Unlike most other CRISPR/Cas-9 therapies that are ex vivo treatments in which cells are modified outside the body, this study was successful with an in vivo treatment
Use of CRISPR-Cas9 gene editing technology for therapeutic purposes can be a boon for clinical laboratories. Not only is this application a step forward in the march toward precision medicine, but it can give clinical labs the essential role of sequencing a patient’s DNA to help the referring physician identify how CRISPR-Cas9 can be used to edit the patient’s DNA to treat specific health conditions.
Most pathologists and medical lab managers know that CRISPR-Cas9 gene editing technology has been touted as one of the most significant advances in the development of therapies for inherited genetic diseases and other conditions. Now, a pair of biotech companies have announced a milestone for CRISPR-Cas9 with early clinical data involving a treatment delivered intravenously (in vivo).
As with other therapies, determining which patients are suitable candidates for specific treatments is key to the therapy’s success. Therefore, clinical laboratories will play a critical role in identifying those patients who would most likely benefit from a CRISPR-delivered therapy.
Such is the goal of precision medicine. As methods are refined that can correct unwelcome genetic mutations in a patient, the need to do genetic testing to identify and diagnose whether a patient has a specific gene mutation associated with a specific disease will increase.
Cleveland Clinic describes ATTR amyloidosis as a “protein misfolding disorder” involving transthyretin (TTR), a protein made in the liver. The disease leads to deposits of the protein in the heart, nerves, or other organs.
According to Intellia and Regeneron, NTLA-2001 is designed to inactivate the gene that produces the protein.
The interim clinical trial data indicated that one 0.3 mg per kilogram dose of the therapy reduced serum TTR by an average of 87% at day 28. A smaller dose of 0.1 mg per kilogram reduced TTR by an average of 52%. The researchers reported “few adverse events” in the six study patients, “and those that did occur were mild in grade.”
Current treatments, the companies stated, must be administered regularly and typically reduce TTR by about 80%.
“These are the first ever clinical data suggesting that we can precisely edit target cells within the body to treat genetic disease with a single intravenous infusion of CRISPR,” said Intellia President and CEO John Leonard, MD, in a press release. “The interim results support our belief that NTLA-2001 has the potential to halt and reverse the devastating complications of ATTR amyloidosis with a single dose.”
He added that “solving the challenge of targeted delivery of CRISPR-Cas9 to the liver, as we have with NTLA-2001, also unlocks the door to treating a wide array of other genetic diseases with our modular platform, and we intend to move quickly to advance and expand our pipeline.”
“It’s an important moment for the field,” MIT biomedical engineer Daniel Anderson, PhD (above), told Nature. Anderson is Professor, Chemical Engineering and Institute for Medical Engineering and Science at the Koch Institute for Integrative Cancer Research at MIT. “It’s a whole new era of medicine,” he added. Advances in the use of CRISPR-Cas9 for therapeutic purposes will create the need for clinical laboratories to sequence patients’ DNA to help physicians determine the best uses for a CRISPR-Cas9 treatment protocol. (Photo copyright: Massachusetts Institute of Technology.)
In Part 2 of the Phase 1 trial, Intellia plans to evaluate the new therapy at higher doses. After the trial is complete, “the company plans to move to pivotal studies for both polyneuropathy and cardiomyopathy manifestations of ATTR amyloidosis,” the press release states.
Previous clinical trials reported results for ex vivo treatments in which cells were removed from the body, modified with CRISPR-Cas9 techniques, and then reinfused. “But to be able to edit genes directly in the body would open the door to treating a wider range of diseases,” Nature reported.
How CRISPR-Cas9 Works
On its website, CRISPR Therapeutics, a company co-founded by Emmanuelle Charpentier, PhD, a director at the Max Planck Institute for Infection Biology in Berlin, and inventor of CRISPR-Cas9 gene editing, explained that the technology “edits genes by precisely cutting DNA and then letting natural DNA repair processes take over.” It can remove fragments of DNA responsible for causing diseases, as well as repairing damaged genes or inserting new ones.
The therapies have two components: Cas9, an enzyme that cuts the DNA, and Guide RNA (gRNA), which specifies where the DNA should be cut.
Charpentier and biochemist Jennifer Doudna, PhD, Nobel Laureate, Professor of Chemistry, Professor of Biochemistry and Molecular Biology, and Li Ka Shing Chancellor’s Professor in Biomedical and Health at the University of California Berkeley, received the 2020 Nobel Prize in Chemistry for their work on CRISPR-Cas9, STAT reported.
It is important to pathologists and medical laboratory managers to understand that multiple technologies are being advanced and improved at a remarkable pace. That includes the technologies of next-generation sequencing, use of gene-editing tools like CRISPR-Cas9, and advances in artificial intelligence, machine learning, and neural networks.
At some future point, it can be expected that these technologies will be combined and integrated in a way that allows clinical laboratories to make very early and accurate diagnoses of many health conditions.
In what could be a major boon to clinical laboratories and healthcare providers, researchers found that fears of rampant testing and ballooning spending due to results of whole-genome sequencing may be less of a concern than opponents claim
Clinical laboratory testing and personalized medicine (AKA, precision medicine) continue to reshape how the healthcare industry approaches treating disease. And, whole-genome sequencing (WGS) has shown promise in helping in vitro diagnostic (IVD) companies develop specific treatments for specific patients’ needs based on their existing conditions and physiology.
Nevertheless, WGS development and the ensuing controversy continues. This has motivated researchers at Brigham and Women’s Hospital (BWH) in Boston to engage in a study that compares the upfront costs of WGS to the downstream costs of healthcare, in an attempt to determine if and how whole-genome sequencing does actually impact the cost of care.
Are Doctors Acting Responsibly?
The MedSeq Project study, published in Genetics in Medicine, a journal of the American College of Medical Genetics and Genomics, involved 200 people—100 of them healthy, the other 100 diagnosed with cardiomyopathy. Roughly half of each group underwent whole-genome sequencing, while the other half used family history to guide treatments and procedures. The project then collected data on downstream care costs for the next six months for each group to compare how whole-genome sequencing might impact the final totals.
“Whole genome sequencing is coming of age, but there’s fear that with these advancements will come rocketing healthcare costs,” lead author Kurt Christensen, PhD, Instructor of Medicine in the Division of Genetics at BWH, stated in a press release.
“Our pilot study is the first to provide insights into the cost of integrating whole-genome sequencing into the everyday practice of medicine,” noted Kurt Christensen, PhD, lead author of the Brigham and Women’s Hospital study. “Our data [provides] reassurance that physicians seem to be responding responsibly and that we’re not seeing evidence of dramatically increased downstream spending.” (Photo copyright: ResearchGate.)
Clinical Laboratory Testing Largest Difference in Cost/Services Rendered
Within the healthy volunteer group, patients who based treatment decisions solely on their family medical history averaged $2,989 in medical costs over the next six months. Those who received WGS incurred $3,670 in costs.
Services also remained relatively consistent between both groups. The WGS group averaging 5.5 outpatient lab tests and 8.4 doctor visits across the period, while the family history group averaged 4.4 outpatient lab tests and 6.9 doctor visits.
Within the cardiology patient group, however, the dynamic flipped. WGS recipients averaged $8,109 in spending, while the family history group averaged $9,670. Study authors attribute this to the possibility of treatments while being hospitalized for concerns unrelated to the study.
When removing hospitalizations from the data set, the WGS group averaged $5,392, while the family history group averaged $4,962—a result similar to that of the healthy group.
Utilization of services was also similar. The WGS group averaged 7.8 doctor visits, while the family history group averaged 7.2 visits. However, the outpatient lab testing spread was wider than any other group in the study. WGS patients averaged 9.5 tests compared to the 6.5 of the family history group.
Unanswered Questions
In their report, the study’s authors acknowledged a range of questions still unanswered by their initial research.
First, the project took place at a facility in which physicians were educated in genetics, had contacts familiar with genetics, and had the support of a genome resource center. The level of experience with genetics may also have prevented additional spending by tempering responses to results.
Although the whole-genome sequencing that took place during the project uncovered genetic variants known to or likely to cause disease within the healthy population, this did not trigger the wave of testing or panic many opponents of genetic sequencing predicted.
Authors also acknowledge that a longer, larger study would offer more conclusive results. Researchers are planning for a longer 5-year study to verify their initial findings. However, study co-author Robert Green, MD, Director of the Genomes2People Research Program at BWH told STAT, “… downstream medical costs of sequencing may be far more modest than the common narrative suggests.”
Further Research Needed
The BWH researchers acknowledged that monetary cost is only one facet of the impact of genetic sequencing results. “Patient time costs were not assessed,” the study authors pointed out. “Nor were the effects of disclosure on participants’ family members, precluding a complete analysis from a societal perspective.”
Lastly, they noted that while the sample size sufficed to verify their results, diversity was lacking. In particular, they mentioned that the participant pool was “more educated and less ethnically diverse than the general population.”
The cost of genetic sequencing and similar technologies continue to drop as automation and innovation make the process more accessible to clinicians and healthcare providers. This could further impact longer studies of the overall cost of sequencing and other genetics-based tools.
For medical laboratories, these results offer proof to both payers and physicians on the value of services in relation to the overall cost of care—a critical concern, as margins continue to shrink and regulations focus on efficiency across a broad spectrum of healthcare-related service industries.
Stanford University School of Medicine researchers grew heart muscle cells and used them, along with CRISPR, to predict whether a patient would benefit or experience bad side effects to specific therapeutic drugs
What would it mean to pathology groups if they could grow heart cells that mimicked a cardiac patient’s own cells? What if clinical laboratories could determine in vitro, using grown cells, if specific patients would have positive or negative reactions to specific heart drugs before they were prescribed the drug? How would that impact the pathology and medical laboratory industries?
