Scaling the promise of gene editing: Why progress still falls short of potential
Gene editing has progressed significantly over the past decade, evolving from an experimental technology that was associated with safety and efficacy limitations into a legitimate therapeutic avenue that has been tested across diseases and patient populations. Yet, while technical progress has been remarkable, real-world impact remains uneven. Investment, accessibility, and disease diversity continue to lag behind the field’s scientific potential.This blog explores how gene editing tools have evolved, what is limiting their translation into the clinic, and how researchers and regulators are trying to close the gap between innovation and impact.
Progress and potential
The approval of Casgevy in 2023 marked the first regulatory approval for a CRISPR–Cas9 therapy. Developed by Vertex Pharmaceuticals and CRISPR Therapeutics, it treats sickle cell disease and transfusion-dependent beta thalassemia by editing patient stem cells ex vivo. The therapy demonstrated that precise gene correction could produce durable clinical benefit.
In early 2025, the field achieved another milestone with the case of baby KJ Muldoon. A team led by Dr. Kiran Musunuru at the Children’s Hospital of Philadelphia developed and delivered a personalized in vivo CRISPR treatment within six months of diagnosis. The case was a proof of concept for on-demand genome editing in the clinic.
These examples illustrate the versatility of gene editing methods and the immense therapeutic benefit they can bring to patients with previously untreatable diseases.
Expanding the gene editing toolbox
Several gene editing tools are actively being developed to expand the toolbox beyond CRISPR. This new generation of technologies is addressing safety, precision, and delivery challenges that limited earlier programs.
Alternative gene editing techniques include base editing and prime editing. Unlike CRISPR editing, both base and prime editing offer the advantage of not requiring double-stranded DNA breaks (DSBs), which are associated with risks such as cellular apoptosis.
Base editing enables precise changes to individual bases. Beam Therapeutics has various in vivo base editing therapies in its pipeline, some of which are in phase I/II and exhibiting encouraging efficacy and safety profiles.
Prime editing expands editing capabilities further, allowing targeted insertions, deletions, and substitutions. Prime Medicine’s platform applies this approach to correct both coding and regulatory sequences. Their candidates are still in early development, with one target at the IND-enabling stage.
Tessera Therapeutics takes this a step further, using a technology for rewriting genes. This includes insertions, deletions, and replacements, which opens the possibility to address structural aberrations. This technology is still at the preclinical stage but has high potential and promise for a wide range of genetic diseases.
Together, these systems make editing more precise and versatile. They also demonstrate that gene editing research continues to advance, at a faster pace than translation into clinical programs.
Limited translation and slow clinical growth
Despite strong technical momentum, progress in translating these tools into approved therapies has been limited. Gene editing technologies have moved much slower than other types of precision therapies. For instance, whereas cell therapy and gene therapy biopharmas raised $1.826B and $580M, respectively, gene editing biopharmas have lagged behind with a total raise of $280M in 2024.
There are also concerns around the limited accessibility of these treatments. While various CRISPR-based therapies are already approved and in the market, they haven’t reached a large number of patients. In the UK, where Casgevy was approved in early 2025, the NHS reported that around 50 patients would receive the treatment per year. This represents meaningful progress for those eligible but also highlights how logistical, financial, and infrastructure barriers continue to limit broader access. In the US, roll-out has been similarly slow. As of June 2025, 29 patients had received Casgevy treatment, despite its approval two years earlier.
This slow uptake may help explain why gene-editing biopharmas have lagged behind other modalities in attracting investment. Compared with larger patient populations in oncology or rare disease gene therapy, the current addressable market for CRISPR-based treatments remains limited. The high cost, complex delivery process, and narrow disease focus make scalability difficult, which in turn dampens commercial enthusiasm. Until manufacturing and delivery models evolve to reach more patients efficiently, the field’s clinical and financial progress will likely remain uneven.
In line with this, at the European Society of Gene and Cell Therapy’s 2025 annual congress, Dr. Kiran Musunuru cautioned that KJ’s case, while groundbreaking, remains an exception. He noted that bespoke editing is still limited by cost, scalability, and unequal access to sequencing and variant data.
The field is therefore at a crossroads: it has proved what is scientifically possible but not yet what is clinically sustainable.
A narrow focus and the “hot dog” problem
Leaders in the field have also raised concerns about the narrow scope of development. Dr. Fyodor Urnov has described how biopharma investment patterns have led many companies to focus on the same small group of indications, despite an abundance of viable targets. He likened the situation to “being in a supermarket full of ingredients but everyone is making a hot dog.”
The result is a field dominated by redundant programs targeting sickle cell disease and alpha-1 antitrypsin deficiency (AATD), while hundreds of other rare or ultra-rare diseases remain unaddressed. Academic and nonprofit institutions are beginning to fill these gaps with smaller-scale, investigator-led trials, but the gap between market priorities and unmet medical need remains clear.
Moving forward: platform approval and practical progress
At ESGCT, Dr. Musunuru outlined potential paths to overcome these limitations. One solution is a platform or umbrella IND approach, where regulators approve shared components of a gene-editing system, such as delivery vectors or enzymes, that can then be adapted for multiple diseases without repeating the full review process each time. This can help streamline regulatory approval, lower development costs, and de-risk some aspects of the process.
He also emphasized that “perfect can’t be the enemy of good.” Incremental, iterative progress, he argued, is necessary to bring therapies to patients while continuing to refine precision and safety over time.
In a poignant editorial titled Give Cas a Chance, Dr. Urnov argued that while the technology is ready, the current model of advancing one bespoke program at a time is inefficient and unsustainable. He also proposed a shift toward platform development. Key priorities he outlined include:
- Reusing manufacturing and safety data when only the guide RNA changes, rather than repeating full preclinical studies.
- Adopting a stepwise expansion model, beginning with multiple guides for one gene, then several editors for that gene, and ultimately many genes within the same syndrome.
- Embedding regulatory flexibility, such as the FDA’s platform designation pathway, which allows data from a “parent” product to support future “offshoot” products.
- Leveraging academic and nonprofit consortia like the NIH Somatic Cell Genome Editing program to demonstrate these models in practice and share regulatory learnings openly.
Together, these steps can make gene editing scalable and sustainable, turning single breakthroughs into repeatable systems that can serve more patients. Early signs of this shift are already visible in interactions between regulatory bodies and biopharmas.
In parallel, more efficient manufacturing to lower costs, streamlined referral pathways, and clear reimbursement frameworks could help address financial barriers to uptake. The next stage of progress will depend less on scientific innovation and more on how well these systems can scale delivery for the patients who need it.