2.3. Spray Drying of COMPOUND A with HPMCAS-L

A spray dried formulation with HPMCAS-L was generated as benchmark formulation. Compound A was dissolved in acetone at 20 mg/mL together with 40 mg/mL HPMCAS-L. The solution was spray dried in a lab scale spray dryer (ProCepT R&D Spray Dryer, Zele, Belgium) with 0.60 mm bifluid nozzle under the following conditions: Inlet air temperature 81 °C, and outlet air temperature 53 °C. The gas flow is 0.4 m³/min, and the atomization air rate 5.0 L/min. Solution flow rate is 5 mL/min, and the cyclone pressure is 30 mBar. The spray dried dispersion was secondary dried at 40 °C overnight under vacuum before further use. The material was confirmed to be single phase amorphous solid dispersion by powder x-ray diffraction (Figure S1a) and modulated differential scanning calorimetry (Figure S1b).