Skip to content

Study of Pegloticase (KRYSTEXXA®) Plus Methotrexate in Patients With Uncontrolled Gout

A Multicenter, Efficacy and Safety Study of Methotrexate to Increase Response Rates in Patients With Uncontrolled Gout Receiving KRYSTEXXA® (Pegloticase) (MIRROR Open-Label [OL])

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03635957
Acronym
MIRROR OL
Enrollment
14
Registered
2018-08-17
Start date
2018-09-26
Completion date
2020-10-26
Last updated
2024-06-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Gout

Keywords

gout, uncontrolled gout

Brief summary

The overall objective of the study is to assess the efficacy, safety, tolerability, and pharmacokinetics (PK) of the concomitant use of pegloticase with methotrexate (MTX) to enhance the response rate seen with pegloticase alone in adults with uncontrolled gout.

Detailed description

The study design will include: 1) up to a 2-week Screening Period (screening should be complete within 2 weeks prior to Week -4), 2) a 4-week MTX Run in Period (Week - 4 through Day 1); 3) a 52-week Pegloticase + IMM (immunomodulator), (Pegloticase + MTX) Period 4) a Safety Follow-up (Phone/Email/Site Visit) and 5) a 3 and 6 month Post Treatment Follow-up. Study acquired from Horizon in 2024.

Interventions

BIOLOGICALPegloticase

pegloticase administered intravenously (IV)

DRUGMethotrexate (MTX)

oral MTX

DRUGStandard Gout Flare Prophylaxis

It is required that before a subject begins the Pegloticase + IMM Period, he or she has been taking at least one protocol standard gout flare prophylaxis regimen (i.e. colchicine and/or nonsteroidal anti-inflammatory drugs and/or low-dose prednisone ≤10 mg/day) for ≥1 week before the first dose of pegloticase and continues flare prophylaxis per American College of Rheumatology guidelines \[Khanna D et al.2012\] for the greater of 1) 6 months, 2) 3 months after achieving target serum urate (sUA \< 6 mg/dL) for patients with no tophi detected on physical exam, or 3) 6 months after achieving target serum urate (sUA \< 5 mg/dL) for patients with one or more tophi detected on initial physical exam that have since resolved.

DRUGInfusion Reaction (IR) Prophylaxis

For IR prophylaxis, fexofenadine (60 mg or 180 mg orally based on the Principal Investigator's discretion) will be taken the day before each infusion; fexofenadine (60 mg or 180 mg orally based on the Principal Investigator's discretion) and acetaminophen (1000 mg orally) will be taken the morning of each infusion; and methylprednisolone (125 mg IV) given over the infusion duration 10-30 minutes (recommended) or hydrocortisone (200 mg IV) will be administered immediately prior to each infusion.

DIETARY_SUPPLEMENTFolic Acid

Subjects will also take folic acid 1 mg orally every day beginning at Week -4 (the start of MTX) and continuing until prior to the Week 52 Visit.

Sponsors

Amgen
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

1. Willing and able to give informed consent. 2. Willing and able to comply with the prescribed treatment protocol and evaluations for the duration of the study. 3. Adult men or women ≥18 to ≤65 years of age. 4. Women of childbearing potential (including those with an onset of menopause \<2 years prior to screening, non-therapy-induced amenorrhea for \<12 months prior to screening, or not surgically sterile \[absence of ovaries and/or uterus\]) must have negative serum/urine pregnancy tests during the Screening/(methotrexate) MTX Run in Period; participants must agree to use 2 reliable forms of contraception during the study, one of which is recommended to be hormonal, such as an oral contraceptive. Hormonal contraception must be started ≥1 full cycle prior to Week -4 (start of MTX dosing) and continue for 30 days after the last dose of pegloticase or at least one ovulatory cycle after the last dose of MTX (whichever is the longest duration after the last dose of pegloticase or MTX). Highly effective contraceptive methods (with a failure rate \<1% per year), when used consistently and correctly, include implants, injectables, combined oral contraceptives, some intrauterine devices, sexual abstinence, or vasectomized partner. 5. Men who are not vasectomized must not impregnant their female partner during the study and for at least 3 months after the last dose of MTX. 6. Hyperuricemia at the Screening, Week -4, or Week -2 Visit of the Screening/MTX Run in Period, as documented by sUA ≥6 mg/dL. 7. Uncontrolled gout, defined as meeting the following criteria: serum uric acid (sUA) ≥6 mg/dL prior to entry into the pegloticase +IMM Period (any laboratory tests during screening up to and including during the MTX Run in Period) and at least 1 of the following: inability to maintain sUA \<6 mg/dL on other urate-lowering therapy; intolerable side effects associated with current urate-lowering therapy; functionally limiting tophaceous deposits (including those detected clinically or by dual-energy computed tomography \[DECT\] imaging) 8. Able to tolerate MTX 15 mg for 4 weeks during the MTX Run-in Period prior to the first dose of pegloticase.

Exclusion criteria

1. Weight \>160 kg (352 pounds). 2. Any serious acute bacterial infection, unless treated and completely resolved with antibiotics at least 2 weeks prior to the Week -4 Visit of the MTX Run-in Period. 3. Severe chronic or recurrent bacterial infections, such as recurrent pneumonia or chronic bronchiectasis. 4. Current immunocompromised condition, including current or chronic treatment with systemic immunosuppressive agents, including prednisone \>10 mg/day or equivalent dose of other corticosteroid. 5. History of any transplant surgery requiring maintenance immunosuppressive therapy. 6. Known history of hepatitis B virus surface antigen positivity or hepatitis B DNA positivity. 7. Known history of hepatitis C virus RNA positivity. 8. Human immunodeficiency virus (HIV) positivity (tested at the Screening Visit). 9. Glucose-6-phosphate dehydrogenase (G6PD) deficiency (tested at the Screening Visit). 10. Severe chronic renal impairment (glomerular filtration rate \<25 mL/min/1.73 m\^2) or currently on dialysis. 11. Non-compensated congestive heart failure or hospitalization for congestive heart failure within 3 months of the Screening Visit, uncontrolled arrhythmia, treatment for acute coronary syndrome (myocardial infarction or unstable angina), or uncontrolled blood pressure (\>160/100 mmHg) at the end of the Screening/MTX Run-in Period. 12. Pregnant, planning to become pregnant, breastfeeding, planning to impregnant female partner, or not on an effective form of birth control, as determined by the Investigator. 13. Prior treatment with pegloticase (KRYSTEXXA®), another recombinant uricase (rasburicase), or concomitant therapy with a polyethylene glycol-conjugated drug. 14. Known allergy to pegylated products or history of anaphylactic reaction to a recombinant protein or porcine product. 15. Contraindication to MTX treatment or MTX treatment considered inappropriate. 16. Known intolerance to MTX. 17. Receipt of an investigational drug within 4 weeks or 5 half-lives, whichever is longer, prior to MTX administration at Week -4 or plans to take an investigational drug during the study. 18. Current liver disease, as determined by alanine transaminase or aspartate transaminase levels \>3 times upper limit of normal at the Screening Visit. 19. Currently receiving systemic or radiologic treatment for ongoing cancer, excluding non melanoma skin cancer. 20. History of malignancy within 5 years other than non-melanoma skin cancer or in situ carcinoma of cervix. 21. Uncontrolled hyperglycemia with a plasma glucose value \>240 mg/dL at screening that is not subsequently controlled by the end of the Screening/MTX Run-in Period. 22. Diagnosis of osteomyelitis. 23. Known history of hypoxanthine-guanine phosphoribosyl-transferase deficiency, such as Lesch-Nyhan and Kelley-Seegmiller syndrome. 24. Unsuitable candidate for the study, based on the opinion of the Investigator (e.g., cognitive impairment), such that participation might create undue risk to the participant or interfere with the participant's ability to comply with the protocol requirements or complete the study. 25. Alcohol use in excess of 3 alcoholic beverages per week. 26. Currently receiving allopurinol and unable to discontinue medication 7 days prior to MTX dosing at Week -4 and unable to discontinue treatment during the duration of the study.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 6Month 6 (Weeks 20, 22, and 24)Serum uric acid (sUA \< 6 mg/dL) responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 6 (Weeks 20, 22, and 24). Month 6 includes pre-infusion and post-infusion sUA assessments at Week 20, pre-infusion and post-infusion sUA assessments at Week 22, pre-infusion assessments at Week 24, and unscheduled sUA assessments between Week 20 and Week 24.

Secondary

MeasureTime frameDescription
Percentage of Serum Uric Acid (sUA < 6 mg/dL) Overall RespondersMonth 3 and Month 6 combined (Weeks 10, 12, 14, 20, 22, and 24)Serum uric acid (sUA \< 6 mg/dL) overall responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 3 and Month 6 (Weeks 10, 12, 14, 20, 22, and 24) combined. Participants with more than one sUA result in Month 3 and Month 6 are considered responders if a participant's weighted proportion of hours that sUA is \< 6 mg/dL is greater than or equal to 80%. Participants with the proportion of hours less than 80% are counted as non-responders. Participants with only one value in Month 3 and Month 6 are considered overall responders if they are considered responders in both Month 3 and Month 6.
Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 3Month 3 (Weeks 10, 12, and 14)Serum uric acid (sUA \< 5 mg/dL) responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 3. Month 3 includes pre-infusion and post-infusion sUA assessments at Week 10, pre-infusion and post-infusion sUA assessments at Week 12, pre-infusion assessments at Week 14, and unscheduled assessments between Week 10 and Week 14 pre-infusion.
Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 3Month 3 (Weeks 10, 12, and 14)Serum uric acid (sUA \< 6 mg/dL) responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 3 (Weeks 10, 12, and 14). Month 3 includes pre-infusion and post-infusion sUA assessments at Week 10, pre-infusion and post-infusion sUA assessments at Week 12, pre-infusion assessments at Week 14, and unscheduled assessments between Week 10 and Week 14 pre-infusion.
Percentage of Serum Uric Acid (sUA < 5 mg/dL) Overall RespondersMonth 3 and Month 6 combined (Weeks 10, 12, 14, 20, 22, and 24)Serum uric acid (sUA \< 5 mg/dL) overall responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 3 and Month 6 (Weeks 10, 12, 14, 20, 22, and 24) combined. Participants with more than one sUA result in Month 3 and Month 6 are considered responders if a participant's weighted proportion of hours that sUA is \< 6 mg/dL is greater than or equal to 80%. Participants with the proportion of hours less than 80% are counted as non-responders. Participants with only one value in Month 3 and Month 6 are considered overall responders if they are considered responders in both Month 3 and Month 6.
Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Baseline (defined as the last measurement taken prior to the first infusion of pegloticase in the pegloticase + IMM period), Pre- and Post-Infusion at Weeks 14, 24, 36 and Week 52The mean change from baseline is based on observed values in participants remaining on treatment at given time point. For sUA values less than the lower limit of detection (up to 1.5 mg/dL), 0 is used in the analysis.
Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 6Month 6 (Weeks 20, 22, and 24)Serum uric acid (sUA \< 5 mg/dL) responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 6. Month 6 includes pre-infusion and post-infusion sUA assessments at Week 20, pre-infusion and post-infusion sUA assessments at Week 22, pre-infusion assessments at Week 24, and unscheduled sUA assessments between Week 20 and Week 24.

Countries

United States

Participant flow

Pre-assignment details

One participant was dosed with methotrexate (MTX) in the Run-In Period (MTX tolerance period) but was lost to follow up prior to the per protocol enrollment at Day 1. This participant was a screen failure but is included in the Run-in period data (including safety).

Participants by arm

ArmCount
Pegloticase With Methotrexate (MTX)
Run-In Period: oral MTX at a dose of 15 mg weekly for 4 weeks prior to the first dose of pegloticase. Pegloticase + IMM Period: pegloticase 8 mg administered IV every 2 weeks from Day 1 through the Week 50 Visit for a total of 26 infusions. MTX 15 mg weekly on the same day each week, within 1 to 3 days prior to each pegloticase infusion and one additional weekly dose after the last infusion.
14
Total14

Withdrawals & dropouts

PeriodReasonFG000
Pegloticase + IMM PeriodLack of Efficacy3
Run-In PeriodLost to Follow-up1

Baseline characteristics

CharacteristicPegloticase With Methotrexate (MTX)
Age, Continuous49.3 years
STANDARD_DEVIATION 8.66
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
13 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
2 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
12 Participants
Serum Uric Acid (sUA)9.16 mg/dL
STANDARD_DEVIATION 2.486
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
14 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 150 / 14
other
Total, other adverse events
10 / 1514 / 14
serious
Total, serious adverse events
0 / 151 / 14

Outcome results

Primary

Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 6

Serum uric acid (sUA \< 6 mg/dL) responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 6 (Weeks 20, 22, and 24). Month 6 includes pre-infusion and post-infusion sUA assessments at Week 20, pre-infusion and post-infusion sUA assessments at Week 22, pre-infusion assessments at Week 24, and unscheduled sUA assessments between Week 20 and Week 24.

Time frame: Month 6 (Weeks 20, 22, and 24)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 678.6 percentage of participants
Secondary

Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52

The mean change from baseline is based on observed values in participants remaining on treatment at given time point. For sUA values less than the lower limit of detection (up to 1.5 mg/dL), 0 is used in the analysis.

Time frame: Baseline (defined as the last measurement taken prior to the first infusion of pegloticase in the pegloticase + IMM period), Pre- and Post-Infusion at Weeks 14, 24, 36 and Week 52

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase. Participants with a measurement at given time point.

ArmMeasureGroupValue (MEAN)Dispersion
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 14 - pre-infusion-9.27 mg/dLStandard Deviation 2.81
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 14 - post-infusion-9.31 mg/dLStandard Deviation 2.959
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 24 - pre-infusion-9.27 mg/dLStandard Deviation 2.81
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 24 - post-infusion-9.48 mg/dLStandard Deviation 4.135
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 36 - pre-infusion-8.13 mg/dLStandard Deviation 3.975
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 36 - post-infusion-9.41 mg/dLStandard Deviation 3.293
Pegloticase With Methotrexate (MTX)Mean Change in sUA From Pegloticase Baseline to Weeks 14, 24, 36, 52Change at Week 52-8.15 mg/dLStandard Deviation 4.086
Secondary

Percentage of Serum Uric Acid (sUA < 5 mg/dL) Overall Responders

Serum uric acid (sUA \< 5 mg/dL) overall responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 3 and Month 6 (Weeks 10, 12, 14, 20, 22, and 24) combined. Participants with more than one sUA result in Month 3 and Month 6 are considered responders if a participant's weighted proportion of hours that sUA is \< 6 mg/dL is greater than or equal to 80%. Participants with the proportion of hours less than 80% are counted as non-responders. Participants with only one value in Month 3 and Month 6 are considered overall responders if they are considered responders in both Month 3 and Month 6.

Time frame: Month 3 and Month 6 combined (Weeks 10, 12, 14, 20, 22, and 24)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 5 mg/dL) Overall Responders78.6 percentage of participants
Secondary

Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 3

Serum uric acid (sUA \< 5 mg/dL) responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 3. Month 3 includes pre-infusion and post-infusion sUA assessments at Week 10, pre-infusion and post-infusion sUA assessments at Week 12, pre-infusion assessments at Week 14, and unscheduled assessments between Week 10 and Week 14 pre-infusion.

Time frame: Month 3 (Weeks 10, 12, and 14)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 378.6 percentage of participants
Secondary

Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 6

Serum uric acid (sUA \< 5 mg/dL) responders are defined as participants achieving and maintaining sUA \< 5 mg/dL for at least 80% of the time during Month 6. Month 6 includes pre-infusion and post-infusion sUA assessments at Week 20, pre-infusion and post-infusion sUA assessments at Week 22, pre-infusion assessments at Week 24, and unscheduled sUA assessments between Week 20 and Week 24.

Time frame: Month 6 (Weeks 20, 22, and 24)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 5 mg/dL) Responders During Month 678.6 percentage of participants
Secondary

Percentage of Serum Uric Acid (sUA < 6 mg/dL) Overall Responders

Serum uric acid (sUA \< 6 mg/dL) overall responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 3 and Month 6 (Weeks 10, 12, 14, 20, 22, and 24) combined. Participants with more than one sUA result in Month 3 and Month 6 are considered responders if a participant's weighted proportion of hours that sUA is \< 6 mg/dL is greater than or equal to 80%. Participants with the proportion of hours less than 80% are counted as non-responders. Participants with only one value in Month 3 and Month 6 are considered overall responders if they are considered responders in both Month 3 and Month 6.

Time frame: Month 3 and Month 6 combined (Weeks 10, 12, 14, 20, 22, and 24)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 6 mg/dL) Overall Responders78.6 percentage of participants
Secondary

Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 3

Serum uric acid (sUA \< 6 mg/dL) responders are defined as participants achieving and maintaining sUA \< 6 mg/dL for at least 80% of the time during Month 3 (Weeks 10, 12, and 14). Month 3 includes pre-infusion and post-infusion sUA assessments at Week 10, pre-infusion and post-infusion sUA assessments at Week 12, pre-infusion assessments at Week 14, and unscheduled assessments between Week 10 and Week 14 pre-infusion.

Time frame: Month 3 (Weeks 10, 12, and 14)

Population: Modified Intent to Treat Population: all enrolled participants who received at least 1 dose of pegloticase.

ArmMeasureValue (NUMBER)
Pegloticase With Methotrexate (MTX)Percentage of Serum Uric Acid (sUA < 6 mg/dL) Responders During Month 378.6 percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 17, 2026