The goal of this clinical trial is to assess the safety, tolerability, pharmacokinetics, pharmacodynamics and immunogenicity of 9MW3011 in Chinese patients with Polycythemia Vera（PV）.
Male and female patients aged 18 years or older at the time of screening.
A confirmed diagnosis of PV according to the revised 2016 World Health Organization criteria and are resistant to or intolerant of hydroxyurea or Interferon alpha.
Have a treatment history for PV with resistance or intolerance to hydroxyurea or Interferon alpha.
Subjects receiving hydroxyurea, Interferon alpha, or ruxolitinib must complete a washout period before administration of the investigational drug.
The spleen is palpable at least 5 centimeters below the left costal margin upon palpation at baseline.
Heart failure, unstable angina pectoris, myocardial infarction, and other thrombotic diseases within the 6 months prior to screening.
Abnormal QTc interval of electrocardiogram within the 6 months prior to screening.
Uncontrolled hypertension prior to screening.