The efficacy of TAGRISSO was evaluated in the LAURA trial [NCT03521154], a double blind, randomized, placebo-controlled study in adult patients with locally advanced, unresectable stage III NSCLC with EGFR exon 19 deletions or exon 21 L858R mutations whose disease had not progressed during or following definitive platinum-based chemoradiation therapy. Eligible patients were randomized within 42 days prior to study randomization and had a WHO performance status of 0 or 1. Prior to study enrollment, patients received concurrent chemoradiation therapy (cCRT) or sequential chemoradiation therapy (sCRT) regimens, where at least 2 cycles every 3 weeks or 5 doses of weekly platinum-based chemotherapy and definitive radiation were to be completed ≤6 weeks prior to randomization. The study excluded patients who had progressive disease during or following definitive chemoradiation therapy and patients with Grade ≥2 pneumonitis after chemoradiation therapy or any ILD prior to chemoradiation therapy. Patient tumor tissue samples were required to have an EGFR exon 19 deletion or exon 21 L858R mutation, as identified by the cobas® EGFR Mutation Test v2 in a central laboratory or by an FDA-approved test at a CLIA certified or accredited laboratory. 

Patients were randomized (2:1) to receive either TAGRISSO 80 mg orally once daily or placebo until disease progression or unacceptable toxicity. Randomization was stratified by prior chemoradiation strategy (cCRT vs sCRT), tumor staging prior to chemoradiation (IIIA vs IIIB/IIIC), and by region (China versus rest of the world). Post progression, all patients were offered open label TAGRISSO if, in the opinion of the treating healthcare provider, there was an expected clinical benefit. Tumor assessments were performed every 8 weeks until week 48, and then every 12 weeks.

The major efficacy outcome measure was progression free survival (PFS) as assessed by blinded independent central review (BICR). Additional efficacy outcome measures included OS and CNS PFS.

A total of 216 patients were randomized (2:1) to TAGRISSO (n=143) or placebo (n=73). The study population characteristics were: median age 63 years (range 36-84 years); 13% ≥75 years old; 61% female; 82% Asian, 14% White, 1.4% American Indian or Alaska Native and 2.3% had reported race as other; 6% were Hispanic or Latino; and 70% were never smokers. Baseline WHO performance status was 0 (51%) or 1 (49%); 35% of patients had stage IIIA, 49% of patients had stage IIIB and 16% of patients had stage IIIC NSCLC; 4% had squamous and 96% had non-squamous histology; 54% had exon 19 deletions and 45% had exon 21 L858R mutations. Prior to randomization, 89% of patients received cCRT and 11% of patients received sCRT. All patients received platinum-based chemotherapy (55% carboplatin-based chemotherapy and 44% cisplatin-based chemotherapy). The median total dose of radiation was 60 Gy for patients in both arms.

LAURA demonstrated a statistically significant improvement in PFS for patients randomized to TAGRISSO as compared to placebo. Efficacy results from LAURA are summarized in Table 15, and the Kaplan-Meier curve for PFS is shown in Figure 3. While OS results were immature at the current analysis, with 36% of pre-specified deaths for the final analysis reported, no trend towards a detriment was observed.

Figure 3. Kaplan-Meier Curves of PFS as assessed by BICR in LAURA

All patients underwent magnetic resonance imaging (MRI) brain scans at baseline and at each follow-up during the study. In an exploratory analysis of site(s) of relapse, the proportion of patients with new CNS lesions at the time of disease progression was 17/143 patients (12%) on the TAGRISSO arm and 26/73 patients (36%) on the placebo arm.