This was a phase 1 clinical trial in patients with metastatic tyrosine kinase inhibitor (TKI)-resistant gastrointestinal stromal tumours (GIST).
Treatment was a combination of onalespib (a heat-shock protein 90 inhibitor) and imatinib (a TKI).
Treatment was well tolerated and toxicities consistent with known safety profiles.
Disease control at 4 months was seen in five patients (19%); median progression-free survival was 112 d.
One patient with PDGFRA-mutant GIST had a partial response for more than 376 d.