ClinicalTrials.gg
CompletedNCT04677777HEMERA-1Updated Nov 14, 2025

Safety Study of PP-007 in Subjects With Acute Ischemic Stroke

A Phase 1 interventional study of PP-007 (Two doses administered 24±6 hours apart) + SOC (IVT or MT or IVT+MT) in Acute Ischemic Stroke, sponsored by Prolong Pharmaceuticals. Completed at 8 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-11-14.

Sponsored by Prolong Pharmaceuticals · Phase 1, Interventional, and Treatment

From the registry’s dates

  • Primary completion was Feb 2025, 1 year 8 months ago, and no results have been posted to the registry.
Phase
Phase 1
Study type
Interventional
Enrollment
24
Allocation
Not applicable
Ages
18 Years and older
Sex
All
01

Where this study stands

Counted across the records on this site · 2026-11-12

Among 480 studies in Ischemic Stroke with a site in United States — 122 open to participants now, 146 under way, 13 of them phase 3. Ischemic Stroke · United States.

Enrollment
261st of 364
24 · median 66
Started
2024
with 29 others
Phase 1
37 of 480
4 open now
Registered
284th of 480
by date

Among the 480 studies in Ischemic Stroke with a site in United States, this one is the 261st largest by enrollment of the 364 interventional ones that give a count, is one of 30 that started in 2024, is one of 37 in phase 1, and was the 284th registered.

Ischemic Stroke

2,617 studies on the registry are indexed under Ischemic Stroke; 976 are open to participants now.

Browse Ischemic Stroke studies →

Open to participants now

122 of the 480 studies in Ischemic Stroke with a site in United States are open now. Recruiting first, the newest first:

117 more — sign in →

All 122 open studies →

A study can be open while its sites in United States have not opened yet or have stopped. Only those recruiting at a site in United States →

Who these studies take

Of the 661 Ischemic Stroke studies recruiting now, 396 (60%) set no upper age limit and 62 (9%) stop at 75 or younger; 26 take children under 18; 42 take healthy volunteers.

This study: 18 Years and older · all sexes · no healthy volunteers.

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Watch this landscapeDownload CSVNarrow it in search →With an account: a weekly mail of what changed among 480 studies in Ischemic Stroke with a site in United States, or all of them as a file.
02

Study summary

The HEMERA-1 Extension (Part III) is a prospective, open-label, multicenter study to evaluate safety of two doses of PP-007 in Acute Ischemic Stroke (AIS) subjects receiving Intravenous Thrombolysis (IVT) or mechanical thrombectomy (MT) or IVT+MT as standard of care (SOC). Subjects will receive two doses of PP-007 infusion 24 ± 6 hours apart in addition to the site-specific SOC protocol. PP-007 is PEGylated bovine carboxyhemoglobin and will be administered via IV infusion. The effects on collateral flow, infarct size and functional outcomes will be evaluated.

Read the detailed description

Part III of the HEMERA study evaluates safety after extended drug exposure of PP-007 in subjects with AIS. Subjects would receive two PP-007 doses administered 24±6 hours apart, in addition to the site's SOC protocol of IVT or MT or IVT+MT. PP-007 is PEGylated bovine carboxyhemoglobin and will be administered via IV infusion. The effects on collateral flow, infarct size and functional outcomes (NIHSS and mRS) will also be evaluated. Other measures include assessment of plasma concentration of PP-007.

03

Conditions studied

  • Acute Ischemic Stroke

Keywords

  • Stroke
  • Thrombectomy
  • Intravenous Thrombolysis
  • NIHSS, mRS, ASPECTS
04

Who can participate

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

Eligibility criteria

Inclusion Criteria:

  1. Subject or subject's LAR has provided .
  2. ≥18 years of age.
  3. If the patient were to receive MT, patient must have a history of last seen well ≤ 24 hours prior to start of MT
  4. If the patient were to receive IVT, patient must have a history of last seen well ≤ 4.5 hours prior to start of IVT or as per Institution SOC Note: Onset is defined as the time point when symptoms first began, or if unknown, the last time point when the subject reported or was observed having normal (baseline) neurological function.
  5. AIS patient with ASPECTS ≥ 3 to 10
  6. AIS patient with of 90 days, as determined by the investigator
  7. Patient with disabling stroke defined as baseline NIHSS ≥ 6 prior to IP administration
  8. mRS ≤ 2 (pre-morbid), prior to onset of symptoms (self-reported or family/caregiver reported)
  9. At the time of stroke, patient must be living in their own home, apartment or seniors lodge where no nursing care/support is required
  10. Subject and caregiver are available for protocol-required follow-up visits
  11. and pregnancy:

    1. Male subjects, and females of (subjects and female partners of male subjects who are ovulating, premenopausal, and not surgically sterile) must use a highly effective method of contraception consistently and correctly during study participation and up to 90 days following PP-007 infusion.
    2. Highly effective methods of contraception are those that, either alone or in combination, result in a failure rate of \<1% per year when used consistently and correctly, including:

    i. Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation (i.e., oral, intravaginal, or transdermal).

    ii. Progesterone-only hormonal contraception associated with inhibition of ovulation (i.e., oral, injectable, or implantable).

    iii. Intrauterine device, intrauterine hormone-releasing system, or bilateral tubal occlusion.

    iv. Male sterilization performed more than six months prior to Screening. v. Sexual abstinence. c. Female subjects of non-childbearing potential must be either surgically sterile (hysterectomy, bilateral tubal ligation, salpingectomy, and/or bilateral oophorectomy at least 26 weeks before Screening) or , defined as spontaneous amenorrhea for at least 12 months.

    d. Male subjects must abstain from sperm donation during study participation and up to 90 days following PP-007 infusion.

    e. Female subjects of childbearing potential must have negative results for the pregnancy test at Screening/Baseline.

    Exclusion Criteria:

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  1. ASPECTS \< 3 on NCCT
  2. Multi-arterial territorial strokes (e.g. bilateral, anterior and posterior circulation)
  3. Evidence of symptomatic intracranial hemorrhage, including subarachnoid hemorrhage, on initial CTA/CTP, or history of intracranial hemorrhage within the last 30 days.
  4. Pre-existing neurological or psychiatric disease that would confound neurological or functional evaluations in the opinion of the Investigator.
  5. A seizure at stroke onset that precludes obtaining an accurate screening NIHSS and mRS assessment
  6. Clinical history, past imaging, or clinical judgment suggests that the intracranial occlusion is chronic
  7. History of severe head injury within 90 days of Baseline with residual neurological deficit at the time of AIS.
  8. heart disease including:

    a. Symptoms or evidence of acute myocardial infarction or unstable angina. b. Cardiac arrhythmia associated with hemodynamic instability. c. Heart failure ( Class III or IV) or known \<30%.

    d. ECG with second- or third-degree heart block in the absence of a permanent pacemaker.

  9. BP (systolic >200 and/or diastolic >120 mmHg).
  10. Confirmed diagnosis of septic embolus or bacterial endocarditis within the past six months.
  11. Aortic dissection.
  12. to radiographic imaging procedures including:

    a. Known to radiographic contrast agents. b. Known renal insufficiency precluding repeated contrast administration.

  13. Prior treatment (within the last 30 days) or planned concurrent treatment with an medication or device.
  14. Blood glucose \<50 mg/dL (2.78 mmol) or >400 mg/dL (22.20 mmol) that is not responsive to appropriate treatment at Baseline.
  15. Known bleeding disorder (e.g., coagulopathy or thrombocytopenia).

    a. count \<50,000/μL at Baseline b. Any anticoagulants within the previous 48 hours that leads to (International Normalization Ratio [INR]) ≥2.0 and/or activated partial thromboplastin time (aPTT) ≥40 sec at baseline.

    c. Any dual antiplatelet agents (e.g., aspirin plus clopidogrel) within the previous 48 hours that leads to Prothrombin Time (INR ≥ 2.0 and or aPTT ≥ 40 sec at baseline)

  16. Known history or current evidence of renal or hepatic disease including:

    1. Documented renal insufficiency (serum creatinine >3.0 × ).
    2. History of liver disease (i.e., [ALT] and/or Aspartate transaminase (AST) >2 × ULN and/or conjugated >1.5 mg/dL).

Note: A subject without history or current evidence of renal or hepatic disease does not require creatinine, ALT, AST, or bilirubin results to be available prior to enrollment.

17. Mass effect or intracranial mass on NCCT defined as:

  1. Significant mass effect with midline shift ≥8 mm.
  2. Evidence of intracranial mass (except for small non-clinically significant meningioma based on the Investigator's discretion).

    18. Employee of Prolong Pharmaceuticals or its designated clinical research organization or an employee or relative of the Investigator.

    19. Any condition or situation which may put the subject at significant risk, may confound the study results, or may interfere significantly with the subject's participation in the study in the opinion of the Investigator.

    20. Intracranial neoplasm, arteriovenous malformation, or aneurysm 21. Participation in another clinical trial investigating a drug, medical device, or a medical procedure in the 30 days preceding study inclusion Note: LVO and/or SVO will be allowed as long as the respective study subject meets the inclusion and exclusion criteria defined above.

    Inclusion/Exclusion criteria for 2nd PP-007 dose: Prior to administering the second dose of PP-007, the subject, must be evaluated for the following:

    Inclusion Criteria for 2nd dose:

    1. AIS patient with ASPECTS ≥ 3 to 10

    Exclusion Criteria for 2nd dose:

    1. Multi-arterial territorial strokes (e.g. bilateral, anterior and posterior circulation)
    2. Evidence of symptomatic intracranial hemorrhage, including subarachnoid hemorrhage, on NCCT or CTA/CTP.
    3. Clinically significant heart disease including:

a. Symptoms or ECG evidence of acute myocardial infarction or unstable angina. b. Cardiac arrhythmia associated with hemodynamic instability. c. Heart failure (New York Heart Association Class III or IV) or known ejection fraction \<30%.

d. ECG with second- or third-degree heart block in the absence of a permanent pacemaker.

4. Refractory BP (systolic >200 and/or diastolic >120 mmHg). 5. Confirmed diagnosis of septic embolus or bacterial endocarditis. 6. Aortic dissection. 7. Blood glucose \<50 mg/dL (2.78 mmol) or >400 mg/dL (22.20 mmol). 8. Known bleeding disorder (e.g., coagulopathy or thrombocytopenia).

a. Platelet count \<50,000/μL at Baseline b. For 2nd dose, patient fully anti-coagulated (heparinized) will be excluded (DBT prophylaxis is allowed) 9. Evidence of renal or hepatic disease including:

  1. Documented renal insufficiency (serum creatinine >3.0 × ULN).
  2. Documented liver disease (i.e., alanine transaminase [ALT] and/or Aspartate transaminase (AST) >2 × ULN and/or conjugated bilirubin >1.5 mg/dL).

Note: A subject without history or current evidence of renal or hepatic disease does not require creatinine, ALT, AST, or bilirubin results to be available prior to enrollment.

10. Mass effect or intracranial mass on NCCT defined as:

a. Significant mass effect with midline shift ≥8 mm. b. Evidence of intracranial mass (except for small non-clinically significant meningioma based on the Investigator's discretion).

11. Intracranial neoplasm, arteriovenous malformation, or aneurysm 12. Any condition or situation which may put the subject at significant risk, may confound the study results, or may interfere significantly with the subject's participation in the study in the opinion of the Investigator.

  1. Parenchymal hematoma (PH-1 and PH-2)
  2. Symptomatic intracranial hemorrhage
  3. Hemicraniectomy
  4. Midline shift ≥ 8 mm
  5. Mass effect
  6. Significant cerebral edema Note: LVO and/or SVO will be allowed as long as the respective study subject meets the inclusion and exclusion criteria defined above. The decision to administer the 2nd dose will be based on subject's safety and PI's discretion.
Terms in these criteria, in plain language(18)

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.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Life expectancy

The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.

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.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

ECG (electrocardiogram)

A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

LVEF (left ventricular ejection fraction)

The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.

Relapsed and refractory

Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

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.

INR, PT and aPTT (clotting tests)

Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.

Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

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.

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.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
24 participants (actual)

Study arms

  • Experimental
    PP-007 along with Standard of care (SOC)

    The study has only single arm, wherein, patients will receive two doses of PP-007 (24 ± 6 hours apart), along with the Standard-of-care (SOC) as per the site's medical practice. SOC is defined as Intravenous thrombolysis (IVT) or Mechanical Thrombectomy (MT) or both (IVT+MT).

    Biological: PP-007 (Two doses administered 24±6 hours apart) + SOC (IVT or MT or IVT+MT)

Interventions

  • BiologicalPP-007 (Two doses administered 24±6 hours apart) + SOC (IVT or MT or IVT+MT)

    Drug page: PEGylated carboxyhemoglobin bovine

    PP-007 is PEGylated carboxyhemoglobin. Eligible patients will receive two doses of PP-007 (at least 24 hours apart) to evaluate extended drug exposure along with MT and/or IVT (individually or together) as SOC to evaluate safety in AIS patients.

    Also known as: Sanguinate

06

What researchers measure

Primary outcomes

  1. Vital Signs

    Change from baseline in systolic and diastolic blood pressure in mm Hg

    Time frame: 90 days

  2. Heart-rate

    Change from baseline in heart-rate in bpm

    Time frame: 90 days

  3. 12-lead ECG

    Change from baseline in msec for QT, QTc, RR and PR intervals

    Time frame: 90 days

  4. Clinically significant change from baseline in Biochemical, hematological, coagulation and urinalysis measures

    Number of subjects with clinically significant change from baseline in Biochemical, hematological, coagulation and urinalysis measures

    Time frame: 90 days

  5. Cardiovascular Adverse Events (MI, myocardial injury, hypertension. hypertensive crisis, pulmonary hypertension) & Mortality

    Number of occurrences

    Time frame: 90 days

  6. Symptomatic intracranial hemorrhage

    Incidence of symptomatic intracranial hemorrhage, number of occurrences

    Time frame: 90 days

  7. Major Bleeding incidences

    Number of occurrences

    Time frame: 90 days

  8. Adverse Events

    Presence or absence

    Time frame: 90 days

  9. Bleeding requiring surgical intervention

    Number of occurrences

    Time frame: 90 days

  10. Bleeding requiring intravenous vasoactive drugs

    Number of occurrences

    Time frame: 90 days

  11. Intracranial hemorrhage

    Number of occurrences

    Time frame: 90 days

  12. Intraocular bleed compromising vision

    Number of occurrences

    Time frame: 90 days

  13. Fatal bleeding

    Number of occurrences

    Time frame: 90 days

  14. AESI, Blood pressure

    Number of events of systolic blood pressure \[SBP\] \>220 mmHg or diastolic blood pressure \[DBP\] \>120 mmHg

    Time frame: 90 days

  15. AESI, Liver panel

    Number of events of Liver enzymes elevation \>3.0 × Baseline or upper limit of normal \[ULN\]

    Time frame: 90 days

  16. AESI, neurological deterioration

    Number of occurrences of Neurological deterioration (≥4-point increase from Baseline in National Institutes of Health Stroke Scale (NIHSS).

    Time frame: 90 days

Secondary outcomes

  1. Clinical Activity, ASITN collateral score

    American Society of Interventional and Therapeutic Neuroradiology collateral score (CT Change from baseline in angiography \[CTA\] Score 0-4 pre- and post-dose

    Time frame: 90 days

  2. Clinical Activity

    Non-contrast computed tomography (NCCT 24 hours)

    Time frame: 90 days

  3. Clinical Activity, NIHSS and mRS

    Change from baseline in NIHSS and mRS score

    Time frame: 90 days

  4. Plasma Concentration of PP007

    Plasma PP007 concentration in mg/mL at end of infusion and 24 h post infusion

    Time frame: 24 hours

  5. Clinical Activity, eTICI

    Change from baseline in Expanded treatment in cerebral infarction (eTICI) score 2b or 3 post-thrombectomy change

    Time frame: 90 days

  6. Clinical Activity, infarct growth

    Predicted infarct growth for CT/CTP and collateral score

    Time frame: 90 days

07

Study locations

8 sites
  • Baptist Health Research Institute
    Jacksonville, Florida 32207, United States
  • Baptist Health Miami Cardiac & Vascular Institute (MCVI)
    Miami, Florida 33176, United States
  • Emory University School of Medicine
    Atlanta, Georgia 30303, United States
  • Saint Luke's Hospital
    Kansas City, Missouri 64111, United States
  • Mercy Health - St. Vincent Medical Center
    Toledo, Ohio 43608, United States
  • University of Oklahoma Health Sciences Center
    Oklahoma City, Oklahoma 73104, United States
  • Oregon Stroke Center at Oregon Health & Science University (OHSU)
    Portland, Oregon 97239, United States
  • UPMC Stroke Institute
    Pittsburgh, Pennsylvania 15213, United States
08

References and documents

Publications

  • Linfante I, Clark W, Haussen DC, Hanel R, Reshi R, Dabus G, Jubin R, Roshan MP, Belnap S, Nguyen TN, Grotta J, Wicks R, Cipolla MJ, Liebeskind DS, Nogueira RG. HEMERA 1 CarboxyHEMoglobin oxygEn delivery for Revascularization in Acute Stroke: A Prospective, Randomized Phase 1 Clinical Trial. Stroke Vasc Interv Neurol. 2024 Apr 23;4(4):e001246. doi: 10.1161/SVIN.123.001246. eCollection 2024 Jul. PubMed 41585378 ↗
09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Apr 2024 to primary completion in Feb 2025, 9 months.

Of 42 phase 1 interventional studies under Ischemic Stroke, half reached primary completion within 15 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 29. This study's 9 months is below that.

How these figures are worked out, and which studies are left out of them.

Registered
Nov 11, 2020
First posted
Dec 21, 2020
StartActual
Apr 24, 2024
Primary completionActual
Feb 20, 2025
CompletionActual
Feb 20, 2025
Last update
Nov 14, 2025
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Nov 14, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04677777
Lead sponsor
Prolong Pharmaceuticals
Responsible party
Sponsor
First posted
Dec 21, 2020
Start date
Apr 24, 2024
Primary completion
Feb 20, 2025
Completion
Feb 20, 2025
Last update
Nov 14, 2025

Study contacts

Kirsten Gruis, MD
study director · Prolong Pharmaceuticals, LLC

Oversight

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

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Studies of the drug tested here: PEGylated carboxyhemoglobin bovine

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