Navigation Links
New gene therapy proves promising as hemophilia treatment
Date:12/11/2013

CHAPEL HILL, N.C. Researchers at the UNC School of Medicine and the Medical College of Wisconsin found that a new kind of gene therapy led to a dramatic decline in bleeding events in dogs with naturally occurring hemophilia A, a serious and costly bleeding condition that affects about 50,000 people in the United States and millions more around the world.

Before the gene treatment, the animals experienced about five serious bleeding events a year. After receiving the novel gene therapy, though, they experienced substantially fewer bleeding events over three years, as reported in the journal Nature Communications.

"The promise and the hope for gene therapy is that people with hemophilia would be given a single therapeutic injection and then would express the protein they are missing for an extended period of time, ideally for years or even their entire lifetimes," said Tim Nichols, director of the Francis Owen Blood Research Laboratory at UNC and co-author of the paper. The hope is that after successful gene therapy, people with hemophilia would experience far fewer bleeding events because their blood would clot better.

People with hemophilia A lack the coagulation factor VIII in their blood plasma the liquid in which red, white, and platelet cells are suspended.

"Bleeding events in hemophilia are severe, and without prompt factor VIII replacement, the disease can be crippling or fatal," said Nichols, a professor of medicine and pathology. "The random and spontaneous nature of the bleeding is a major challenge for people with hemophilia and their families."

In underdeveloped countries, people with hemophilia and many undiagnosed people typically die from bleeding in their late teens or early 20s. In developed countries, patients usually live fairly normal lives, as long as they receive preventive injections of recombinant protein therapy a few times a week. The disease requires life-long management that is not without health risks. The annual cost of medications alone is about $200,000 a year.

However, about 35 percent of people with hemophilia A develop an antibody response that blocks the factor VIII therapy. They require continuous infusions of various protein factors and they face a higher mortality rate. Also, the cost of treatment can easily rise to $2 million or more a year per patient.

Nichols and David Wilcox from the Medical College of Wisconsin figured out a potential way around the antibody response in dogs with naturally occurring hemophilia A.

Using a plasmapheresis machine and a blood-enrichment technique, the research team isolated specific platelet precursor cells from three dogs that have hemophilia A. The team then engineered those platelet precursor cells to incorporate a gene therapy vector that expresses factor VIII. The researchers put those engineered platelet precursors back into the dogs. As the cells proliferated and produced new platelets, more and more were found to express factor VIII.

Then, nature took over. Platelets naturally discharge their contents at sites of vascular injury and bleeding. In this experiment, the contents included factor VIII.

In the 2 1/2 years since the dogs received the gene therapy, researchers found that factor VIII was still being expressed in platelets that were coursing throughout the vascular systems of all three dogs. All three experienced much less bleeding. In the dog that expressed the most factor VIII in platelets, the bleeding was limited to just one serious event each year over the course of three years. And such bleeding events were easily treatable with current standard therapies.

"This has been very successful," Nichols said. "And now we want to explore the possibility of moving it into human clinical trials for people with hemophilia A, similar to what Paul Monahan and Jude Samulski at UNC are currently doing for people with hemophilia B, which is a deficiency of factor IX."

If approved, the platelet-targeted therapy would likely be restricted to patients who develop the antibody that stifles factor VIII therapy through normal injections. But as the gene therapy is refined, it could become a viable option for people with blood disorders who don't have inhibitory antibodies.


'/>"/>

Contact: Mark Derewicz
mark.derewicz@unch.unc.edu
919-923-0959
University of North Carolina Health Care
Source:Eurekalert  

Related biology news :

1. How can we improve the efficacy of antipsychotics in the era of personalized pharmacotherapy?
2. T cell immunotherapy: Promising results in children and adults with leukemia
3. International gene therapy trial for bubble boy disease shows promising early results
4. Penn Medicine team reports on study of first 59 leukemia patients who received cell therapy
5. Top 12 Pioneer Awards for seminal work in gene and cell therapy selected by blue ribbon panel
6. Hormone therapy could enhance the therapeutic effect of head and facial bone grafts
7. BUSM researchers study epigenetic mechanisms of tumor metastasis for improved cancer therapy
8. No evidence to support stem cell therapy for pediatric optic nerve hypoplasia
9. Largest therapy trial worldwide: Psychotherapy treats anorexia effectively
10. Biological therapy with cediranib improves survival in women with recurrent ovarian cancer
11. Trial combining anti-cancer drug and radiotherapy may lead to treatment for brain tumor
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New gene therapy proves promising as hemophilia treatment
(Date:6/9/2016)... June 9, 2016 Paris ... Teleste,s video security solution to ensure the safety of people ... during the major tournament Teleste, an international ... and services, announced today that its video security solution will ... to back up public safety across the country. The system ...
(Date:6/2/2016)... , June 2, 2016 ... Manned Platforms, Unmanned Systems, Physical Infrastructure, Support & Other ... provider visiongain offers comprehensive analysis of the ... this market will generate revenues of $17.98 billion in ... acquired DVTEL Inc, a leader in software and hardware ...
(Date:5/12/2016)... -- WearablesResearch.com , a brand of Troubadour Research ... the Q1 wave of its quarterly wearables survey. A ... to a program where they would receive discounts for ... "We were surprised to see that so ... , CEO of Troubadour Research, "primarily because there are ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... LOUISVILLE, Ky. , June 23, 2016 /PRNewswire/ ... from two Phase 1 clinical trials of its ... double-blind, placebo-controlled, single and multiple ascending dose studies ... and pharmacodynamics (PD) of subcutaneous injection in healthy ... APL-2 subcutaneously (SC) either as a single dose ...
(Date:6/23/2016)... On Wednesday, June 22, 2016, the NASDAQ Composite ... Jones Industrial Average edged 0.27% lower to finish at 17,780.83; ... has initiated coverage on the following equities: Infinity Pharmaceuticals Inc. ... NKTR ), Aralez Pharmaceuticals Inc. (NASDAQ: ARLZ ), ... more about these stocks by accessing their free trade alerts ...
(Date:6/23/2016)... ... 23, 2016 , ... Velocity Products, a division of Morris ... optimized exclusively for Okuma CNC machining centers at The International Manufacturing Technology Show, ... several companies with expertise in toolholding, cutting tools, machining dynamics and distribution, Velocity ...
(Date:6/22/2016)... June 22, 2016 Cell Applications, Inc. ... them to produce up to one billion human ... within one week. These high-quality, consistent stem cells ... cells and spend more time doing meaningful, relevant ... proprietary, high-volume manufacturing process that produces affordable, reliable ...
Breaking Biology Technology: