Durvalumab With or Without Tremelimumab in Combination With Chemotherapy as First-Line Therapy for Metastatic Non-Small-Cell Lung Cancer: The Phase III POSEIDON Study

• Published in: Journal of clinical oncology Vol. 41; no. 6; pp. 1213 - 1227
• Main Authors: Johnson, Melissa L, Cho, Byoung Chul, Luft, Alexander, Alatorre-Alexander, Jorge, Geater, Sarayut Lucien, Laktionov, Konstantin, Kim, Sang-We, Ursol, Grygorii, Hussein, Maen, Lim, Farah Louise, Yang, Cheng-Ta, Araujo, Luiz Henrique, Saito, Haruhiro, Reinmuth, Niels, Shi, Xiaojin, Poole, Lynne, Peters, Solange, Garon, Edward B, Mok, Tony
• Format: Journal Article
• Language: English
• Published: United States Wolters Kluwer Health 20-02-2023
• Subjects: Antibodies, Monoclonal - therapeutic use; Antineoplastic Combined Chemotherapy Protocols - adverse effects; Carcinoma, Non-Small-Cell Lung - pathology; Humans; Lung Neoplasms - pathology; ORIGINAL REPORTS
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/JCO.22.00975

The open-label, phase III POSEIDON study evaluated tremelimumab plus durvalumab and chemotherapy (T + D + CT) and durvalumab plus chemotherapy (D + CT) versus chemotherapy alone (CT) in first-line metastatic non-small-cell lung cancer (mNSCLC).
Patients (n = 1,013) with
/
wild-type mNSCLC were randomly assigned (1:1:1) to tremelimumab 75 mg plus durvalumab 1,500 mg and platinum-based chemotherapy for up to four 21-day cycles, followed by durvalumab once every 4 weeks until progression and one additional tremelimumab dose; durvalumab plus chemotherapy for up to four 21-day cycles, followed by durvalumab once every 4 weeks until progression; or chemotherapy for up to six 21-day cycles (with or without maintenance pemetrexed; all arms). Primary end points were progression-free survival (PFS) and overall survival (OS) for D + CT versus CT. Key alpha-controlled secondary end points were PFS and OS for T + D + CT versus CT.
PFS was significantly improved with D + CT versus CT (hazard ratio [HR], 0.74; 95% CI, 0.62 to 0.89;
= .0009; median, 5.5
4.8 months); a trend for improved OS did not reach statistical significance (HR, 0.86; 95% CI, 0.72 to 1.02;
= .0758; median, 13.3
11.7 months; 24-month OS, 29.6%
22.1%). PFS (HR, 0.72; 95% CI, 0.60 to 0.86;
= .0003; median, 6.2
4.8 months) and OS (HR, 0.77; 95% CI, 0.65 to 0.92;
= .0030; median, 14.0
11.7 months; 24-month OS, 32.9%
22.1%) were significantly improved with T + D + CT versus CT. Treatment-related adverse events were maximum grade 3/4 in 51.8%, 44.6%, and 44.4% of patients receiving T + D + CT, D + CT, and CT, respectively; 15.5%, 14.1%, and 9.9%, respectively, discontinued treatment because of treatment-related adverse events.
D + CT significantly improved PFS versus CT. A limited course of tremelimumab added to durvalumab and chemotherapy significantly improved OS and PFS versus CT, without meaningful additional tolerability burden, representing a potential new option in first-line mNSCLC.