A study on the stability of ritonavir form III processed in orbit and returned to Earth.

Despite notable progress in realizing the benefits of microgravity, the physical stability of therapeutics processed in space has not been sufficiently investigated. Environmental factors including vibration, acceleration, radiation, and temperature, if not addressed, could impact the feasibility of in-space drug processing. The presented work demonstrates the successful recovery of the metastable Form III of ritonavir generated in orbit. The samples processed in orbit, along with control samples of Form I, Form II, Form III, and amorphous ritonavir brought to space and back exhibited excellent physical and chemical stability when exposed to space environments. Stability was determined through comparison to reference samples processed and held on Earth. By providing a detailed experimental dataset centered on survivability, we address a key concern in pharmaceutical processing under microgravity with potential applications for both drug development on Earth and pharmaceutical needs for long-duration human exploration initiatives.