Sumitomo Pharma Oncology has announced new preliminary findings from the ongoing Phase I/II trial of TP-3654 to treat myelofibrosis (MF) patients who were earlier treated with or ineligible for JAK inhibitor therapy.
TP-3654, an oral investigational PIM 1 kinase inhibitor, has demonstrated potential anti-tumour and anti-fibrotic activity via different pathways such as apoptosis induction in preclinical models.
Preliminary results of TP-3654 monotherapy in relapsed/refractory myelofibrosis (MF) patients demonstrated spleen volume reduction (SVR) and improvement in total symptom score (TSS).
TP-3654 could also lead to early cytokine changes that are expected to correlate with symptoms response.
Until 9 February 2023, 15 patients were included across five dose levels ranging from 480mg QD to 720mg BID.
As per the results, SVR was found in seven of ten evaluable patients treated for ≥ 12 weeks while TSS improvements were reported in nine of ten evaluable subjects.
Extensive reductions in cytokines were found following treatment with TP-3654. At week 12 evaluation, it was found that patients with higher cytokine reductions correlated with greater TSS improvement.
Furthermore, a reduction in bone marrow fibrosis from grade three to two was observed in one subject who also achieved spleen and symptoms responses and demonstrated decreases in MF-related cytokines.
In general, TP-3654 was found to be well tolerated without any dose-limiting toxicity observed so far. The most common adverse events included grade one and two diarrhoea, nausea along with vomiting.
Sumitomo Pharma Oncology chief medical officer and development global head Jatin Shah said: “These updated preliminary data of oral TP-3654 as a monotherapy in patients with MF presented at EHA 2023 are encouraging as we evaluate the pharmacodynamic markers changes in MF patients treated with TP-3654.
“We look forward to continuing to advance this study to evaluate the potential role of TP-3654 as a monotherapy, in addition to exploring combination opportunities with JAK inhibitors, for patients with myelofibrosis.”