Table 1.

Key eligibility criteria.

Inclusion criteria
1	Histologically or cytologically proven non-small cell lung cancer
2	Unresectable stage III/IV or recurrent
3	Received prior chemotherapy, including platinum doublet
4	Chronic fibrotic IP (all four items are required) (a) HRCT revealed (i) reticular shadow with basal, peripheral predominance suggestive of UIP pattern or (ii) peribronchovascular shadow suggestive of NSIP pattern(b) Without known etiology (e.g. infection, pneumoconiosis, drug, sarcoidosis, and collagen vascular disease)(c) %FVC > 70%(d) %DLCO > 35%
6	Age ⩾ 20 years
7	ECOG performance status 0–1
8	With measurable or unmeasurable lesions according to RECIST Version 1.1
9	Vital organ functions are preserved within 14 days prior to enrollment
10	Received sufficient explanations about the name and severity of the illness
11	Written informed consent
Exclusion criteria
1	History of acute exacerbation of pre-existing IP
2	Treatment history with immune checkpoint inhibitor
3	Systemic treatment with steroids at a daily dose of >10 mg of prednisolone or equivalent immunosuppressant
4	Active autoimmune disease or history of autoimmune disease requiring treatment
5	Symptomatic brain metastasis or spinal cord metastases
6	Active viral hepatitis
7	Local or systemic active infection requiring treatment
8	Synchronous or metachronous active double malignancies
9	Pregnant or breastfeeding
10	Disapprove of contraception during the protocol treatment period
11	Treatment history with thoracic radiotherapy
12	History of serious drug allergies
13	Other conditions not suitable for the study

DLCO, diffusing capacity of the lungs for carbon monoxide; ECOG, Eastern Cooperative Oncology Group; FVC, forced vital capacity; HRCT, high-resolution computed tomography; IP, interstitial pneumonia; NSIP, nonspecific interstitial pneumonia; RECIST, Response Evaluation Criteria in Solid Tumors; UIP, usual interstitial pneumonia.