Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stroke Prevention Study in Children with Sickle Cell Anemia, Iron Overload Stopped Early

07.06.2010
Experimental Approach Seems no Better Than Standard Treatment

The National Heart, Lung, and Blood Institute (NHLBI) has stopped a clinical trial evaluating a new approach to reduce the risk of recurrent stroke in children with sickle cell anemia and iron overload because of evidence that the new treatment was unlikely to prove better than the existing treatment.

The 26-site trial, Stroke With Transfusions Changing to Hydroxyurea, or SWiTCH, studied 133 participants between the ages of 5 and 18 who had already experienced a stroke. All had been receiving the standard treatment of blood transfusions for at least 18 months and high levels of iron before entering the study. Without further preventive measures, these children were at high risk of another stroke as well as life-threatening conditions due to iron overload.

The study tested whether the drug hydroxyurea, known to prevent complications of sickle cell disease in adults, was as effective as transfusions, the standard therapy, in reducing the risk of recurrent strokes. Hydroxyurea is the only FDA-approved drug for treating sickle cell anemia.

The study also compared two approaches to remove excess iron, a consequence of regular blood transfusions. Participants who continued to receive transfusion therapy were given the standard oral iron-removal drug deferasirox, and participants who were switched to hydroxyurea underwent regular phlebotomy (blood removal) to eliminate excess iron that had accumulated from their earlier transfusions.

Phlebotomy did not reduce liver iron better than deferasirox therapy. Analysis of the available data indicated that continuing the trial was unlikely to show that phlebotomy would provide a greater benefit than deferasirox to control iron accumulation. Without the ability to provide benefits for the management of liver iron, the potential risks of continuing study treatments were no longer warranted.

“Protecting our participants is an important factor in determining whether to stop a trial,” said Susan B. Shurin, MD, acting director of the NHLBI, who is a board-certified hematologist and pediatrician. The NHLBI is part of the National Institutes of Health. “When an experimental treatment fails to meet its predetermined goals, it is best to return participants to standard treatment as soon as possible.”

By the time the trial was halted, approximately one-third of participants had completed the study, during which they were treated and monitored for 30 months. At enrollment, participants were randomly assigned to either the alternative or the standard treatment group. The study’s independent Data and Safety Monitoring Board (DSMB) reviewed interim results from the trial and recommended stopping the study. The NHLBI accepted the recommendation and stopped the study on May 6.

The DSMB noted that no strokes occurred in the 66 participants who received the standard therapy of blood transfusions and deferasirox. In contrast, seven strokes occurred in the group of 67 participants who received hydroxyurea with phlebotomy. Study participants and their families have been contacted, and they will discuss future care options with their health care providers.

NHLBI-supported research has shown that hydroxyurea helps prevent pain crises, a common complication of the disease, and some lung complications in adults. Preliminary studies have suggested that hydroxyurea might also help reduce the risk of stroke recurrence in children with sickle cell disease. Patients currently taking hydroxyurea should continue taking the treatment as prescribed and should talk to their primary care provider if they have any concerns, Shurin advised.

Regular blood transfusions greatly reduce the number of strokes in at-risk children with sickle cell disease. Because repeated transfusions cause side effects such as buildup of excess iron in the body, researchers hope to find more effective and safer ways to reduce stroke risk in young patients. Iron overload can damage organs and lead to cirrhosis (a liver condition), poor growth and development, and heart rhythm disturbances.

“These kinds of studies are so important to finding new treatments and confirming that current standards of care are the best available options,” Shurin explained. “The field of medicine would not advance without the help of those willing to participate in clinical research. We are grateful to these young patients and their parents for helping advance treatments of sickle cell disease. Their contributions will help us find other approaches to preventing complications of sickle cell disease.”

About 10 percent of children with sickle cell disease suffer a stroke. Having experienced one, they are at high risk of having another unless they receive preventive treatment.

Sickle cell disease affects more than 70,000 Americans. It is seen mostly in persons of African descent, but also in individuals of Middle Eastern, Mediterranean, Central and South American, and Asian Indian heritage. New therapies have helped patients live into middle age and older. Sickle cell disease involves an altered gene that produces abnormal hemoglobin, the protein that carries oxygen in the blood. Red blood cells with sickle hemoglobin become C-shaped, stiff, and sticky when they release the oxygen they carry.

The deformed cells impede blood flow, causing severe pain and organ damage.
The study was scheduled to run until 2012. Rho Inc. of Chapel Hill, N.C., served as the SWiTCH statistics and data management center. Researchers will analyze and publish the final data in the coming months. SWiTCH was conducted at the following locations:
University of Alabama at Birmingham Children’s National Medical Center, Washington, D.C.Nemours Children’s Clinic, Jacksonville, Fla. University of Miami, Fla. Nemours Children’s Clinic, Orlando, Fla. Children’s Healthcare of Atlanta at Scottish Rite Children’s Healthcare of Atlanta at Egleston Children’s Healthcare of Atlanta at GradyChildren’s Memorial Hospital, Chicago Boston Children’s Hospital Wayne State University, Detroit University of Mississippi Medical Center, Jackson The Children’s Mercy Hospital, Kansas City St. Joseph’s Children’s Hospital, Paterson, N.J. Montefiore Medical Center, New York CityState University of New York/Downstate Medical Center, New York CitySchneider Children’s Hospital, New Hyde Park, N.Y.Columbia University Medical Center, New York CityEast Carolina University, Greenville.Cincinnati Children’s Hospital The Children’s Hospital of Philadelphia Children’s Hospital of Pittsburg Medical University of South Carolina, CharlestonSt. Jude Children’s Research Hospital, Memphis, Tenn. University of Texas Southwestern Medical Center at Dallas Baylor College of Medicine, HoustonEast Virginia Medical School, Norfolk Medical College of Wisconsin, Milwaukee
Novartis US donated the deferasirox (EXJADE). Bristol-Myers Squibb and UPM Pharmaceuticals Inc. provided the hydroxyurea for the trial.
To speak with an NHLBI spokesperson about the SWiTCH trial (NCT00122980), please contact the NHLBI Communications Office at (301) 496-4236.
Part of the National Institutes of Health, the National Heart, Lung, and Blood Institute (NHLBI) plans, conducts, and supports research related to the causes, prevention, diagnosis, and treatment of heart, blood vessel, lung, and blood diseases; and sleep disorders. The Institute also administers national health education campaigns on women and heart disease, healthy weight for children, and other topics. NHLBI press releases and other materials are available online at www.nhlbi.nih.gov.
The National Institutes of Health (NIH) — The Nation's Medical Research Agency — includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
Resources:
Diseases and Conditions Index: Sickle Cell Disease: http://www.nhlbi.nih.gov/health/dci/Diseases/Sca/SCA_Treatments.html
NIH Consensus Development Conference Statement: Hydroxyurea Treatment for Sickle Cell Disease. http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=12656&nbr=6551

Press Release on Consensus Document http://public.nhlbi.nih.gov/newsroom/home/GetPressRelease.aspx?id=2552

NHLBI Communications Office | EurekAlert!
Further information:
http://www.nhlbi.nih.gov

More articles from Studies and Analyses:

nachricht Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT

nachricht Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>