| Macitentan 10 mg | Placebo | |
| Subjects n | 119 | 59 |
| Male | 84 (70.6) | 37 (62.7) |
| Age years | 66 (37–84) | 64 (49–81) |
| 65.1±7.85 | 64.5±6.32 | |
| IPF medical status | ||
| Duration of symptoms days | 786 (151–4348) | 771 (60–3180) |
| Duration since SLB-confirmed diagnosis days | 213 (3–1870) | 114 (2–1440) |
| Digital clubbing | 23 (19.3) | 8 (13.6) |
| Smoking | ||
| Never-smoker | 47 (39.5) | 22 (37.3) |
| Ex-smoker | 67 (56.3) | 37 (62.7) |
| Current smoker | 5 (4.2) | 0 (0.0) |
| Location | ||
| USA | 37 (31.1) | 18 (30.5) |
| Non-USA | 82 (68.9) | 41 (69.5) |
| FVC L | 2.83 (1.24–5.42) | 2.74 (1.36–6.61) |
| 2.88±0.83 | 2.79±0.78 | |
| FVC % pred | 76.1 (47.7–121.1) | 73.8 (54.0–126.4) |
| 76.5±15.6 | 74.8±14.6 | |
| Corrected DLCO mmol·kPa−1·min−1 | 4.16 (2.37–8.75) | 4.13 (2.25–8.70) |
| 4.55±1.49 | 4.35±1.32 | |
| Corrected DLCO % pred | 46.5 (26.3 to 90.7)# | 43.7 (30.7–76.1) |
| 47.8±13.4# | 45.6±11.2 | |
| Oral corticosteroid use | 28 (23.5) | 15 (25.4) |
| Daily dose mg prednisone equivalent | 10.4±3.42 | 12.1±5.17 |
| N-acetylcysteine use | 19 (16.0) | 13 (22.0) |
| Daily dose mg | 600±0.0 | 592±27.7 |
| Blood oxygenation mmHg | ||
| PaO2 | 77.9±11.5¶ | 80.2±15.0 |
| PA–aO2 | 21.2±10.8+ | 19.6±11.3§ |
Data are presented as n (%), median (range) or mean±sd, unless otherwise stated. IPF: idiopathic pulmonary fibrosis; SLB: surgical lung biopsy; FCV: forced vital capacity; DLCO: diffusing capacity of the lung for carbon monoxide; % pred: % predicted; PaO2: arterial oxygen tension; PA–aO2: alveolar–arterial oxygen tension difference. #: n=115; ¶: n=113; +: n=107; §: n=55.