A blood test that can be used to identify patients eligible for treatment with AstraZeneca’s lung cancer drug Iressa has been recommended for approval in Europe.
The Committee for Medicinal Products for Human Use (CHMP) issued a positive opinion for the diagnostic test, which is a less-invasive alternative to the current tumour biopsy approach used to identify non-small cell lung cancer (NSCLC) patients who can benefit from Iressa (gefitinib).
Iressa’s highly-specific mechanism of action means it is only suitable to treat NSCLC patients who test positive for mutations in the epidermal growth factor receptor (EGFR) tyrosine kinase, but currently a quarter of patients do not have a biopsy available to guide treatment decisions.
With the treatment of cancer increasingly being driven by the genetic characteristics of tumours, companion diagnostics are becoming an important way for companies to differentiate their products from rivals in the marketplace.
That is particularly true in the first-line treatment of NSCLC, where Iressa is jostling for market share with a number of other EGFR tyrosine kinase inhibitors (TKIs) such as Roche/OSI’s Tarceva (erlotinib) and Boehringer Ingelheim’s recently approved Giotrif (afatinib).
The CHMP opinion means Iressa will be the first drug in the class in Europe “to have a label allowing the use of circulating tumour DNA (ctDNA) obtained from a blood sample,” said AZ in a statement.
The label change will take effect immediately and will be applicable in all 28 EU member states, added the company, which noted that the diagnostic was developed via a partnership with Qiagen. AstraZeneca is also working with Roche on a test for Iressa follow-up AZD9291, which has just begun phase III clinical studies in NSCLC.
Briggs Morrison, AZ’s chief medical officer, said: “Understanding the nature of an 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 treated.”
“If doctors are unable to assess the mutation status of a tumour, then patients’ access to potentially life-changing medicines such as Iressa becomes restricted,” he added.
Patients who have been treated with EGFR-TKIs in whom the disease has progressed have to undergo a repeat biopsy to see if they have the T790M mutation, so a blood test will help doctors make subsequent treatment decisions for patients more quickly.
Iressa is AZ’s second-biggest oncology product, bringing in $316m in sales in the first half of this year. Despite getting a little mature, the drug is also an important platform for AZ’s newer cancer drugs, including much anticipated anti-PD1 drug MEDI4736 with which it is being tested as a combination therapy.