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Oct 28 (Reuters) - AstraZeneca Plc said on Monday a combination of its cancer drug, Imfinzi, along with chemotherapy helped curb progression of lung cancer in a late-stage study, sending its shares up as much as 2%.
The combination, when added to the drugmaker's tremelimumab therapy, also met the secondary goal of improving progression-free survival, the British drugmaker said.
The triple combination delivered a broadly similar safety profile to the Imfinzi and chemotherapy combination and did not result in increased discontinuation of therapy, AstraZeneca said.
Shares of Merck & Co Inc, whose drug Keytruda is a dominant treatment for advanced lung cancer, dropped as much as 2% after the data.
Cantor Fitzgerald analyst Louise Chen said she would wait for additional data on extending survival, expected in 2020, before extrapolating much from the trial.
"If the data end up being competitive to Merck's Keytruda trials, this positive-sounding safety data could support true commercial viability for the triple combo," Chen said.
The combinations were being tested in previously untreated patients with stage four, non-small cell lung cancer.
Imfinzi and tremelimumab belong to the immunotherapy class of treatments, which strengthen the body's defenses to fight cancer and tumors.
AstraZeneca's Imfinzi, when combined with chemotherapy, significantly improved the survival of patients in the trial without their disease progressing, when compared with chemotherapy as a standalone treatment, the company said.
AstraZeneca's U.S.-listed shares were up nearly 1% at $48.07 in afternoon trading. (Reporting by Manas Mishra in Bengaluru; Editing by Shailesh Kuber and Maju Samuel)