A Single-arm, Multicenter Study to Assess the Efficacy, Safety, and Tolerability of P1101 in Adults With ET

Inclusion Criteria:

Male and female subjects ≥18 years old.
Subjects diagnosed with ET according to the World Health Organization (WHO) 2016 criteria.
Subjects that are cytoreductive treatment-naïve, or pre-exposed to HU and/or ANA, as specified below (according to Investigator's judgment and documented in the patient's medical record):
Interferon treatment-naïve.
Adequate hepatic function defined as bilirubin ≤1.5 × upper limit normal (ULN), prothrombin time (PT) (international normalized ratio, [INR]) ≤1.5 x ULN, albumin >3.5 g/dL, alanine aminotransferase (ALT) ≤2.0 x ULN, aspartate aminotransferase ≤2.0 x ULN at screening.
Creatinine clearance ≥40 mL/min (by Cockcroft-Gault equation).
Males and females of childbearing potential, as well as all women <2 years after the onset of menopause, must agree to use an acceptable form of birth control until 60 days following the last dose of the study drug, and females must agree to not breastfeed during the study.
Written informed consent obtained from the subject and ability for the subject to comply with the requirements of the study.
Platelet count >450 × 109/L at screening

Exclusion Criteria:

Any subject requiring a legally authorized representative
Any contraindications or hypersensitivity to IFN-α and/or its excipients
Co-morbidity with severe or serious condition that, in the Investigator's opinion, would jeopardize the safety of the subject or their compliance with the protocol, including significant cardiac disease (including New York Heart Association Class III-IV congestive heart failure and clinically significant arrhythmias) and pulmonary hypertension
History of major organ transplantation
Pregnant or lactating females
Subjects with any significant medical conditions that, in the opinion of the Investigator, would compromise the results of the study or may impair compliance with the requirements of the protocol, including but not limited to:
Use of any investigational drug <4 weeks prior to the first dose of study drug or not recovered from effects of prior administration of any investigational agent
Presence of more than one driver mutation (e.g., V617F JAK2 and CALR, CALR and MPL, V617F JAK2 and MPL)
Prior use of Ruxolitinib