NCT00508989

Brief Summary

This study will determine whether niacin can improve blood flow in people with sickle cell disease, in which abnormal red blood cells interfere with blood flow to cause the disease symptoms. Niacin, a drug that has been used to increase HDL (good cholesterol) levels, improves blood flow in people without sickle cell disease. This study will see if it can do the same in people with the disease. Patients with sickle cell disease between 18 and 65 years of age may be eligible for this study. Candidates are screened with a medical history, physical examination, blood tests, echocardiogram and 6-minute walk test of exercise capacity. Participants have the following baseline blood flow studies:

  • Flow-mediated dilation (FMD): An ultrasound picture of the artery in the forearm is obtained. A blood pressure cuff is then placed on the upper arm and inflated for 5 minutes. After the pressure cuff is released, the ultrasound is repeated.
  • Peripheral artery tonometry (PAT): A sensor is placed on the subject s finger. The sensor puts pressure on the finger and measures blood flow.
  • Standard forearm blood flow test: Small tubes are placed in the artery of the forearm at the inside of the elbow. Saline is infused into one tube. Pressure cuffs are applied to the wrist and upper arm. A strain gauge (rubber band device) is placed around the forearm. When the cuffs are inflated, blood flows into the arm, stretching the strain gauge, and the flow measurement is recorded. Blood samples are collected from the tube in the artery to measure blood counts, proteins and other chemicals. At various times, small doses of the following drugs are administered through the tube in the vein:
  • Sodium nitroprusside causes blood vessels to dilate and increases blood flow to the heart.
  • Acetylcholine causes blood vessels to dilate and slows heart rate.
  • LNMMA decreases blood flow by blocking the production of nitric oxide. Blood flow is measured after each dose of the different drugs. There are rest periods between injections of the different drugs. Pictures of the forearm are taken during the studies using an infrared camera and computer.
  • Drug Treatment. Participants are assigned to take three 4-week courses of niacin or placebo. They return to the Clinical Center at the following intervals from the time they start the test drug for followup:
  • Weeks 2, 6 and 10: Brief medical history, review of medication side effects and blood tests.
  • Weeks 4 and 8: Physical examination, brief medical history, review of medication side effects and blood tests, repeat FMD and PAT blood flow studies and 6-minute walk test.
  • Week 12: Same as weeks 4 and 8 plus standard blood flow studies and echocardiogram.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
30

participants targeted

Target at P25-P50 for phase_2

Timeline
Completed

Started Jul 2007

Longer than P75 for phase_2

Geographic Reach
1 country

2 active sites

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

July 24, 2007

Completed
3 days until next milestone

First Submitted

Initial submission to the registry

July 27, 2007

Completed
3 days until next milestone

First Posted

Study publicly available on registry

July 30, 2007

Completed
3.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2010

Completed
5 years until next milestone

Study Completion

Last participant's last visit for all outcomes

December 24, 2015

Completed
Last Updated

September 10, 2020

Status Verified

December 24, 2015

Enrollment Period

3.4 years

First QC Date

July 27, 2007

Last Update Submit

September 3, 2020

Conditions

Keywords

AcetylcholineForearm Blood FlowHDLL-NMMASickle Cell AnemiaSickle Cell Disease

Outcome Measures

Primary Outcomes (1)

  • The Effect of niacin-ER on endothelial dysfunction in the sickle cell.

    12 weeks

Secondary Outcomes (1)

  • Effect of niacin therapy on HDL and apo A-I levels in subjects with sickle cell disease.

    12 weeks

Study Arms (2)

1

EXPERIMENTAL
Drug: Niacin-ERDrug: L-NMMADrug: Acetylcholine

2

PLACEBO COMPARATOR
Drug: Placebo

Interventions

500 mg daily for 4 weeks, 1000 mg daily for 4 weeks, and 1500 mg daily for 4 weeks

1

500 mg daily for 4 weeks, 1000 mg daily for 4 weeks, and 1500 mg daily for 4 weeks

2
L-NMMADRUG
1

Eligibility Criteria

Age18 Years - 65 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Males or females 18 to 65 years of age.
  • Diagnosis of sickle cell disease (electrophoretic or HPLC documentation of hemoglobin S only phenotype is required).
  • Hemoglobin greater than 5.5 grams per deciliter
  • Absolute reticulocyte count greater than 95,000 microliters if hemoglobin is less than 9.0 grams per deciliter.
  • An apoA-1 level lower than 99 milligrams per deciliter (median value among sickle cell subjects), or HDL-C level below 39 milligrams per deciliter (median value amongst our sickle cell cohort).

You may not qualify if:

  • Acute pain crisis requiring intravenous analgesics within the last week.
  • Current pregnancy or lactation.
  • Hemoglobin SC disease, or hemoglobin A greater than 20%
  • Conditions that may independently affect endothelial function:
  • Diabetes mellitus
  • Cigarette smoking within one month
  • Uncontrolled hypertension
  • Serum creatinine greater than 2.0 milligram per deciliter
  • Uric acid level greater than 8 or history of gout
  • History of GI bleeding within the past 6 months
  • Active peptic ulcer disease
  • Hemoglobin less than or equal to 5.5 grams per deciliter; however, subjects may return for evaluation at a later date.
  • No aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) for 1 week prior to forearm blood flow assessment and no caffeine the day of each forearm blood flow study. Subjects on opiates or acetaminophen will not be excluded.
  • Subjects taking sildenafil, vardenafil, tadalafil, L-arginine, fibrates (e.g., clofibrate, gemfibrozil, or fenofribrate) or inhaled nitric oxide within the last week will be excluded from the study.
  • Subjects taking any statin drug (e.g., fluvastatin, lovastatin, pravastatin, simvastatin, rosuvastatin) within the last four weeks will be excluded from the study.
  • +4 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (2)

Howard University Hospital

Washington D.C., District of Columbia, 20060, United States

Location

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

  • Barter PJ, Nicholls S, Rye KA, Anantharamaiah GM, Navab M, Fogelman AM. Antiinflammatory properties of HDL. Circ Res. 2004 Oct 15;95(8):764-72. doi: 10.1161/01.RES.0000146094.59640.13.

    PMID: 15486323BACKGROUND
  • Kwiterovich PO Jr. The antiatherogenic role of high-density lipoprotein cholesterol. Am J Cardiol. 1998 Nov 5;82(9A):13Q-21Q. doi: 10.1016/s0002-9149(98)00808-x.

    PMID: 9819099BACKGROUND
  • Viswambharan H, Ming XF, Zhu S, Hubsch A, Lerch P, Vergeres G, Rusconi S, Yang Z. Reconstituted high-density lipoprotein inhibits thrombin-induced endothelial tissue factor expression through inhibition of RhoA and stimulation of phosphatidylinositol 3-kinase but not Akt/endothelial nitric oxide synthase. Circ Res. 2004 Apr 16;94(7):918-25. doi: 10.1161/01.RES.0000124302.20396.B7. Epub 2004 Feb 26.

    PMID: 14988229BACKGROUND

MeSH Terms

Conditions

Anemia, Sickle Cell

Interventions

omega-N-MethylarginineAcetylcholine

Condition Hierarchy (Ancestors)

Anemia, Hemolytic, CongenitalAnemia, HemolyticAnemiaHematologic DiseasesHemic and Lymphatic DiseasesHemoglobinopathiesGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and Abnormalities

Intervention Hierarchy (Ancestors)

ArginineAmino Acids, BasicAmino AcidsAmino Acids, Peptides, and ProteinsAmino Acids, DiaminoAmino Acids, EssentialBiogenic AminesAminesOrganic Chemicals

Study Officials

  • John F Tisdale, M.D.

    National Heart, Lung, and Blood Institute (NHLBI)

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
NIH
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 27, 2007

First Posted

July 30, 2007

Study Start

July 24, 2007

Primary Completion

December 31, 2010

Study Completion

December 24, 2015

Last Updated

September 10, 2020

Record last verified: 2015-12-24

Locations