有晶型I的，但是还没时间具体检索，
EMEA明确了其最稳定晶型：
Several polymorphic forms have been described including different solvates. All macitentan batches manufactured so far for clinical studies and commercial purposes correspond to the same stable polymorphic form which is a true polymorph with a melting point of 135°C. It is the thermodynamically most stable form at room temperature. Long-term stability studies on several clinical and registration batches showed no polymorphic change of after up to 36 months of storage at 30 °C / 65% RH. Results of the dynamic vapour sorption of macitentan show that it is not hygroscopic.
