ClinicalTrials.gg
CompletedNCT03645863Updated Apr 6, 2026Results posted

Effects of Iron Supplements on the Pharmacokinetics of MT-6548

A Phase 3 interventional study of MT-6548 and Iron supplement A in Healthy, sponsored by Tanabe Pharma Corporation. Completed at 1 site in Japan. Open to male participants aged 20 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-04-06.

Sponsored by Tanabe Pharma Corporation · Phase 3, Interventional, and Other

Phase
Phase 3
Study type
Interventional
Enrollment
61
Allocation
Randomized
Ages
20 Years to 45 Years
Sex
Male
01

Study summary

The objectives of this study are to investigate the pharmacokinetics and safety of MT-6548 co-administered with iron supplements in healthy male volunteers.

02

Conditions studied

  • Healthy
03

In context

Lead sponsor

Tanabe Pharma Corporation is the lead sponsor of 92 studies on the registry; 1 is open to participants now.

Of its 8 completed or terminated interventional studies of FDA-regulated products, 6 (75%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
20 Years to 45 Years
Sexes eligible
Male
Accepts healthy volunteers
Yes

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

  • Parents and each grandparent of subjects are Japanese
  • Subjects judged as appropriate for this study by investigators based on the results of the tests at Screening, Day -1 and Day 1

Exclusion criteria

Exclusion Criteria:

  • Subjects with signs of heart diseases on the result of screening test
  • Subjects with current conditions or histories of drug addiction or alcohol addiction
  • Subjects judged by investigators that they cannot comply with the prohibition during the confinement period
  • Subjects who have taken MT-6548 before
  • Subjects with current conditions or histories of drug or food allergies
  • Subjects with below18.5 kg/m2, BMI above 25.0 kg/m2 or body weight below 50.0 kg at the screening test
  • Subjects who have undergone or plasma donation 2 weeks prior to the consent
  • Subjects who have undergone blood donation or blood draw of 400 mL or above within 12 weeks prior to the consent, or 200 mL or above within 4 weeks prior to the consent
  • Subjects who have undergone blood donation or blood draw of 800 mL or above within one year prior to the consent
  • Subjects who have undergone surgical operations that can affect gastrointestinal absorption of medication (appendectomy and hernioplasty do not meet this exclusion criterion)
  • Subjects with positive results for HBs antigen, syphilis serum reaction, antibody or antigen / antibody at the screening test
  • Subjects who are unwilling to consent to use from the beginning of study period to 90 days following the final dose of the study drug
  • Subjects who have participated in another clinical study and received study drugs within 12 weeks prior to consent, or within 5 times the half-life of the study drug (whichever is longer)
  • Subjects who have taken any medications except for the drug used for this clinical study within 7 days prior to the first dose of the study drug
  • Subjects who have had supplements within 7 days prior to the first dose of the study drug
  • Subjects who have had apples, citrus fruits such as grapefruits or any food products that contain apples or citrus fruits within 7 days prior to the first dose of the study drug
  • Subjects who have had food products which contain St John's Wort within 2 weeks prior to the first dose of the study drug
Terms in these criteria, in plain language(5)

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.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

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.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

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.

05

Study design

Phase
Phase 3
Primary purpose
Other
Allocation
Randomized
Intervention model
Crossover assignment
Masking
None (open label)
Enrollment
61 participants (actual)

Study arms

  • Experimental
    Cohort 1

    Subject will receive MT-6548 on Day 1, 4, and 7. Subject will receive Iron supplement A on Day 1, 4, or 7. Subject will receive Iron supplement B on Day 1, 4, or 7.

    Drug: MT-6548 · Drug: Iron supplement A · Drug: Iron supplement B

  • Experimental
    Cohort 2

    Subject will receive MT-6548 on Day 1 and 4. Subject will receive Iron supplement C on Day 1 or 4.

    Drug: MT-6548 · Drug: Iron supplement C

  • Experimental
    Cohort 3

    Subject will receive MT-6548 on Day 1 and 4. Subject will receive Iron supplement D on Day 1 or 4.

    Drug: MT-6548 · Drug: Iron supplement D

Interventions

  • Oral tablet

    Also known as: vadadustat, AKB-6548

  • DrugIron supplement A

    Oral tablet

  • DrugIron supplement B

    Oral tablet

  • DrugIron supplement C

    Oral tablet

  • DrugIron supplement D

    Oral tablet

06

What researchers measure

Primary outcomes

  1. Area Under the Plasma Concentration-time Curve From Time Zero to Infinity(AUC0-∞) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  2. Maximum Plasma Concentration (Cmax) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  3. Time to Reach Maximum Plasma Concentration (Tmax) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  4. Area Under the Plasma Concentration-time Curve From Time Zero Until the Last Quantifiable Concentration (AUC0-last) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  5. Mean Residence Time From Zero to Infinity (MRT0-∞) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  6. Apparent Terminal Elimination Rate Constant (Kel) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

  7. Terminal Elimination Half-life (t1/2) of Unchanged MT-6548

    Time frame: Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)

07

Results

Posted May 18, 2021

Participant flow

Participant flow — Overall Study
MilestoneCohort 1Cohort 2Cohort 3
Started212020
Completed202020
Not completed100
Withdrew: Withdrawal by subject100

Outcome measures

PrimaryArea Under the Plasma Concentration-time Curve From Time Zero to Infinity(AUC0-∞) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · ug*h/mL
Area Under the Plasma Concentration-time Curve From Time Zero to Infinity(AUC0-∞) of Unchanged MT-6548
ug*h/mLCohort 1Cohort 2Cohort 3
MT-6548105.3 ± 17.0100.2 ± 12.4129.3 ± 18.1
MT-6548+Iron supplement A49.2 ± 16.9——
MT-6548+Iron supplement B37.2 ± 19.5——
MT-6548+Iron supplement C—47.7 ± 13.9—
MT-6548+Iron supplement D——16.0 ± 10.7
PrimaryMaximum Plasma Concentration (Cmax) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · ug/mL
Maximum Plasma Concentration (Cmax) of Unchanged MT-6548
ug/mLCohort 1Cohort 2Cohort 3
MT-654814.5 ± 2.6115.5 ± 2.8327.1 ± 5.93
MT-6548+Iron supplement A7.76 ± 3.93——
MT-6548+Iron supplement B5.96 ± 3.09——
MT-6548+Iron supplement C—9.37 ± 3.21—
MT-6548+Iron supplement D——2.65 ± 1.95
PrimaryTime to Reach Maximum Plasma Concentration (Tmax) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Median · h
Time to Reach Maximum Plasma Concentration (Tmax) of Unchanged MT-6548
hCohort 1Cohort 2Cohort 3
MT-65483.00 (1.50 to 5.00)1.00 (0.50 to 5.00)2.00 (1.00 to 3.00)
MT-6548+Iron supplement A3.00 (1.00 to 6.00)——
MT-6548+Iron supplement B4.00 (1.00 to 5.00)——
MT-6548+Iron supplement C—1.00 (0.50 to 3.00)—
MT-6548+Iron supplement D——3.00 (0.50 to 5.00)
PrimaryArea Under the Plasma Concentration-time Curve From Time Zero Until the Last Quantifiable Concentration (AUC0-last) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · ug*h/mL
Area Under the Plasma Concentration-time Curve From Time Zero Until the Last Quantifiable Concentration (AUC0-last) of Unchanged MT-6548
ug*h/mLCohort 1Cohort 2Cohort 3
MT-6548100.4 ± 16.196.3 ± 11.7125 ± 17.2
MT-6548+Iron supplement A47 ± 16.6——
MT-6548+Iron supplement B36 ± 19.1——
MT-6548+Iron supplement C—46.4 ± 13.6—
MT-6548+Iron supplement D——14.9 ± 10.4
PrimaryMean Residence Time From Zero to Infinity (MRT0-∞) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · h
Mean Residence Time From Zero to Infinity (MRT0-∞) of Unchanged MT-6548
hCohort 1Cohort 2Cohort 3
MT-65488.23 ± 0.956.97 ± 0.826.56 ± 1.05
MT-6548+Iron supplement A8.06 ± 1.05——
MT-6548+Iron supplement B7.28 ± 0.98——
MT-6548+Iron supplement C—5.76 ± 0.86—
MT-6548+Iron supplement D——7.21 ± 1.47
PrimaryApparent Terminal Elimination Rate Constant (Kel) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · /h
Apparent Terminal Elimination Rate Constant (Kel) of Unchanged MT-6548
/hCohort 1Cohort 2Cohort 3
MT-65480.1314 ± 0.01810.1356 ± 0.02160.1354 ± 0.0194
MT-6548+Iron supplement A0.1302 ± 0.0146——
MT-6548+Iron supplement B0.1647 ± 0.0295——
MT-6548+Iron supplement C—0.1629 ± 0.031—
MT-6548+Iron supplement D——0.1518 ± 0.0499
PrimaryTerminal Elimination Half-life (t1/2) of Unchanged MT-6548
Time frame:
Up to Day 8 (Cohort 1), Up to Day 5 (Cohort 2, 3)
Reported as:
Mean · h
Terminal Elimination Half-life (t1/2) of Unchanged MT-6548
hCohort 1Cohort 2Cohort 3
MT-65485.38 ± 0.85.22 ± 0.755.23 ± 0.83
MT-6548+Iron supplement A5.39 ± 0.61——
MT-6548+Iron supplement B4.33 ± 0.71——
MT-6548+Iron supplement C—4.4 ± 0.86—
MT-6548+Iron supplement D——5.05 ± 1.63

Adverse events

Collected over Day 1 to 10 (cohort 1), Day 1 to 7 (cohort 2 and 3). Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Cohort 10/21 (0%)0/21 (0%)4/21 (19%)
Cohort 20/20 (0%)0/20 (0%)0/20 (0%)
Cohort 30/20 (0%)0/20 (0%)0/20 (0%)
Most frequent other events
Most frequent other events
EventCohort 1Cohort 2Cohort 3
Abdominal discomfortGastrointestinal disorders3/210/200/20
DiarrhoeaGastrointestinal disorders1/210/200/20

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)Cohort 1Cohort 2Cohort 3Total
<=18 years0000
Between 18 and 65 years21202061
>=65 years0000
Sex: Female, Male
Sex: Female, Male(Participants)Cohort 1Cohort 2Cohort 3Total
Female0000
Male21202061
Race/Ethnicity, Customized
Race/Ethnicity, Customized(Participants)Cohort 1Cohort 2Cohort 3Total
Japanese21202061
Other0000
08

Study locations

1 site
  • Research site
    Tokyo, Japan
09

References and documents

Publications

  • Kokado Y, Kawai K, Nanjo T, Kinoshita S, Kondo K. In Vitro and Clinical Pharmacokinetic Studies of the Effects of Iron-containing Agents on Vadadustat, an Oral Hypoxia-inducible Factor-Prolyl Hydroxylase Inhibitor. Clin Ther. 2021 Aug;43(8):1408-1418.e5. doi: 10.1016/j.clinthera.2021.06.013. Epub 2021 Sep 10. PubMed 34511184 ↗

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 6, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT03645863
Responsible party
Sponsor
First posted
Aug 24, 2018
Start date
Aug 27, 2018
Primary completion
Sep 30, 2018
Completion
Sep 30, 2018
Results posted
May 18, 2021
Last update
Apr 6, 2026

Study contacts

General Manager
study director · Tanabe Pharma Corporation

Oversight

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

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