Evaluating progression-free survival of EGFR exon 20ins in patients with advanced non-small lung cancer receiving EGFR inhibitors: A real-world data study.

e20092 Background: EGFR mutations with exon 20 insertions (Exon20ins) have emerged as a distinct subset with significant clinical implications. Their prevalence is approximately 10%. Patients with Exon20ins have fewer available treatment options compared to common EGFR mutations. We therefore aimed to evaluate progression-free survival (PFS) in advanced and recurrent non-small cell lung cancer (NSCLC) patients harboring Exon20ins and treated with EGFR inhibitors. Methods: We searched the OpenCase database for stage III-IV advanced and recurrent NSCLC patients harboring (Exon20ins) mutation and limited to patients having received at least commercially available EGFR inhibitors (including off-label use). We extracted time to progression or longest duration of follow-up for all patients as well as key baseline characteristics. We calculated median PFS (IQR) across all patients. Subgroup analysis compared the sub-populations contingent on each having data from n>9 patients: line of therapy (1st, 2nd and 3rd+, Sex, Age (<65 years vs older), and smoking status (never vs former/current). Results: The number of patients harboring Exon20ins mutation was n=93. Filtering to patients who had received EGFR inhibitors yielded a sample size of n=36 patients. Fourteen patients had data on 2 or 3 lines of treatments, thus yielding n=53 PFS data points. The median age was 56.5 years (IQR: 39.7-68) with 63.8% females, and 69.4% never-smokers (11% missing values). PFS was available for 21, 12, and 13 patients on 1st, 2nd and 3rd+ line of therapy, respectively. EGFR inhibitors were Afatinib (13), Osimertinib (12), Furmonertinib (6), Anlotinib(6), Crizotinib (3), Poziotinib(2), Almonertinib(2), Apatinib (2), Other (8). The overall median PFS was 9.0 months (IQR: 5.0 to 10.3, min-max: 1 to 38). The median PFS was similar for 1st, 2nd and 3rd+ lines of treatment at 8.13, 8.0 and 9.5 months, respectively. The median PFS for females was 9 months (IQR: 3.8 to 12, n=36) versus 6.2 months (5 to 10, n=17). Lastly, the median PFS for patients younger than 65 years was 9 months (IQR: 5.3 to 12, n=39) versus 5.6 (IQR: 2,5 to 9.4, n=15) for older patients. Subgroup comparison for smoking status was not possible due to low number of former/current smokers. Conclusions: Our exploratory analysis suggested improved PFS among female, and younger patients. No differences were observed by treatment line or treatment.