A Study of Rusfertide in Adults With Polycythemia Vera (PV)

Inclusion criteria: 1. Male and female participants aged 18 (or the minimum country specific age of consent if greater than \[\>\]18) years or older. 2. Participant understands the study procedures, is willing and able to adhere to study requirements and agrees to participate in the study by giving written informed consent. 3. Meet revised 2016 World Health Organization (WHO) criteria for the diagnosis of PV. 4. Phlebotomy requiring defined as ALL of the following: 1. At least 3 phlebotomies due to inadequate hematocrit control in 28 weeks before randomization or at least 5 phlebotomies due to inadequate hematocrit control in 1 year before randomization, and 2. Last phlebotomy due to inadequate hematocrit control within 3 months before randomization, and 3. No phlebotomy within 6 days prior to randomization (do not include day of phlebotomy and day of randomization in the 6-day count). 5. Complete blood count (CBC) values immediately prior to randomization: 1. Hematocrit \<45%, 2. White blood cell count (WBC) 4000 cells per microlitre (/μL) to 20,000/μL (inclusive), and 3. Platelets 100,000/μL to 1,000,000/μL (inclusive). 6. Eastern Cooperative Oncology Group (ECOG) performance status 0, 1 or 2. 7. Women of childbearing potential (WOCBP) agree to use medically acceptable contraception (\<1% annual failure rate) during the study and for 30 days after the last dose of study drug. 8. A female participant must agree not to donate eggs (ova, oocytes) for the purposes of assisted reproduction during the study and for a period of 30 days after receiving the last dose of study medication. 9. Men with partners of childbearing potential agree to use medically acceptable contraception (\<1% annual failure rate) during the study and for 90 days after the last dose of study drug. In addition, men must use a condom during the study and for 90 days after the last dose of study drug regardless of the partner's childbearing potential. 10. A male participant must agree not to donate sperm for the purpose of reproduction during the study and for a minimum of 90 days after receiving the last dose. 11. Participants receiving cytoreductive therapy at randomization must be on a stable PV therapy regimen as follows: 1. Hydroxyurea - at least 2 months 2. Janus kinase (JAK) inhibitor - at least 2 months 3. Interferon - at least 6 months. 12. Participants treated with phlebotomy alone at randomization must have stopped: 1. Hydroxyurea at least 2 months before screening 2. JAK inhibitor at least 2 months before screening 3. Interferon at least 6 months before screening. Exclusion criteria: 1. Clinically meaningful laboratory abnormalities at Screening, including but not limited to the following: 1. Estimated glomerular filtration rate (eGFR) \<15 milliliters per minute per 1.73 square meters (mL/min/1.73 m\^2) 2. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥2.5×upper limit of normal (ULN) 3. Total bilirubin \>1.5×ULN 2. Participants who required phlebotomy at HCT levels lower than 45%. 3. Pregnant or lactating females. 4. Clinically significant thrombosis (e.g., deep vein thrombosis or splenic vein thrombosis) within 2 months prior to randomization. 5. Active or chronic bleeding within 2 months prior to randomization. 6. Met the criteria for post-PV myelofibrosis as defined by the International Working Group-Myeloproliferative Neoplasms Research and Treatment. 7. Any infection requiring systemic therapy within 1 month of dosing except controlled human immunodeficiency virus (HIV), hepatitis B, and hepatitis C. Prophylactic therapies were allowed. 8. Any serious or unstable medical condition (e.g., poorly controlled HIV infection) or uncontrolled psychiatric condition as judged by the Investigator that would impair the participant's ability to participate in the study. 9. Major surgical procedure within 2 months prior to randomization unless the participant had fully recovered from surgery or planned major elective surgery during the study. 10. History of invasive malignancies within the last 5 years, except 1. localized cured cancer (e.g., prostate cancer and cervical cancer) 2. localized cured in situ or Stage 1 squamous cell carcinoma (SCC) of the skin, basal cell carcinoma (BCC) of the skin, or in situ melanoma of the skin. 11. Participants with in situ or Stage 1 SCC of the skin, in situ or Stage 1 BCC of the skin, or in situ melanoma of the skin identified during the required dermatology examination at Screening unless the cancer was adequately treated (i.e., treatment that was expected to be curative, such as Mohs surgery) before randomization. Note: Suspicious lesions were to be biopsied and results made available before randomization. 12. Participants with active alcohol or drug addiction that would have interfered with their ability to comply with study requirements. 13. Participants who did not complete at least 4 days of MFSAF assessments within 1 week prior to randomization. 14. Receipt of an investigational agent within 2 months or 5 half-lives, whichever was longer, prior to randomization. 15. Received busulfan, pipobroman, or 32Phosphorus within 7 months prior to Screening. 16. Participants with hypersensitivity to rusfertide or to any of the excipients or placebo. 17. Participants with any lesion or mass detected by physical examination or imaging during screening that was suspicious for malignancy unless evaluated and assessed to be not malignant.