See Inside
History explains why people with the malady, and their physicians, are cautious to believe that a cure is in sight
HEATHER VAN UXEM LEWIS
In 2011, a remarkable study in the New England Journal of Medicine detailed the successful treatment of six adults with haemophilia B, which is caused by a deficiency in the coagulation protein known as factor IX. All of the participants were able to eliminate or reduce the frequency of clotting-factor-replacement injectionsthe current standard treatment for the diseaseafter their livers began producing functional levels of factor IX. The experimental therapy came in the form of an adeno-associated virus (AAV) carrying a gene that encodes instructions for production of normal levels of human factor IX. Three trials of AAV-mediated gene transfer in patients with haemophilia B are ongoing, with high expectations.
After more than 20 years of research on gene transfer, it is a promising time for haemophilia therapies. It now seems likely that a single-dose treatment for haemophilia B using an AAV or another gene-transfer technique will be a viable option for many people in the next decade or two.
Yet haemophilia researchers are not inclined to speak enthusiastically of a cure. Part of that caution comes from recognition that there are still problems to solve. For example, some 40% of people with haemophilia B would find no refuge in an AAV treatment because they produce antibodies that attack and neutralize this virus.
And even if that problem were solved, the treatment would apply only to those with haemophilia B. The more common form of the condition, haemophilia A, stems from a deficit in another proteinfactor VIIIand the gene for that protein is a more difficult target. Regardless of the type of haemophilia, researchers remain hesitant about gene therapy owing to the unresolved ethical issues that arose decades ago.
The unfettered optimism that characterized the early years of gene-therapy research came to a screeching halt in 1999, when 18-year-old Jesse Gelsinger died in a phase I clinical trial at the University of Pennsylvania in Philadelphia. Gelsinger had undergone an experimental gene transfer for his otherwise treatable metabolic disorder. His death, along with a series of other harmful events in early gene-therapy trials for a variety of diseases, threatened the whole field.
Haemophilia specialists who were engaged in gene-transfer studies were more guarded than most of that era's self-proclaimed gene doctors. The source of their reserve goes beyond the cautious optimism that characterized such research after 1999; it is grounded instead in the long and troubled experience that the haemophilia community has had with technological fixes.
By the late 1970s, a therapeutic revolution had transformed haemophilia from an obscure hereditary malady into a manageable disease. But the glory of this achievement was tragically short-lived. The same clotting-factor-replacement therapies that delivered a degree of normality to the lives of people with haemophilia brought unexpected and fatal results: tens of thousands of people with haemophilia were diagnosed with transfusion-related HIV/AIDS in the 1980s and with hepatitis C virus (HCV) in the 1990s.
Read the original here:
Gene Therapys Hemophilia Promise Is Tempered by Memories of Past Tragedies
- Gene Therapy: Ethical Issues: Information from Answers.com [Last Updated On: February 6th, 2014] [Originally Added On: February 6th, 2014]
- Gene, immune therapy help cancer war [Last Updated On: April 10th, 2014] [Originally Added On: April 10th, 2014]
- Gene Therapy - Genetics Home Reference - Your guide to ... [Last Updated On: April 10th, 2014] [Originally Added On: April 10th, 2014]
- What is gene therapy? - Genetics Home Reference [Last Updated On: April 10th, 2014] [Originally Added On: April 10th, 2014]
- Gene therapy - Wikipedia, the free encyclopedia [Last Updated On: April 10th, 2014] [Originally Added On: April 10th, 2014]
- Gene Therapy PSA Dan Lesser Period 2 - Video [Last Updated On: April 15th, 2014] [Originally Added On: April 15th, 2014]
- Gene therapy basics - Video [Last Updated On: April 15th, 2014] [Originally Added On: April 15th, 2014]
- In vivo gene therapy - Video [Last Updated On: April 15th, 2014] [Originally Added On: April 15th, 2014]
- Ex vivo gene therapy - Video [Last Updated On: April 15th, 2014] [Originally Added On: April 15th, 2014]
- Broad Institute Gets Patent on Revolutionary Gene-Editing Method [Last Updated On: April 17th, 2014] [Originally Added On: April 17th, 2014]
- Gene Therapy - Video [Last Updated On: April 17th, 2014] [Originally Added On: April 17th, 2014]
- Mark Hamalainen: Gene Therapy - Video [Last Updated On: April 17th, 2014] [Originally Added On: April 17th, 2014]
- JFK - Gene Therapy for Brain Tumors - Video [Last Updated On: April 18th, 2014] [Originally Added On: April 18th, 2014]
- Fixing the Liver with New Gene Therapy (Brainstorm Ep178) - Video [Last Updated On: April 18th, 2014] [Originally Added On: April 18th, 2014]
- Gene Therapy | Buzzle.com [Last Updated On: April 22nd, 2014] [Originally Added On: April 22nd, 2014]
- Gene Therapy I - RCN Corporation [Last Updated On: April 22nd, 2014] [Originally Added On: April 22nd, 2014]
- Ricky Ashby Microbiology Podcast - Video [Last Updated On: April 22nd, 2014] [Originally Added On: April 22nd, 2014]
- Regrown nerves boost bionic ears [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Cochlear Implant Plus Gene Therapy Could Restore Hearing to the Deaf [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Scientists reverse memory loss in mice with Alzheimer's [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Bionic Ears Boosted by Gene Therapy and Regrown Nerves [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Study: Gene Therapy May Boost Cochlear Implants [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Gene therapy may boost hearing, study finds [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Pronounce Medical Words Gene Therapy - Video [Last Updated On: April 24th, 2014] [Originally Added On: April 24th, 2014]
- Gene therapy may boost power of cochlear implants, study says [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- Gene therapy shows promise to help people regrow auditory nerve cells [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- Cochlear Implant Also Uses Gene Therapy to Improve Hearing [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- Gene Therapy May Enhance Cochlear Implants, Animal Study Finds [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- Uniqure Gene Therapy Info. - Video [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- Jean Bennett on gene therapy as a treatment for blindness - Video [Last Updated On: April 25th, 2014] [Originally Added On: April 25th, 2014]
- mice-science-AFPrelax-250414.jpg [Last Updated On: April 26th, 2014] [Originally Added On: April 26th, 2014]
- Cochlear implant enhances patient experience through gene therapy [Last Updated On: April 28th, 2014] [Originally Added On: April 28th, 2014]
- Gene therapy may help hearing [Last Updated On: April 28th, 2014] [Originally Added On: April 28th, 2014]
- Ethics of Gene therapy - Video [Last Updated On: April 30th, 2014] [Originally Added On: April 30th, 2014]
- Novel Financing For Gene Therapy Company [Last Updated On: May 1st, 2014] [Originally Added On: May 1st, 2014]
- Gene Therapy To Enhance Hearing - ABC Austrlia News - 2014 - - Video [Last Updated On: May 1st, 2014] [Originally Added On: May 1st, 2014]
- Biotechnology - GMO's & Gene Therapy - Video [Last Updated On: May 1st, 2014] [Originally Added On: May 1st, 2014]
- Cochlear Implant Gets an Upgrade with Gene Therapy - Video [Last Updated On: May 4th, 2014] [Originally Added On: May 4th, 2014]
- Gene therapy for haemophilia - Professor Amit Nathwani - Video [Last Updated On: May 4th, 2014] [Originally Added On: May 4th, 2014]
- Retrovirus in Gene Therapy - Video [Last Updated On: May 4th, 2014] [Originally Added On: May 4th, 2014]
- Regeneron, Avalanche To Develop Novel Gene Therapy Products In Ophthalmology [Last Updated On: May 5th, 2014] [Originally Added On: May 5th, 2014]
- Gene Therapy Used to Preserve Sight in Patients [Last Updated On: May 5th, 2014] [Originally Added On: May 5th, 2014]
- SCID gene therapy class - Video [Last Updated On: May 6th, 2014] [Originally Added On: May 6th, 2014]
- Gene Therapy using SMaRT - Video [Last Updated On: May 6th, 2014] [Originally Added On: May 6th, 2014]
- gene therapy video - Video [Last Updated On: May 9th, 2014] [Originally Added On: May 9th, 2014]
- Chronic Granulomatous Disease (CGD) - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Gene Therapy (Breast Cancer) - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Suicide gene therapy - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Employment of gene therapy in depression (psychiatric disorder) - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Gene therapy for blindness (2012) - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- AGRC1020 Video Presentation Gene Therapy restores colour vision in monkeys - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- gene therapy~3 - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Gene Delivery System (In-vivo and Ex-vivo) HD - Video [Last Updated On: May 12th, 2014] [Originally Added On: May 12th, 2014]
- Spark Therapeutics to open headquarters in West Philadelphia [Last Updated On: May 14th, 2014] [Originally Added On: May 14th, 2014]
- Gene Therapy - Nature [Last Updated On: May 14th, 2014] [Originally Added On: May 14th, 2014]
- Gene therapy for RTT syndrome benefits and drawbacks - Video [Last Updated On: May 16th, 2014] [Originally Added On: May 16th, 2014]
- Gene Therapy (Using Biolistic gene gun for gene delivery) - Video [Last Updated On: May 16th, 2014] [Originally Added On: May 16th, 2014]
- Germline Gene Therapy - Video [Last Updated On: May 16th, 2014] [Originally Added On: May 16th, 2014]
- Gene Therapy Biology Project for Swavely - Video [Last Updated On: May 16th, 2014] [Originally Added On: May 16th, 2014]
- Gene therapy extends survival in an animal model of spinal muscular atrophy [Last Updated On: May 22nd, 2014] [Originally Added On: May 22nd, 2014]
- Novel RNAi therapy silences mutated Huntington's disease gene and reduces symptoms [Last Updated On: May 22nd, 2014] [Originally Added On: May 22nd, 2014]
- Global Gene Therapy Market: Analysis, Size, Share, Growth, Trends and Forecast 2013 - 2019 [Last Updated On: May 22nd, 2014] [Originally Added On: May 22nd, 2014]
- Gene therapy hits blood cancers hard [Last Updated On: May 22nd, 2014] [Originally Added On: May 22nd, 2014]
- Spark Therapeutics late-stage gene therapy for inherited blindness takes a $73M step forward [Last Updated On: May 31st, 2014] [Originally Added On: May 31st, 2014]
- Genome Editing to Reverse Bubble Boy Syndrome [Last Updated On: May 31st, 2014] [Originally Added On: May 31st, 2014]
- Genetic Researching: Gene Therapy - Video [Last Updated On: May 31st, 2014] [Originally Added On: May 31st, 2014]
- BEYOND THE BUBBLE: 10 Years of Gene Therapy - Video [Last Updated On: May 31st, 2014] [Originally Added On: May 31st, 2014]
- Gene Therapy Combined with IMRT Found to Reduce the Rate of Positive Prostate Biopsy After Treatment for Intermediate ... [Last Updated On: June 4th, 2014] [Originally Added On: June 4th, 2014]
- Gene therapy combined with IMRT found to reduce recurrence for select prostate cancer patients [Last Updated On: June 4th, 2014] [Originally Added On: June 4th, 2014]
- Gene therapy combined with IMRT reduces rate of positive prostate biopsy after treatment for intermediate-risk ... [Last Updated On: June 4th, 2014] [Originally Added On: June 4th, 2014]
- Bluebird, Agios: Preview of Next Week's Important Pipeline Updates [Last Updated On: June 12th, 2014] [Originally Added On: June 12th, 2014]
- Attack of the B - Team EP8 - Drowning for Science! - Video [Last Updated On: June 12th, 2014] [Originally Added On: June 12th, 2014]
- 3rd International Conference and Exhibition on Cell & Gene Therapy - Video [Last Updated On: June 14th, 2014] [Originally Added On: June 14th, 2014]
- Blood Disorder Patients Respond Strongly to Bluebird Bio Gene Therapy [Last Updated On: June 15th, 2014] [Originally Added On: June 15th, 2014]
- Gene Therapy Partnering Terms and Agreements - Video [Last Updated On: June 15th, 2014] [Originally Added On: June 15th, 2014]
- Gene Therapy - GMAT Free - GFSC120 - Video [Last Updated On: June 18th, 2014] [Originally Added On: June 18th, 2014]
- New Gene Therapy Rapidly Helps Patients With Rare Blood Disorder - Video [Last Updated On: June 18th, 2014] [Originally Added On: June 18th, 2014]
- Isis Could Get a $2 Billion Gain From Heart Attack Trials [Last Updated On: June 22nd, 2014] [Originally Added On: June 22nd, 2014]
- Gene Therapy for Beta Thalassemia - Video [Last Updated On: June 22nd, 2014] [Originally Added On: June 22nd, 2014]
- A level. R.7. Cystic fibrosis and gene therapy (Ms Cooper) - Video [Last Updated On: June 24th, 2014] [Originally Added On: June 24th, 2014]