A Phase 1/2 interventional study of N-Acetylcysteine in Myeloproliferative Neoplasm, MPN and Essential Thrombocythemia, sponsored by University of California, Irvine. Recruiting at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-03-10.
Sponsored by University of California, Irvine · Phase 1/2, Interventional, and Treatment
This is a phase I/II study evaluating the optimal dose of N-acetylcysteine (N-AC) in patients with myeloproliferative neoplasms (MPN).
This is a phase I/II open-label clinical trial determining the optimal biological dose (OBD) of N-acetylcysteine in subjects with myeloproliferative neoplasms. These are subjects who have a diagnosis of essential thrombocythemia (ET), polycythemia vera (PV), or myelofibrosis (MF).
667 studies on the registry are indexed under Myeloproliferative Disorders; 110 are open to participants now.
This study's planned enrollment of 27 is below the median of 47 across 462 interventional studies indexed under Myeloproliferative Disorders.
Browse Myeloproliferative Disorders studies →University of California, Irvine is the lead sponsor of 476 studies on the registry; 98 are open to participants now.
Of its 41 completed or terminated interventional studies of FDA-regulated products, 30 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Significant impairment of major organ function defined as
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients take N-Acetylcysteince 600 mg orally twice daily. This is the starting dose level for the study.
Drug: N-Acetylcysteine
Patients take N-Acetylcysteince 1200 mg orally twice daily. If DL1 is well tolerated, the next cohort will progress to this dose level.
Drug: N-Acetylcysteine
Patients take N-Acetylcysteince 1800 mg orally twice daily. If DL2 is well tolerated, the next cohort will progress to this dose level.
Drug: N-Acetylcysteine
Given PO
Also known as: N-AC
Optimal Biological Dose (OBD) of N-Acetylcysteine
Determination of the optimal biological dose (OBD) will be utilized to evaluate the safety and tolerability of N-AC as a treatment for patients with MPN. Optimal biological dose is defined as the therapeutic dose that possesses the highest efficacy probability while inducing acceptable toxicity
Time frame: From the start date of treatment until 7 days after completion of treatment or removal of treatment due to disease progression, toxicity, delay of treatment, or withdrawal of treatment, whichever came first, up to 8 weeks.
Proportion of subjects who achieve 30% reduction of MPN-SAF Total symptom score (MPN-TSS)
MPN-SAF Total symptom score (MPN-TSS) is a validated tool to objectively measure the burden of symptoms associated with MPN. Baseline TSS will be defined as the average of the daily TSS of 7 consecutive days immediately prior to beginning N-AC. The end of study MPN-TSS will be defined as the average of the daily TSS of 7 consecutive days during week 8.
Time frame: 7 days prior to beginning treatment until end of treatment, average of 9 weeks.
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Studies of the drug tested here: Acetylcysteine
Myeloproliferative Disorders →
University of California, Irvine →