TABLE 1.
Demographics and baseline clinical characteristics
| Placebo (n=41) | MK-5475 32 µg (n=42) | MK-5475 100 µg (n=44) | MK-5475 380 µg (n=41) | Total (N=168) | |
|---|---|---|---|---|---|
| Age, years | |||||
| Median (range) | 51.0 (19–73) | 50.5 (18–75) | 51.0 (19–74) | 48.0 (18–75) | 51.0 (18–75) |
| Mean±sd | 52.1±12.7 | 48.1±16.9 | 51.7±14.2 | 47.6±15.9 | 49.9±15.0 |
| Sex | |||||
| Female | 28 (68.3) | 34 (81.0) | 32 (72.7) | 30 (73.2) | 124 (73.8) |
| Male | 13 (31.7) | 8 (19.0) | 12 (27.3) | 11 (26.8) | 44 (26.2) |
| Race | |||||
| White | 32 (78.0) | 34 (81.0) | 41 (93.2) | 36 (87.8) | 143 (85.1) |
| Black or African American | 2 (4.9) | 3 (7.1) | 1 (2.3) | 1 (2.4) | 7 (4.2) |
| Asian | 3 (7.3) | 1 (2.4) | 0 | 0 | 4 (2.4) |
| Native American or Alaska native | 3 (7.3) | 0 | 0 | 0 | 3 (1.8) |
| Multiple | 1 (2.4) | 4 (9.5) | 2 (4.5) | 4 (9.8) | 11 (6.5) |
| Body mass index, kg·m−2 | 26.5# (18.7–40.6) | 29.3 (17.7–39.6) | 25.4 (18.5–38.0) | 25.9 (19.3–39.2) | 26.2 (17.7–40.6) |
| Time since PAH diagnosis, years | 5.0 (0.0–34.0) | 5.5 (0.0–27.0) | 4.6 (0.3–26.0) | 4.0 (0.3–36.0) | 4.8 (0.0–36.0) |
| Classification of PAH | |||||
| Idiopathic | 32 (78.0) | 25 (59.5) | 27 (61.4) | 23 (56.1) | 107 (63.7) |
| Heritable | 4 (9.8) | 5 (11.9) | 5 (11.4) | 4 (9.8) | 18 (10.7) |
| Drug- or toxin-induced | 0 | 3 (7.1) | 0 | 1 (2.4) | 4 (2.4) |
| CTD-PAH | 3 (7.3) | 7 (16.7) | 11 (25.0) | 10 (24.4) | 31 (18.5) |
| CHD-PAH | 2 (4.9) | 2 (4.8) | 1 (2.3) | 3 (7.3) | 8 (4.8) |
| WHO functional class | |||||
| II | 27 (65.9) | 27 (64.3) | 28 (63.6) | 26 (63.4) | 108 (64.3) |
| III/IV¶ | 14 (34.1) | 15 (35.7) | 16 (36.4) | 15 (36.6) | 60 (35.7) |
| Background PAH therapy | |||||
| Monotherapy | 8 (19.5) | 8 (19.0) | 6 (13.6) | 3 (7.3) | 25 (14.9) |
| Double therapy | 14 (34.1) | 15 (35.7) | 23 (52.3) | 24 (58.5) | 76 (45.2) |
| Triple therapy | 19 (46.3) | 19 (45.2) | 15 (34.1) | 14 (34.1) | 67 (39.9) |
| PDE5i | 38 (92.7) | 39 (92.9) | 42 (95.5) | 38 (92.7) | 157 (93.5) |
| ERA | 32 (78.0) | 33 (78.6) | 38 (86.4) | 38 (92.7) | 141 (83.9) |
| Oral prostacyclin | 11 (26.8) | 12 (28.6) | 9 (20.5) | 7 (17.1) | 39 (23.2) |
| i.v./s.c. prostacyclin | 12 (29.3) | 11 (26.2) | 8 (18.2) | 10 (24.4) | 41 (24.4) |
| 6MWD, m | 406.9±71.0 | 378.7±77.1 | 403.1±65.1 | 389.5±71.2 | 394.6±71.4 |
| NT-proBNP, pg·mL−1 | 604.9±902.7 | 621.0±1419.9 | 859.3±1796.9 | 632.0±1134.6 | 682.1±1354.1 |
| PVR, WU | 7.8±3.6 | 8.6±3.7 | 9.0±4.7 | 9.1±5.8 | 8.7±4.5 |
| Mean RAP, mmHg | 8.0±3.3 | 7.7±4.0 | 8.1±4.1 | 8.9±5.8 | 8.1±4.4 |
| Mean PAP, mmHg | 46.3±11.6 | 48.9±11.9 | 49.9±14.6 | 49.8±17.6 | 48.8±14.1 |
| PAWP, mmHg | 10.6±3.3 | 9.9±3.9 | 10.8±3.3 | 10.6±3.0 | 10.5±3.4 |
| Cardiac output, L·min−1 | 5.0±1.3 | 4.8±1.4 | 4.7±1.2 | 5.0±1.7 | 4.9±1.4 |
| Cardiac index, L·min−1·m−2 | 2.8±0.8 | 2.6±0.9 | 2.6±0.7 | 2.8±0.9 | 2.7±0.8 |
| Stroke volume index, mL·m−2 | 37.1±10.6 | 36.0±11.8 | 36.6±8.8 | 38.8±12.3 | 37.1±10.9 |
| PAC, mL·mmHg−1 | 1.5±0.5 | 1.5±0.6 | 1.4±0.4 | 1.8±1.1 | 1.6±0.7 |
| SVR, WU | 16.8±4.8 | 17.7±5.0 | 17.7±5.6 | 16.8±6.7 | 17.3±5.6 |
| SvO2, % | 69.3±7.8 | 70.2±6.3+ | 68.8±7.2+ | 68.4±7.3 | 69.2±7.1 |
| SaO2, % | 94.4±4.4§ | 94.4±3.1§ | 94.3±3.5§ | 93.8±5.4 | 94.2±4.2 |
| SBP, mmHg | 112.5±13.5 | 113.1±15.6 | 114.6±11.0 | 108.2±12.7 | 112.1±13.4 |
Data are presented as n (%), median (range) or mean±sd, unless otherwise indicated. PAH: pulmonary arterial hypertension; CHD-PAH: congenital heart disease-associated PAH; CTD-PAH: connective tissue disease-associated PAH; WHO: World Health Organization; PDE5i: phosphodiesterase type 5 inhibitors; ERA: endothelin receptor antagonists; 6MWD: 6-min walk distance; NT-proBNP: N-terminal prohormone of brain natriuretic peptide; PVR: pulmonary vascular resistance; WU: Wood units; RAP: right atrial pressure; PAP: pulmonary arterial pressure; PAWP: pulmonary artery wedge pressure; PAC: pulmonary arterial compliance; SVR: systemic vascular resistance; SvO2: mixed venous oxygen saturation; SaO2: arterial oxygen saturation; SBP: systolic blood pressure. #: one participant in the placebo group had missing data for body mass index; ¶: none of the participants had WHO functional class IV at the time of randomisation; +: one participant in the MK-5475 32 µg and two participants in the MK-5475 100 µg groups had missing data for SvO2; §: three participants in the placebo, two participants in the MK-5475 32 µg, and two participants in the MK-5475 100 µg groups had missing data for SaO2.