are diagnosed and treated," Mahjoubi said.

Roche Molecular Diagnostics (RMD) head Paul Brown said currently, late-stage lung cancer patients have to undergo surgery to collect tissue from a tumor so it can be sent for molecular testing.

"In some cases, collecting enough tissue for testing is not possible. This collaboration will enable molecular testing through plasma specimens and provide the information needed to inform treatment decisions without the complications of surgery, consequently increasing the level of care clinicians can give to the patient," Brown said.

AZD9291 is an irreversible inhibitor of both the activating sensitising EGFR mutation (EGFRm+) and the activating resistance mutation, T790M, while sparing the activity of wild type EGFR.

Image: AstraZeneca’s R&D Site in Mölndal, Sweden. Photo: courtesy of Erik031