After years of ethical debates and breakthroughs in the lab, CRISPR has finally made its way to clinical trials. Researchers are now looking at whether the DNA-editing tool, as well as more conventional gene therapies, can effectively treat a wide array of heritable disorders and even cancers.
Theres been a convergence of the science getting better, the manufacturing getting much better, and money being available for these kinds of studies, says Cynthia Dunbar, a senior investigator at the National Heart, Lung, and Blood Institute. Its truly come of age.
CRISPR formally known as CRISPR-Cas9 has been touted as an improvement over conventional gene therapy because of its potential precision. CRISPR (clustered regularly interspaced short palindromic repeats) is a genetic code that, contained in a strand of RNA and paired with the enzyme Cas9, acts like molecular scissors that can target and snip out specific genes. Add a template for a healthy gene, and CRISPRs cut can allow the cell to replace a defective gene with a healthy one.
In April, scientists at the University of Pennsylvania announced they had begun using CRISPR for cancer treatments. The first two patients one with multiple myeloma, the other with sarcoma had cells from their immune systems removed. Researchers used CRISPR to genetically edit the cells in the lab, and then returned them back into their bodies.
On the other side of the country, Mark Walters, a blood and bone marrow transplant specialist at the University of California, San Francisco, Benioff Childrens Hospital in Oakland, is gearing up for trials that will use CRISPR to repair the defective gene that causes sickle cell disease. With CRISPR, once youve made that type of correction, [that cell] is 100 percent healthy, says Walters.
Another team is tackling the same disease using a type of hemoglobin, a protein in red blood cells, thats normally made only in fetuses and newborn babies. Researchers found that some adults continue to produce these proteins throughout their lives, and when those adults also have sickle cell disease, their symptoms are mild. So the international team used CRISPR to disable the gene that interferes with production of this hemoglobin, resuming its production and protecting the adult patients against sickle cell disease.
Several other CRISPR studies are in the works to treat a range of inherited disorders, including hemophilia and SCID-X1 (also known as X-linked severe combined immunodeficiency, the so-called bubble boy disease in which babies are born without a functioning immune system).
At St. Jude Childrens Research Hospital, a gene therapy trial cured Gael Jesus Pino Alva (pictured with his mother, Giannina) of SCID-X1, the bubble boy disease. (Credit: St. Jude Children's Research Hospital/Peter Barta)
The past year also saw success in a handful of experiments on conventional gene therapy. Instead of using CRISPR to repair disease-causing genes, these treatments use hollowed-out viruses to ferry healthy versions of genes into cells. Millions of these altered cells are released into the bloodstream or bone marrow in hopes that enough will land in the right places. But because scientists cant predict where the circulating genes may end up, this shotgun approach has had unintended, sometimes fatal, consequences including, in an earlier study, inadvertently activating leukemia-causing genes in patients treated for SCID-X1.
But in 2019, researchers learned that using a different type of virus one related to HIV to transport the genes may prevent these side effects. In an April study, researchers at St. Jude Childrens Research Hospital in Memphis, Tennessee, and UCSF Benioff Childrens Hospital in Oakland collected bone marrow from eight newborns with SCID-X1. They loaded corrective genes into the disabled HIV-related virus, which carried them into the patients bone marrow stem cells. The infants also received low doses of busulfan, a chemotherapy that gave the doctored stem cells room to grow. So far, we havent seen anything worrisome, says Ewelina Mamcarz, a pediatric oncologist at St. Jude who led the research team. The study recently added its 12th patient.
Gene therapy does have its momentum [back], says Mamcarz, reflecting on the fields setback after the earlier studys leukemia side effects. Theres so much that still needs to be done, and so many questions, she says. [But] this is how medicine evolves. We always want to be better than we were a week ago.
In the future, the hope is that gene therapy technologies will move beyond mending simple genetic mistakes and be used to combat big killers like diabetes or heart disease. [Those diseases are] more challenging, but a lot of them would benefit from knocking out a bad gene, says Dunbar.
For now, though, researchers are optimistic about the progress thats already been made. All of this has been very encouraging, says Dunbar. [And] for sickle cell in the U.S. and hemophilia in the developed world, these diseases may soon be solved.
[This story originally appeared in print as "Gene Therapy Gets Clinical."]
Read the original here:
Gene Therapies Make it to Clinical Trials - Discover Magazine
- About the Gene Therapy Review - November 8th, 2009 [November 8th, 2009]
- Contribute an Article - November 8th, 2009 [November 8th, 2009]
- EBSCO Publishing Deal - November 8th, 2009 [November 8th, 2009]
- Advertising Opportunities - November 8th, 2009 [November 8th, 2009]
- Instructions for Authors - November 8th, 2009 [November 8th, 2009]
- Isis Collaboration With Ortho-McNeil Inc for Metabolic Diseases - November 8th, 2009 [November 8th, 2009]
- Dystrophin Gene Transfer safe in Duchenne muscular dystrophy - November 8th, 2009 [November 8th, 2009]
- Researchers Identify Gene for Rare Form of Spinal Muscular Atrophy - November 8th, 2009 [November 8th, 2009]
- Fatal brain cancer tamed by New gene therapy - November 8th, 2009 [November 8th, 2009]
- Gene therapy effective in fighting obesity in mice - November 8th, 2009 [November 8th, 2009]
- Genzyme gene therapy for people with peripheral artery disease failed in a clinical trial to help them regain some mobility - November 8th, 2009 [November 8th, 2009]
- Gene Therapy May Stall Inherited Emphysema - December 31st, 2009 [December 31st, 2009]
- Gene Therapy and Stem Cells Save Limb - December 31st, 2009 [December 31st, 2009]
- TNVitamins.com – $10 Off Of $50 order - May 7th, 2011 [May 7th, 2011]
- 15% Off Any PetAlive Order - May 7th, 2011 [May 7th, 2011]
- At PetAlive – $10 off order of $50 or more - May 7th, 2011 [May 7th, 2011]
- Native Remedies coupon – 5% Off Any Order - May 7th, 2011 [May 7th, 2011]
- Native Remedies – Save $5 coupon - May 7th, 2011 [May 7th, 2011]
- Welcome to the Gene Therapy Review - May 15th, 2011 [May 15th, 2011]
- Editorial Board - May 15th, 2011 [May 15th, 2011]
- Gene Therapy Job Board - May 15th, 2011 [May 15th, 2011]
- Corporate Membership - May 22nd, 2011 [May 22nd, 2011]
- Native Remedies coupon – 25% Off Any Order - May 29th, 2011 [May 29th, 2011]
- What is Gene Therapy? - June 19th, 2011 [June 19th, 2011]
- Research and Markets: Recent Advances in Cancer Research and Therapy - Increased Research on one of the Major Causes ... - April 25th, 2012 [April 25th, 2012]
- Gene Therapy part 2 - Video - April 30th, 2012 [April 30th, 2012]
- Gene therapy reverses Parkinson's symptoms: study - Video - April 30th, 2012 [April 30th, 2012]
- CBS This Morning - Gene therapy reverses Parkinson's symptoms: study - Video - April 30th, 2012 [April 30th, 2012]
- Engineering adenoviruses for gene therapy - Video - April 30th, 2012 [April 30th, 2012]
- What is Gene Therapy (The General Explains) - Video - April 30th, 2012 [April 30th, 2012]
- What is Gene Therapy - Animation - Video - April 30th, 2012 [April 30th, 2012]
- Microbiology Gene Therapy - Video - April 30th, 2012 [April 30th, 2012]
- Gene Therapy in Detail - Video - April 30th, 2012 [April 30th, 2012]
- Breakthrough in Haemophilia treatment - Video - April 30th, 2012 [April 30th, 2012]
- Virology Seminar - Gene Therapy - April 30th, 2012 [April 30th, 2012]
- Gene Therapy Video - Video - April 30th, 2012 [April 30th, 2012]
- Study: Gene Therapy for HIV Safe, But Effectiveness Still Unclear - May 4th, 2012 [May 4th, 2012]
- Gene Therapy Safe in Decade-Long HIV Study That May Widen Use - May 4th, 2012 [May 4th, 2012]
- Gene therapy for HIV safe, but effectiveness still unclear - May 4th, 2012 [May 4th, 2012]
- A Step Forward For Gene Therapy To Treat HIV - May 4th, 2012 [May 4th, 2012]
- A Media Event on Clinical Developments in Gene and Cell Therapy - May 4th, 2012 [May 4th, 2012]
- Families of SMA Awards New Funding to Advance a CNS Delivered Gene Therapy for Spinal Muscular Atrophy - May 4th, 2012 [May 4th, 2012]
- AIDS gene therapy safe -- is it a "cure"? - May 4th, 2012 [May 4th, 2012]
- Generational Achievements in Gene and Cell Therapy Honored at ASGCT 15th Annual Meeting - May 5th, 2012 [May 5th, 2012]
- Lewis speaks on gene therapy at Lexington Community Education event - May 7th, 2012 [May 7th, 2012]
- Penn researchers report a gene-therapy success - May 10th, 2012 [May 10th, 2012]
- Gene therapy for hearing loss: Potential and limitations - May 13th, 2012 [May 13th, 2012]
- Gene therapy extends mouse lifespan by 24 pc - May 16th, 2012 [May 16th, 2012]
- Gene therapy dramatically extends mouse lifespan - May 16th, 2012 [May 16th, 2012]
- Gene therapy may extend life: Study - May 16th, 2012 [May 16th, 2012]
- First gene therapy successful against aging-associated decline: Mouse lifespan extended up to 24% with a single ... - May 16th, 2012 [May 16th, 2012]
- Gene Therapy Extends Mouse Lifespan - May 16th, 2012 [May 16th, 2012]
- Gene Therapy for Brain Disease - May 17th, 2012 [May 17th, 2012]
- Children with rare, incurable brain disease improve after gene therapy - May 17th, 2012 [May 17th, 2012]
- FIRST Anti-Aging Gene Therapy (Brainstorm Ep72) - Video - May 23rd, 2012 [May 23rd, 2012]
- Gene therapy can correct forms of severe combined immunodeficiency - May 25th, 2012 [May 25th, 2012]
- RetroSense Therapeutics Completes pre-IND Meeting for RST-001 - May 25th, 2012 [May 25th, 2012]
- Gene therapy can correct forms of severe combined immunodeficiency, study suggests - May 26th, 2012 [May 26th, 2012]
- Alliance for Cancer Gene Therapy celebrates 10 years - May 29th, 2012 [May 29th, 2012]
- Research on gene therapy by Prasad Eye - June 1st, 2012 [June 1st, 2012]
- Baxter Announces Collaboration with Chatham Therapeutics for Factor IX Hemophilia B Gene Therapy Treatment - June 5th, 2012 [June 5th, 2012]
- Transgenomic Launches Breakthrough Blood-Based Cancer Gene Testing Technology at 2012 ASCO Annual Meeting - June 5th, 2012 [June 5th, 2012]
- Baxter Inks Deal with Chatham - June 6th, 2012 [June 6th, 2012]
- PIK3CA Gene Patent for Predicting Response to Targeted Therapy Issued – Exclusively Licensed to Transgenomic - June 11th, 2012 [June 11th, 2012]
- SalutarisMD Announces Positive Case Report of a New Investigational Wet AMD Therapy at ARVO - June 15th, 2012 [June 15th, 2012]
- Research and Markets: Gene Therapy - Global Strategic Business Report - 2012 - June 15th, 2012 [June 15th, 2012]
- New York Law Firm’s MesotheliomaHelp.net Site Publishes Interview with Gene Therapy Author - June 17th, 2012 [June 17th, 2012]
- uniQure Extends Collaboration with Protein Sciences Corporation on Use of its expresSF+® Cell Line for Gene Therapy - June 19th, 2012 [June 19th, 2012]
- Anti-cocaine vaccine described in Human Gene Therapy Journal - June 19th, 2012 [June 19th, 2012]
- bluebird bio Receives U.S. and European Orphan Drug Designation for Novel Gene Therapy to Treat Adrenoleukodystrophy - June 19th, 2012 [June 19th, 2012]
- Close to a cure: Greater Hartford takes on rare Jewish genetic disease - June 19th, 2012 [June 19th, 2012]
- Gene Therapy Helps Treat Children with Rare Brain Disorder - June 20th, 2012 [June 20th, 2012]
- Gold nanoparticles capable of 'unzipping' DNA - June 21st, 2012 [June 21st, 2012]
- ‘Gene-silencing’ drug can halt and reverse deadly brain disorder - June 21st, 2012 [June 21st, 2012]
- uniQure Collaborates with UCSF on GDNF Gene Therapy in Parkinson's Disease - June 22nd, 2012 [June 22nd, 2012]
- Gene-silencing method offers possible therapy for Huntington's disease - June 22nd, 2012 [June 22nd, 2012]
- Gene mutations cause massive brain asymmetry - June 24th, 2012 [June 24th, 2012]
- Research and Markets: Translational Regenerative Medicine - Oncology, CNS and Cardiovascular-Rich Pipeline Features ... - June 25th, 2012 [June 25th, 2012]
- Stress Blocks Gene That Guards Brain Against Depression - June 26th, 2012 [June 26th, 2012]
- Targeted gene therapy enhances treatment for Pompe disease - June 26th, 2012 [June 26th, 2012]