7. Oral phenylbutyrate versus placebo outcomes (Mercuri 2007).
| Phenylbutyrate | Placebo | Difference (95% CI) | P value | |
| All ages | ||||
| Number of participants randomised | 54 | 53 | — | — |
| Number (%) of participants evaluable for analysis of HFMS | 45 (83%) | 45 (85%) | — | — |
| Mean (SD) HFMS | 12.1 (9.60) | 12.8 (9.86) | ‐0.7 (‐4.78 to 3.78) | 0.70 |
| Mean (SD) change in HFMSa | 0.60 (0.22) | 0.73 (0.29) | ‐0.13 (‐0.84 to 0.58) | 0.70 |
| Age > 5 years | ||||
| Mean (SD) change in muscle strength arm megascore (dynamometry)a | 1.56 (6.94) | ‐0.42 (8.61) | 1.98 (‐1.67 to 5.63) | 0.74 |
| Mean (SD) change muscle strength leg megascore (dynamometry)a | 4.26 (8.64) | 3.22 (6.26) | 1.04 (‐2.46 to 4.54) | 0.78 |
| Number (%) of participants evaluable for analysis of HFMS | 26 (48%) | 23 (43%) | — | — |
| Mean (SD) change in pulmonary function (FVC % of predicted value in litres)a | 0.03 (0.17) | ‐0.01 (0.27) | 0.04 (‐0.07 to 0.15) | 0.39 |
| Phenylbutyrate | Placebo | Risk ratio (95% CI) | P value | |
| All ages | ||||
| Number of participants with adverse events | 19 | 5 | 3.1 (1.25 to 7.84) | 0.01 |
| Number of withdrawals because of adverse events | 6 | 3 | 1.86 (0.49 to 7.11) | 0.9 |
| Number of severe adverse events | 1 | 2 | — | — |
| Number of participants with severe adverse events | 1 | 2 | 1.96 (0.18 to 21.0) | 1.0 |
CI: confidence interval; FVC: forced vital capacity; HFMS: Hammersmith Functional Motor Scale; SD: standard deviation;
aMean change from baseline.