AstraZeneca’s imminent announcement of overall survival (OS) data of Tagrisso (ingredient: osimertinib) at the upcoming oncology meeting in Europe is drawing keen attention. Depending on the results, scholars may start arguing over the treatment strategies using epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs).
AstraZeneca said it would release new data from the phase-3 FLAURA trial on Tagrisso -- a third-generation EGFR TIK -- at the European Society for Medical Oncology (ESMO) Congress in Barcelona, Spain, from Sept. 27 to Oct. 1.
The LAURA study compared the safety and efficacy of Tagrisso with conventional standard treatments Tarceva (erlotinib) or Iressa (gefitinib) in patients with EGFR-mutated non-small cell lung cancer (NSCLC).
|AstraZeneca’s treatment for non-small cell lung cancer Tagrisso
In August, AstraZeneca unveiled the topline results that showed Tagrisso’s OS improvement.
Once Tagrisso’s OS results of the first-line treatment are out at ESMO 2019, the Korean medical community is also likely to discuss when to use Tagrisso in “consecutive treatments.”
“Tagrisso can raise the quality of life for patients and is relatively more effective than other agents in metastatic brain tumor. In Korea, however, using it in the first-line treatment does not get insurance benefit, and it is very costly -- 6.5 million won a month,” said Park Keun-chil, a professor at the Oncology Division of Samsung Medical Center.
It is essential to see how the drug can prolong the life of the patient. After Tagrisso’s OS data is out in the first-line treatment, there will be an academic debate about it, Professor Park added.
As Tagrisso is not reimbursable in the first-line therapy, most of the local patients have no other choice but to receive the consecutive treatment – using other EGFT TKI in the first-line treatment and Tagrisso in the second-line one.
Experts noted that doctors need to compare the consecutive treatment’s OS with that of using Tagrisso for the first-line treatment because there is no drug to use if a Tagrisso-treated patient becomes resistant to the medication.
Using first-generation or second-generation EGFR TIKs cause T790M mutation in five or six patients out of 10, and these patients can continue the treatment with Tagrisso, they said.
Unless Tagrisso’s OS data shows a significantly strong benefit to override their arguments or a new drug arrives to treat Tagrisso-resistant patients, it will take some time to use Tagrisso as the first-line treatment, observers said.
According to the estimated survival analysis on the FLAURA results published in the American Society for Clinical Oncology in May, the estimated three- and five-year survival rates with Tagriss-treated patients were 57.3 percent and 31.1 percent, respectively. In comparison, the estimated three- and five-year survival rates with Tarceva/Iressa were 41.1 percent and 15.5 percent, respectively.
“Based on the best fitting parametric survival model to FLAURA OS data, the estimated five-year survival rate with Tagrisso was double that with Tarceva/Iressa,” the research team said.
Whether the upcoming OS data of Tagrisso will match the estimated survival results is drawing attention.