Karyopharm Therapeutics has commenced dosing of the first subject in the Phase II expansion of the Phase I/II clinical trial of oral medicine eltanexor (KPT-8602) in patients with various kinds of haematologic and solid tumour cancers.
Eltanexor is a novel experimental Selective Inhibitor of Nuclear Export (SINE) compound that works by attaching with and hindering XPO1, a nuclear export protein.
The ongoing open-label Phase I/II trial is designed to assess eltanexor as monotherapy or along with various approved and experimental agents.
The Phase II expansion will analyse eltanexor as a single agent in hypomethylating agents (HMA) refractory, intermediate or high-risk myelodysplastic syndrome (MDS) patients.
Overall response rate (ORR) will be the primary goal of this segment while secondary goals will include progression-free and overall survival (OS) assessments.
Phase II commenced on obtaining positive data from the Phase I segment of the trial where eltanexor monotherapy demonstrated activity in increased-risk, relapsed MDS patients who are refractory to HMAs.
Furthermore, the medicine showed a 53% ORR and a median OS of 9.9 months, as against controls.
The monotherapy was found to be well tolerated at the recommended Phase II 10mg dose, with reduced occurrence and severity of gastrointestinal events.
Cytopenias exacerbation was reported in 20%-40% of subjects.
Based on these data, the trial was extended to enrol another 83 subjects.
Karyopharm Therapeutics co-founder and chief scientific officer Sharon Shacham said: “MDS is a group of diseases characterised by ineffective production of the components of the blood due to poor bone marrow function, leading to a high risk of transformation into acute leukaemia.
“Based on the promising signal observed in the prior Phase I study, we are pleased to initiate dosing in the Phase II expansion and look forward to updating you on the progress of this important study in the future.”