519P - Final results and subgroup analysis of ORIENTAL: A phase IIIB study of durvalumab plus platinum-etoposide in first-line treatment of Chinese patients with extensive-stage small-cell lung cancer (ES-SCLC)

Background

The phase Ⅲ CASPIAN study established durvalumab (D) plus etoposide with cisplatin or carboplatin (EP) as first-line standard of care (1L SoC) of ES-SCLC. The multicenter, single-arm, phase Ⅲb ORIENTAL study evaluated 1L D+EP in a large, real-world-like patient (pt) cohort in China. Preliminary safety and efficacy results were consistent with CASPIAN. Here we report final results and subgroup analysis.

Methods

Treatment-naïve ES-SCLC pts ≥18 years old with ECOG PS 0–2 received D 1500 mg + EP intravenously every 3 weeks for 4–6 cycles, followed by D monotherapy every 4 weeks until progressive disease or intolerable toxicity. Primary endpoints were immune-mediated adverse events (imAEs) and grade ≥3 AEs. Secondary endpoints included OS, PFS, and tumor response.

Results

166 pts from 32 sites were enrolled by Aug 2021 and 165 received study treatment (median [m] age 65 years; 140 [84.8%] male). At baseline, 6 (3.6%) were ECOG PS 2, 155 (93.9%) were stage Ⅳ, 21 (12.7%) had brain metastases, and 44 (26.7%) had liver metastases. By data cut-off (31 Mar 2023), median cycle number of D was 7 (range 1–25). 92 (55.8%) started subsequent systemic anticancer therapy. 40 (24.2%) reported imAEs (most common [≥5%]: hyperthyroidism [6.1%] and hypothyroidism [6.1%]; grade 1/2 mostly). Grade ≥3 AEs occurred in 82 (49.7%) pts and led to treatment interruption in 24 (14.5%). mOS was 14.8 months (mo) (m follow-up [mFU] 20.5 mo). 118 (71.5%) pts received D maintenance, with mOS of 16.6 mo. 85 (51.5%) pts received >4 EP cycles, with mOS of 17.4 mo (Table). mPFS was 6.3 mo (mFU 8.6 mo). ORR was 76.4%, with 3 (1.8%) complete responses (RECIST 1.1). Table: 519P

Conclusions

Final results of ORIENTAL showed in the largest to date, real-world-like Chinese ES-SCLC cohort that D+EP was effective and well tolerated, further supporting D+EP as 1L SoC in China.

Clinical trial identification

NCT04449861.

Editorial acknowledgement

Medical writing support for the development of the abstract, under the input and direction of the authors, was provided by Xiaowei Ning and Bo Lyu from Costello Medical Singapore and funded by AstraZeneca China.

Legal entity responsible for the study

AstraZeneca China.

Funding

AstraZeneca China.

Disclosure

All authors have declared no conflicts of interest.