A Phase 2 interventional study of Everolimus in Vascular Malformations, Arteriovenous Malformations and Venous Malformation, sponsored by Yonsei University. Not yet recruiting. Open to participants aged 1 Year and older. Per ClinicalTrials.gov, last updated 2026-03-17.
Sponsored by Yonsei University · Phase 2, Interventional, and Treatment
Background and Objectives Vascular anomalies are a heterogeneous group of disorders classified into vascular tumors and vascular malformations according to the ISSVA classification. Although most follow a benign course, a subset causes serious complications including organ dysfunction, chronic pain, thrombocytopenia, and hemorrhage. Kaposiform hemangioendothelioma (KHE) complicated by Kasabach-Merritt Phenomenon (KMP) carries a mortality rate of 14-24%. Surgical resection is the primary treatment when organ damage is not anticipated; however, when surgery is not feasible, pharmacologic therapy is considered. Agents such as interferon, corticosteroids, vincristine, cyclophosphamide, and propranolol have been used with variable efficacy, and no established therapy exists for patients refractory to these treatments.
The PI3K-Akt-mTOR and RAS-MEK-ERK pathways have been identified as key molecular mechanisms underlying vascular anomalies. Targeted therapies against these pathways are emerging, including anti-VEGF antibodies, PI3K/Akt inhibitors (e.g., alpelisib, miransertib), and mTOR inhibitors. Sirolimus has demonstrated clinical benefit in 50-80% of patients with vascular anomalies, with a 96% symptom response rate in KMP-associated vascular tumors. Everolimus, another mTOR inhibitor, is already approved and established for tuberous sclerosis-associated angiomyolipoma and SEGA in pediatric patients, with a well-characterized safety profile. Given its shared mechanism with sirolimus and emerging case reports supporting efficacy in KHE with KMP, this phase 2 study aims to evaluate the efficacy and safety of everolimus in patients with treatment-refractory vascular anomalies.
Study Design This is a single-center, open-label, uncontrolled phase 2 clinical trial enrolling 67 patients over 60 months from IRB approval, stratified into two cohorts: Cohort 1 (sirolimus-naïve, n=39) and Cohort 2 (prior sirolimus failure, n=28). Everolimus is administered orally at age- and CYP3A4/P-gp inducer-adjusted doses, with maintenance dosing titrated to a target trough level of 5-15 ng/mL. The primary endpoint is overall response rate (ORR) at 6 months. Secondary endpoints include toxicity per NCI CTCAE v4.0, ORR at 12 months, platelet recovery rate at 4 weeks (KMP patients), 1-year overall survival, and 3-year progression-free survival.
Eligibility Criteria
- Inclusion Criteria:
① Diagnosis per the 2014 ISSVA classification: Group 1 (hemangioendothelioma, tufted angioma): histologically confirmed tumor, OR Kasabach-Merritt Syndrome (histologically confirmed or histologic diagnosis not feasible) Group 2 (vascular tumors not in Group 1, or vascular malformations): histologically confirmed, OR radiologically diagnosed when biopsy is not feasible
Age ≥1 year
③ Failure of at least one prior therapy (e.g., vincristine, corticosteroids, interferon), stratified as: Cohort 1: sirolimus-naïve Cohort 2: prior sirolimus failure
④ At least one measurable target lesion ≥1 cm in longest diameter per RECIST 1.1 on CT or MRI
ECOG Performance Score 0, 1, or 2
Documented allergy or hypersensitivity to everolimus
③ Inadequate organ function: Bone marrow: ANC \<1,000/µL or platelets \<75,000/µL Renal: serum creatinine >1.5×ULN; if >1.5×ULN, 24-hour creatinine clearance \<60 mL/min Hepatic: total bilirubin >1.5×ULN or ALT >3.0×ULN
KMP associated with vascular tumors or malformations is not an exclusion criterion, including: thrombocytopenia (\<100,000/µL), hypofibrinogenemia, anemia (Hb \<8 g/dL), consumptive coagulopathy, or overlying skin changes (edema, warmth, erythema, purplish/dark discoloration)
Uncontrolled hyperlipidemia (fasting cholesterol >300 mg/dL or triglycerides >2.5×ULN)
Uncontrolled diabetes (fasting glucose >1.5×ULN)
Active uncontrolled infection
Hepatitis B (HBsAg positive) or hepatitis C (anti-HCV positive)
Known HIV infection (positive serology)
Clinically significant symptomatic pulmonary dysfunction; PFTs and room air SpO₂ performed if clinically indicated; exclusion if FEV₁ ≤70% or DLCO ≤70% of predicted (assessed in patients ≥8 years) ⑪ Prior solid organ or hematopoietic stem cell transplantation (bone marrow, liver, kidney, lung, or heart) ⑫ Concomitant investigational agents (e.g., mTOR inhibitors: sirolimus, temsirolimus)
⑬ Concurrent chemotherapy (e.g., mTOR inhibitors: sirolimus, temsirolimus)
Treatment
Everolimus is administered orally with doses adjusted by age and concomitant CYP3A4/P-gp inducer use:
-Starting dose: Age \<10 years: 6.0 mg/m²/day (9.0 mg/m²/day with CYP3A4/P-gp inducers) Age 10 to \<18 years: 5.0 mg/m²/day (8.0 mg/m²/day with CYP3A4/P-gp inducers) Age ≥18 years: 3.0 mg/m²/day (5.0 mg/m²/day with CYP3A4/P-gp inducers)
-Maintenance dose: Adjusted to achieve a target trough level of 5-15 ng/mL
Endpoints
- Primary endpoint: Overall response rate (ORR) at 6 months
- Secondary endpoints: Toxicity assessment per NCI CTCAE v4.0 ORR at 12 months Rate of platelet recovery at 4 weeks (KMP patients)
1-year overall survival (OS) 3-year progression-free survival (PFS)
92 studies on the registry are indexed under Arteriovenous Malformations; 29 are open to participants now.
This study's planned enrollment of 67 is above the median of 43 across 47 interventional studies indexed under Arteriovenous Malformations.
Browse Arteriovenous Malformations studies →Yonsei University is the lead sponsor of 1,418 studies on the registry; 241 are open to participants now.
Compared within Arteriovenous Malformations, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Vascular Malformations. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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.
① Diagnosis per the 2014 ISSVA classification: Group 1 (hemangioendothelioma, tufted angioma): confirmed tumor, OR Kasabach-Merritt Syndrome (histologically confirmed or histologic diagnosis not feasible) Group 2 (vascular tumors not in Group 1, or vascular malformations): histologically confirmed, OR radiologically diagnosed when is not feasible
Age ≥1 year ③ Failure of at least one prior therapy (e.g., vincristine, , interferon), stratified as: Cohort 1: sirolimus-naïve Cohort 2: prior sirolimus failure
At least one measurable target lesion ≥1 cm in longest diameter per 1.1 on CT or MRI
Exclusion Criteria:
Pregnancy or breastfeeding ( must use adequate )
Documented allergy or to everolimus
③ Inadequate organ function: Bone marrow: ANC \<1,000/µL or \<75,000/µL Renal: serum creatinine >1.5×; if >1.5×ULN, 24-hour \<60 mL/min Hepatic: total >1.5×ULN or >3.0×ULN
KMP associated with vascular tumors or malformations is not an exclusion criterion, including: thrombocytopenia (\<100,000/µL), hypofibrinogenemia, anemia ( \<8 g/dL), consumptive coagulopathy, or overlying skin changes (edema, warmth, erythema, purplish/dark discoloration)
Uncontrolled hyperlipidemia (fasting cholesterol >300 mg/dL or triglycerides >2.5×ULN)
Uncontrolled diabetes (fasting glucose >1.5×ULN)
Active uncontrolled infection
(HBsAg positive) or (anti-HCV positive) ⑨ Known infection (positive serology)
symptomatic pulmonary dysfunction; PFTs and room air SpO₂ performed if clinically indicated; exclusion if ≤70% or DLCO ≤70% of predicted (assessed in patients ≥8 years)
⑪ Prior solid organ or hematopoietic stem cell transplantation (bone marrow, liver, kidney, lung, or heart)
⑫ Concomitant agents (e.g., mTOR inhibitors: sirolimus, temsirolimus)
⑬ Concurrent chemotherapy (e.g., mTOR inhibitors: sirolimus, temsirolimus)
⑭ Concurrent other not meeting eligibility criteria
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.
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
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.
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.
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.
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.
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.
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 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.
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.
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).
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
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.
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.
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.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
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.
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.
Histologically or cytologically confirmed
The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).
Your pathology report is the document that shows this.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
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.
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
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.
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.
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.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
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.
Everolimus administered orally, dose adjusted by age and concomitant CYP3A4/P-gp inducer use. Target trough level: 5-15 ng/mL.
Drug: Everolimus
Everolimus (dose varies by age and concomitant use of CYP3A4/P-gp inducers) -Starting dose: Age \<10 years: 6.0 mg/m²/day (9.0 mg/m²/day with CYP3A4/P-gp inducers) Age 10 to \<18 years: 5.0 mg/m²/day (8.0 mg/m²/day with CYP3A4/P-gp inducers) Age ≥18 years: 3.0 mg/m²/day (5.0 mg/m²/day with CYP3A4/P-gp inducers) -Maintenance dose: Adjusted to achieve a target trough level of 5-15 ng/mL
Overall Response Rate (ORR)
ORR is defined as the proportion of patients achieving complete response (CR) or partial response (PR) per RECIST 1.1 criteria on CT or MRI at 6 months from treatment initiation.
Time frame: 6 months from treatment initiation
Overall Response Rate (ORR)
ORR is defined as the proportion of patients achieving complete response (CR) or partial response (PR) per RECIST 1.1 criteria on CT or MRI at 6 months from treatment initiation. ORR is defined as the proportion of patients achieving complete response (CR) or partial response (PR) per RECIST 1.1 criteria on CT or MRI at 6 months from treatment initiation. ORR is defined as the proportion of patients achieving complete response (CR) or partial response (PR) per RECIST 1.1 criteria on CT or MRI at 6 months from treatment initiation.
Time frame: 12 months from treatment initiation
Overall Survival (OS)
Proportion of patients alive at 1 year from treatment initiation
Time frame: 12 months from treatment initiation
Overall Response Rate (ORR)
ORR is defined as the proportion of patients achieving complete response (CR) or partial response (PR) per RECIST 1.1 criteria on CT or MRI at 6 months from treatment initiation.
Time frame: 12 months from treatment initiation
Toxicity
Incidence and severity of adverse events assessed per NCI CTCAE v4.0
Time frame: Throughout treament period (every 4 weeks)
Platelet Recovery Rate at 4 weeks (KMP patients)
4 weeks from treatment initiation
Time frame: Rate of platelet recovery to ≥100,000/µL at 4 weeks from treatment initiation, assessed in patients with Kasabach-Merritt Phenomenon at enrollment
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
Start is estimated for Apr 2026; primary completion for Oct 2030, 54 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Everolimus