Characteristics, Outcomes Among Patients With Advanced NSCLC and HER2 Mutations

A greater understanding of patients with human epidermal growth factor receptor 2 (HER2)-mutated non-small cell lung cancer (NSCLC) and the associated tumor biology is critical for developing effective therapies, but information on real-world outcomes has been limited. Results from a study that analyzed real-world characteristics and outcomes among patients with HER2-mutated NSCLC from the US-based, deidentified Flatiron Health and Foundation Medicine’s Clinico-Genomic Database were presented at the 2023 North America Conference on Lung Cancer.

The researchers found that among 11,794 adults with advanced NSCLC between 2015 and 2021, 550 had a HER2 mutation (prevalence, 4.7%). The median age at diagnosis was 69.2 years, and 66.9% had a HER2 mutation type in the tyrosine kinase domain (TKD); 70.7% had a non-TKD mutation. In addition, half of the patients were female, 25.4% were never-smokers, and 65.3% were White.

Results showed that patients with a TKD mutation (n=200; 1.7%) tended to be female (60% vs 44% of non-TKD [n=346; 2.9%]) and never-smokers (44% vs 15% of non-TKD). The researchers also found they had lower tumor mutational burden (TMB; 75% of TKD vs 39% of non-TKD, with TMB <10 mutations/Mb). Results showed the most common HER2 variant was A775_G776insYVMA (n=95).

Overall, 405 patients received first-line treatment; 226 (55.8%) received platinum-based chemotherapy alone (platinum) or with immunotherapy (platinum-IO). Further, among 221 patients treated with second-line therapies, 50 (22.6%) received platinum or platinum-IO. Results showed median real-world overall survival (OS) and real-world progression-free survival (PFS) with any second-line regimen in months were 10.1 (range, 7.8-12.9 months) and 3.2 (range, 2.6-3.9 months), respectively.

The researchers concluded that their study further “elucidates the epidemiology and outcomes of patients with HER2-mutated NSCLC.” They “anticipate outcomes to change as the therapeutic landscape for patients with HER2-mutated lung cancer continues to evolve.”

Source: Baik C, Le X, Lovly CM, et al. Real-world characteristics and outcomes among patients with advanced non-small cell lung cancer (NSCLC) and HER2 mutations. Abstract of a poster presented at the 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, Illinois.