Real-world experience of afatinib as first-line therapy for advanced EGFR mutation-positive non-small cell lung cancer in Korea

Sung Yong Lee; Chang-Min Choi; Yoon Soo Chang; Kye Young Lee; Seung Joon Kim; Sei Hoon Yang; Jeong Seon Ryu; Jeong Eun Lee; Shin Yup Lee; Ji Young Park; Young-Chul Kim; In-Jae Oh; Chi Young Jung; Sang Hoon Lee; Seong Hoon Yoon; Juwhan Choi; Tae Won Jang

doi:10.21037/tlcr-21-501

Real-world experience of afatinib as first-line therapy for advanced EGFR mutation-positive non-small cell lung cancer in Korea

Transl Lung Cancer Res. 2021 Dec;10(12):4353-4367. doi: 10.21037/tlcr-21-501.

Authors

Sung Yong Lee^#¹, Chang-Min Choi^#², Yoon Soo Chang³, Kye Young Lee⁴, Seung Joon Kim⁵, Sei Hoon Yang⁶, Jeong Seon Ryu⁷, Jeong Eun Lee⁸, Shin Yup Lee⁹, Ji Young Park¹⁰, Young-Chul Kim¹¹, In-Jae Oh¹¹, Chi Young Jung¹², Sang Hoon Lee¹³, Seong Hoon Yoon¹⁴, Juwhan Choi¹, Tae Won Jang¹⁵

Affiliations

¹ Korea University Guro Hospital, Seoul, South Korea.
² Ulsan University Asan Medical Center, Seoul, South Korea.
³ Yonsei University Gangnam Severance Hospital, Seoul, South Korea.
⁴ Konkuk University Medical Center, Seoul, South Korea.
⁵ Catholic University Seoul St. Mary's Hospital, Seoul, South Korea.
⁶ Wonkwang University Hospital, Iksan, South Korea.
⁷ Inha University Hospital, Incheon, South Korea.
⁸ Chungnam National University, Daejeon, South Korea.
⁹ Kyungpook National University Chilgok Hospital, Daegu, South Korea.
¹⁰ Hallym University Sacred Heart Hospital, Anyang, South Korea.
¹¹ Chonnam National University Medical School and Hwasun Hospital, Hwasun, South Korea.
¹² Daegu Catholic University Medical Center, Daegu, South Korea.
¹³ Yonsei University Severance Hospital, Seoul, South Korea.
¹⁴ Pusan National University Yangsan Hospital, Yangsan, South Korea.
¹⁵ Kosin University Gospel Hospital, Busan, South Korea.

^# Contributed equally.

Abstract

Background: We investigated the clinical characteristics and treatment outcomes of Korean patients receiving first-line afatinib for advanced epidermal growth factor receptor mutation-positive (EGFRm⁺) non-small cell lung cancer (NSCLC) in a real-world setting.

Methods: Electronic case reports were retrospectively reviewed from patients across 15 sites in South Korea. Outcome measures included baseline characteristics, overall response rate (ORR), time-to-treatment discontinuation (TTD), and overall survival (OS). Subgroups were: presence/absence of brain metastases at baseline, dose reductions, and baseline EGFR mutation category.

Results: Among 422 patients, 39.8% had brain metastases and 59.0%/25.1%/10.0%/5.0% had Del19/L858R/compound/uncommon EGFR mutations at baseline. ORR was 62.6% overall; responses were observed across all EGFR mutation categories, including against compound mutations. Median TTD was 17.8 months; median OS was not reached (NR). Median TTD and OS were longer in patients without versus with brain metastases (TTD: 22.9 vs. 14.8 months, P=0.001; OS: NR vs. 40.3 months, P=0.0009) and patients with versus without dose reductions (TTD: 22.2 vs. 14.2 months, P=0.0004; OS: NR vs. 40.3 months, P=0.0117). Median OS was 30.5/37.7 months in patients receiving chemotherapy/osimertinib as subsequent therapy. The most common treatment-related adverse events (TRAEs; any grade/grade ≥3) were diarrhea (31.3%/8.5%) and rash (23.0%/8.1%). Overall, 34 patients (8.1%) discontinued afatinib due to AEs.

Conclusions: Afatinib was well tolerated with no new safety signals, and efficacy was encouraging in Korean patients with EGFRm⁺ NSCLC, including those with baseline brain metastases and/or uncommon EGFR mutations. AE management with dose reductions facilitated a long TTD, prolonging the chemotherapy-free period for many patients.

Keywords: Afatinib; epidermal growth factor receptor (EGFR); first-line; non-small cell lung cancer (NSCLC); real-world.