Phase 2
N=29
Efficacy and Safety of P1101 in Polycythemia Vera Patients for Whom the Standard of Treatment is Difficult to Apply
Polycythemia Vera (PV)
Bottom Line
View on ClinicalTrials.gov: NCT04182100 ↗Enrolled (actual)
29
Serious AEs
0.0%
Results posted
Sep 2025
Primary outcome: Primary: Proportion of Subjects Who Achieved Durable Phlebotomy-free Complete Hematological Response (CHR) at Month 12 — 8 Participants
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 2
- Interventions
- P1101 (Drug); Low-dose aspirin (Drug); Phlebotomy (Procedure)
- Age
- Adult, Older Adult · 20+ yrs
- Sex
- All
- Sponsor
- PharmaEssentia Japan K.K.
- Primary completion
- Mar 2021
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Proportion of Subjects Who Achieved Durable Phlebotomy-free Complete Hematological Response (CHR) at Month 12 |
8 | — |
| SECONDARY Changes in Hct From Baseline |
46.85; -2.21; -2.95; -3.09; -5.45 | — |
| SECONDARY Changes in WBC Count From Baseline |
17.07; -8.50; -10.57; -11.29; -11.71 | — |
| SECONDARY Changes in Plt Count From Baseline |
747.3; -283.6; -423.0; -467.4; -493.6 | — |
| SECONDARY Changes in Spleen Size From Baseline |
2.587; 1.847; 2.604; 5.043 | — |
| SECONDARY Time to Requiring no Phlebotomy |
0.3; 0.1; 0.0; 0.0; 0.0 | — |
| SECONDARY Time Required to First Response |
11.90 | — |
| SECONDARY Duration of Response Maintenance |
3.38; 3.77 | — |
| SECONDARY Proportion of Subjects Without Thrombotic or Hemorrhagic Events |
— | — |
| SECONDARY Change of JAK2 Mutant Allelic Burden Over Time vs. Baseline |
72.1881; -4.9006; -7.4963; -12.4549; -19.1748 | — |
| SECONDARY PK of P1101 |
50.3 | — |
Summary
This is a Phase 2 single arm study to investigate efficacy and safety of P1101 for adult Japanese patients with PV.
Eligibility Criteria
Inclusion Criteria
- Male or female patients ≥20 years old
- Patients diagnosed with PV according to the WHO 2008 or WHO 2016 criteria
- PV patients for whom the current standard of treatment is difficult to apply. (Patients with a documented history of refractory to HU are excluded.)
- Younger patients (long-term treatment is anticipated)
- Patients who are categorized as low risk, but cytoreduction is recommended due to disease-related signs and symptoms (headache, dizziness, pruritus, night sweats, fatigue, erythromelalgia, vision disorders, scintillating scotoma, early satiety, abdominal distension).
- Patients with HU intolerance
- Total HU treatment duration shorter than 3 years (cumulatively) at screening
- For cytoreduction naïve patients only: PV in need of cytoreductive treatment, defined by fulfilling as one or more of the following criteria at baseline:
- at least one previous well documented major cardiovascular PV-related event in the medical history
- poor tolerance of phlebotomy (defined as a phlebotomy/ procedure-related adverse event causing significant adverse impact on the patient and limiting ability to apply phlebotomy with the intention to keep Hct 10 x 10^9/L for two measurements within the month prior treatment start)
- Adequate hepatic function defined as bilirubin ≤1.5 x upper limit normal (ULN), international normalized ratio (INR) ≤1.5 x ULN, albumin >3.5 g/dL, alanine aminotransferase (ALT) ≤2.0 x ULN, aspartate aminotransferase (AST) ≤2.0 x ULN at screening
- Hemoglobin (HGB) ≥10 g/dL at screening
- Neutrophil count ≥1.5 x 10^9/L at screening
- Serum creatinine ≤1.5 x ULN at screening
- Hospital Anxiety and Depression Scale (HADS) score 0-7 on both subscales (Patients with a borderline of HADS score [score 7 but 7% at baseline)
- History of any malignancy within for the past 5 years
- History of alcohol or drug abuse within the last year
- History or evidence of post polycythemia vera-myelofibrosis (PPV-MF), essential thrombocythemia, or any non-PV MPN
- Presence of circulating blasts in the peripheral blood within the last 3 months
- Use of any investigational drug(s), or investigational drug combinations <4 weeks prior to the first dose of study drug or not recovered from effects of prior administration of any investigational agent
Data sourced from ClinicalTrials.gov (NCT04182100). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.