ClinicalTrials.gg
RecruitingNCT05123365Updated Mar 10, 2026

An Optimal Dose Finding Study of N-Acetylcysteine in Patients With Myeloproliferative Neoplasms

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

From the registry’s dates

  • Started Jan 2022; still recruiting 4 years 10 months later.
Phase
Phase 1/2
Study type
Interventional
Enrollment
27
Allocation
Non-randomized
Ages
18 Years and older
Sex
All
01

Study summary

This is a phase I/II study evaluating the optimal dose of N-acetylcysteine (N-AC) in patients with myeloproliferative neoplasms (MPN).

Read the detailed description

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).

02

Conditions studied

  • Myeloproliferative Neoplasm
  • MPN
  • Essential Thrombocythemia
  • Polycythemia Vera
  • Myelofibrosis

Keywords

  • MPN
  • Myeloproliferative Neoplasm
  • Essential Thrombocytemia
  • Polycythemia Vera
  • Myelofibrosis
03

In context

Myeloproliferative Disorders

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 →

Lead sponsor

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.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

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.

Inclusion criteria

  • ≥18 years of age
  • Have a diagnosis of essential thrombocythemia (ET), polycythemia vera (PV), or myelofibrosis (MF) according to the 2016 WHO criteria
  • Has not taken interferon-alpha or a JAK inhibitor (such as ruxolitinib or fedratinib) for treatment of MPN in the past 28 days before enrollment.
  • May continue on current MPN treatment, including aspirin, hydroxyurea, or anagrelide. Therapeutic phlebotomies should continue per the patient's usual regimen.
  • Has not taken N-Acetylcysteine (N-AC) or preparations containing N-AC in the past 28 days before enrollment.
  • Baseline MPN-TSS score of ≥ 10 at the time of enrollment.
  • Peripheral blast count \<10% during Screening.
  • Free of other active or other than localized skin cancer.
  • Amenable to blood draws and symptom assessments.
  • Agree to the use of . Female subjects of and their male partners, or male subjects who have female partners of childbearing potential, should both use an effective contraception method during the study and continue to use contraception for 60 days after the last dose of study drug.

Exclusion criteria

Exclusion Criteria:

  • (ECOG) questionnaire score of ≥3
  • Currently pregnant or planning on being pregnant within the study period.
  • Currently breastfeeding.
  • Known uncontrolled active viral or bacterial infection.
  • Significant impairment of major organ function defined as

    1. Serum less than 50 ml/min (calculated with Cockroft-Gault formula).
    2. more than 1.5 mg/dl except for Gilbert's disease. or AST more than 2X upper normal limit or has radiologic evidence of liver cirrhosis.
    3. \< 100 × 10\^9/L
    4. \< 10 g/dL
    5. ANC \< 0.75 × 10\^9/L
  • Known history of allergic reaction to N-AC.
Terms in these criteria, in plain language(10)

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.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

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.

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.

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.

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.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

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.

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.

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.

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.

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.

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).

05

Study design

Phase
Phase 1 / Phase 2
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
27 participants (estimated)

Study arms

  • Experimental
    Dose Level 1 (DL1)

    Patients take N-Acetylcysteince 600 mg orally twice daily. This is the starting dose level for the study.

    Drug: N-Acetylcysteine

  • Experimental
    Dose Level 2 (DL2)

    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

  • Experimental
    Dose Level 3 (DL3)

    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

Interventions

06

What researchers measure

Primary outcomes

  1. 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.

  2. 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.

07

Study locations

1 of 2 sites recruiting
  • University of California, Irvine
    Irvine, California 92617, United States
    Recruiting
    • Angela G Fleischman, MD PhD · Contactagf@uci.edu · (949) 999-2400
  • Chao Family Comprehensive Cancer Center, University of California, Irvine
    Orange, California 92868, United States
    Active, not recruiting

    Not enrolling at this site.

08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 10, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT05123365
Responsible party
Angela G. Fleischman (Associate Professor, University of California, Irvine) — Principal investigator
First posted
Nov 17, 2021
Start date
Jan 3, 2022
Primary completion
Nov 15, 2026 (estimated)
Completion
Nov 15, 2026 (estimated)
Last update
Mar 10, 2026

Study contacts

Angela Fleischman, MD, PhD
Contact
agf@hs.uci.edu
(714) 456-8000
University of California Irvine Medical Center
Contact
Angela Fleischman, MD, PhD
principal investigator · Chao Family Comprehensive Cancer Center

Oversight

FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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