A Phase 1/2 interventional study of gecacitinib Hydrochloride Tablets in Myeloid Neoplasms With Myelofibrosis, sponsored by Ruijin Hospital. Not yet recruiting at 1 site in China. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-20.
Sponsored by Ruijin Hospital · Phase 1/2, Interventional, and Prevention
This is a single-arm, single-center exploratory study evaluating the safety and efficacy of gecacitinib administered in the peri-transplant period in patients with myeloid neoplasms and myelofibrosis (MF) who are scheduled to undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT).Approximately 10 eligible patients will receive oral gecacitinib starting 13 weeks before transplantation. Treatment will continue through the peri-transplant period and for up to 24 weeks after hematopoietic reconstitution. The primary endpoint is the engraftment rate at day +28 post-transplant. Secondary endpoints include poor graft function rate, grade III-IV acute GVHD rate, overall survival, infection rate, and bone marrow fibrosis grade changes.
Background: Myelofibrosis (MF) and other myeloid neoplasms with myelofibrosis are associated with significant clinical symptoms that can adversely affect the outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT). JAK inhibitors are recommended as bridging therapy before transplantation in MF patients with high symptom burden, but the optimal peri-transplant management strategy remains an area of active investigation.
Gecacitinib is a next-generation JAK inhibitor that has demonstrated superior efficacy and a better hematologic safety profile than ruxolitinib in previous studies. In frontline patients with MF, treatment with gecacitinib resulted in a spleen volume response rate (SVR35) of 64.8%, significantly higher than ruxolitinib (27%), with a lower incidence of anemia than that observed with ruxolitinib (36.6% vs. 50.8%). Preclinical studies have also shown that gecacitinib can prolong survival and alleviate GVHD in a huPBMC-NCG mouse model.
Study Design: This is a single-arm, single-center, exploratory clinical study. Approximately 10 patients with myeloid neoplasms and bone marrow fibrosis of grade ≥2 who are scheduled to undergo their first allo-HSCT will be enrolled.
Intervention: gecacitinib will be administered orally starting 13 weeks before transplantation. The starting dose is determined by baseline platelet count: 100 mg BID for platelets ≥50×10\^9/L, or 50 mg BID for platelets \<50×10\^9/L. The dose will be reduced to 50 mg BID beginning 1 week before transplantation (day -7) and will be maintained at this dose during conditioning and transplantation, then increased to 100 mg BID after hematopoietic reconstitution (PLT ≥50×10\^9/L and ANC ≥0.5×10\^9/L), maintained for 12 weeks, then tapered to 50 mg BID for another 12 weeks before discontinuation.
Primary Outcome: Engraftment rate at day +28 post-transplant (defined as neutrophil count >0.5×10\^9/L for 3 consecutive days and platelet count >20×10\^9/L for 7 consecutive days without platelet transfusion support).
Follow-up: Patients will be followed for 2 years after transplantation or until death or loss to follow-up, whichever occurs first.
431 studies on the registry are indexed under Primary Myelofibrosis; 118 are open to participants now.
This study's planned enrollment of 10 is below the median of 44 across 355 interventional studies indexed under Primary Myelofibrosis.
Browse Primary Myelofibrosis studies →Ruijin Hospital is the lead sponsor of 667 studies on the registry; 376 are open to participants now.
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Exclusion Criteria:
Any significant clinical or laboratory abnormality that may affect safety evaluation, including:
gecacitinib is administered orally, starting 13 weeks before allo-HSCT. Starting dose is based on baseline platelet count: 100 mg twice daily (BID) if platelets ≥50×10\^9/L, or 50 mg BID if platelets \<50×10\^9/L.The dose will be reduced to 50 mg BID beginning on day -7 (1 week before transplantation) and maintained at this dose during conditioning and transplantation. After hematopoietic reconstitution (PLT ≥50×10\^9/L and ANC ≥0.5×10\^9/L), the dose is increased to 100 mg BID for 12 weeks, then tapered to 50 mg BID for another 12 weeks before discontinuation.
Drug: gecacitinib Hydrochloride Tablets
gecacitinib is administered orally, starting 13 weeks before allo-HSCT. Starting dose is based on baseline platelet count: 100 mg twice daily (BID) if platelets ≥50×10\^9/L, or 50 mg BID if platelets \<50×10\^9/L.The dose will be reduced to 50 mg BID beginning on day -7 (1 week before transplantation) and maintained at this dose during conditioning and transplantation. After hematopoietic reconstitution (PLT ≥50×10\^9/L and ANC ≥0.5×10\^9/L), the dose is increased to 100 mg BID for 12 weeks, then tapered to 50 mg BID for another 12 weeks before discontinuation. Dose adjustments are made based on adverse events and hematologic parameters, with a maximum dose of 100 mg BID and minimum of 50 mg once daily (QD).
Engraftment Rate at Day +28 Post-Transplant
Percentage of patients who achieve both neutrophil engraftment (ANC \>0.5×10\^9/L for 3 consecutive days) and platelet engraftment (PLT \>20×10\^9/L for 7 consecutive days without platelet transfusion) by day +28 after transplantation.
Time frame: Day +28 post-transplant
Incidence of Poor Graft Function (PGF) at Day +180
PGF is defined as persistent cytopenia(s), including ANC \<0.5×10\^9/L, PLT \<20×10\^9/L or platelet transfusion dependence, and/or Hb \<70 g/L or red blood cell transfusion dependence, lasting for at least 2 weeks after initial donor engraftment, with hypoplastic marrow, full donor chimerism, and exclusion of relapse, rejection, severe GVHD, active infection, drug-related myelosuppression, or other identifiable causes.
Time frame: Day +180 post-transplant
Incidence of Grade III-IV Acute Graft-Versus-Host Disease (aGVHD) at Day +180
Percentage of patients developing grade III-IV acute GVHD within 180 days after transplantation, graded according to standard criteria.
Time frame: Day +180 post-transplant
Overall Survival (OS) at 1 Year Post-Transplant
Overall survival is defined as the time from transplantation to death from any cause. The 1-year overall survival rate is the percentage of patients alive 1 year after transplantation.
Time frame: 1 year post-transplant
Incidence of Severe Infections Within 180 Days Post-Transplant
Percentage of patients experiencing grade ≥3 infections within 180 days after transplantation.
Time frame: Within 180 days post-transplant
Bone Marrow Fibrosis Grade Changes at Day +90 and Day +180
Proportion of patients with decreased, increased, or stable bone marrow fibrosis grade at day +90 and day +180 compared to baseline, assessed according to the 2016 WHO myelofibrosis grading criteria.
Time frame: Day +90 and Day +180 post-transplant
Safety and Tolerability - Adverse Events
Incidence and severity of treatment-emergent adverse events (TEAEs), graded according to NCI-CTCAE v5.0 criteria.
Time frame: From start of study drug until 28 days after last dose
Plan to share: Undecided — Since this study has not yet received ethical approval, the research protocol will be shared upon approval.
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Studies of the drug tested here: Jaktinib