AstraZeneca Imfinzi/tremelimumab combo shows survival benefit in lung cancer in 4-year data
Lisa Maree Williams

AstraZeneca (NASDAQ:AZN) said ~4 years of follow-up data from a phase 3 trial suggested that a limited five cycles of tremelimumab added to Imfinzi (durvalumab) plus four cycles of chemotherapy improved overall survival (OS) by 25% compared to chemotherapy alone as initial treatment of patients with stage IV (metastatic) non-small cell lung cancer (NSCLC).
Additional analyses from the phase 3 trial, dubbed POSEIDON, continued to show a trend for OS improvement with this combination in patients with STK11, KEAP1 and KRAS-mutated NSCLC, and in patients whose tumors were PD-L1-negative (less than 1% tumor cell expression), the company said in a Sept. 11 press release.
Updated median OS was 14 months for the combination therapy, compared to 11.7 months for chemotherapy alone. An estimated 25% of patients treated with the combination were alive at three years, compared to 13.6% for those treated with chemotherapy alone, AstraZeneca added.
The company noted that a 32% improvement in OS compared to chemotherapy alone was reported for patients with non-squamous histology, with an updated median OS of 17.2 months for the combination versus 13.1 months for chemotherapy.
Serious treatment-related adverse events (AEs) of any grade occurred in 27.6% of patients in the combination group, versus 17.7% in the standalone chemotherapy group.
AstraZeneca said treatment-related AEs leading to death occurred in 3.3% of patients in the combination arm versus 2.4% in the chemotherapy group.
AZN +1.31% to $61.65 premarket Sept. 12