Long-term treatment with P1101 for patients with Polycythemia Vera or Essential Thrombocythemia

Extension Study of P1101 in Japanese Patients Who Have Completed Phase 2 Single Arm Study in Polycythemia Vera (PV) Patients (Study A19-201) or Phase 3 Study in Essential Thrombocythemia (ET) Patients (Study P1101 ET)

Phase 3 Interventional PharmaEssentia Japan K.K. · NCT04655092

This study is testing if a long-term treatment with P1101 can safely help people with Polycythemia Vera or Essential Thrombocythemia who have already tried other treatments.

Quick facts

PhasePhase 3
Study typeInterventional
Enrollment67 (estimated)
Ages20 Years and up
SexAll
SponsorPharmaEssentia Japan K.K. Industry-sponsored
Locations6 sites (Toon-shi, Ehime and 5 other locations)
Trial IDNCT04655092 on ClinicalTrials.gov

What this trial studies

This Phase 3 open-label, multicenter study aims to evaluate the long-term safety and efficacy of P1101 in patients with Polycythemia Vera (PV) or Essential Thrombocythemia (ET) who have previously participated in related studies. Participants who completed a 52-week treatment with P1101 or have been treated with anagrelide will receive P1101 at a specified dose, which may be adjusted based on their condition. The study will assess various safety and efficacy parameters, including vital signs, laboratory tests, and spleen size measurements, to determine the treatment's overall impact.

Who should consider this trial

Good fit: Ideal candidates are patients who have completed prior studies involving P1101 and have provided informed consent.

Not a fit: Patients who are deemed ineligible for continued treatment with P1101 by the investigator will not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a long-term management option for patients with PV or ET, improving their quality of life.

How similar studies have performed: Other studies involving P1101 have shown promise, indicating a potential for success in this long-term evaluation.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients who have completed the 52-week treatment duration in Study A19-201 and are considered by the investigator or sub investigator to be eligible for participation in this study
* Patients who have given written informed consent to participate in this study

Exclusion Criteria:

* Patients who are considered by the investigator or sub investigator to be ineligible for continued treatment with P1101

Where this trial is running

Toon-shi, Ehime and 5 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Polycythemia VeraMyeloproliferative Neoplasms
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.