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 Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland

nachricht Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>