A phase II study of atezolizumab for pretreated non-small cell lung cancer with idiopathic interstitial pneumonias

Ikeda, Satoshi; Kato, Terufumi; Kenmotsu, Hirotsugu; Ogura, Takashi; Iwasawa, Shunichiro; Sato, Yuki; Harada, Toshiyuki; Kubota, Kaoru; Tokito, Takaaki; Okamoto, Isamu; Furuya, Naoki; Yokoyama, Toshihide; Hosokawa, Shinobu; Iwasawa, Tae; Yamanaka, Takeharu; Okamoto, Hiroaki

Abstract Introduction Interstitial pneumonia (IP) is one of the most common and poor prognostic comorbidities in patients with non-small cell lung cancer (NSCLC) and is also a known risk factor for pneumonitis. Atezolizumab monotherapy is an established treatment for recurrent NSCLC, and were reported to have a lower risk of pneumonitis than PD-1 inhibitors. This study aims to assess the safety and efficacy of atezolizumab monotherapy for pretreated advanced or recurrent NSCLC patients with idiopathic IP. Methods Advanced/recurrent NSCLC patients with comorbid idiopathic, chronic fibrotic IP with %forced vital capacity (FVC) of > 70% and no history of immune checkpoint inhibitors (ICIs) were enrolled. The patients received atezolizumab (1200 mg) every three weeks until the discontinuation criteria are met. The primary end point of this study is the one-year survival rate. A sample size of 38 patients was set. Results This study was terminated early due to high incidence of pneumonitis. Seventeen patients were enrolled, with a median age of 70 years. The median %FVC and %diffusing capacity for carbon monoxide at baseline were 85.4% and 54.4%, respectively. The incidence of pneumonitis was 29.4% (5/17) for all grade, 23.5% (4/17) for grade ≥ 3, and 5.9% (1/17) for grade 5. 57.1% (4/7) of patients with honeycomb lung developed grade ≥3 pneumonitis, whereas only one patient (10%) of grade 1 pneumonitis was found in patients without honeycomb lung (n=10). Conclusions NSCLC patients with comorbid IP as defined by the selection criteria for this study may have an increased risk of ICI-induced pneumonitis.