The first generation of CRISPR medicines proved that programmable editing can treat human disease. It also exposed how far the technology remains from becoming a broad healthcare platform. The approved therapy for sickle cell disease requires cells to be removed from a patient, edited in a specialised facility, checked, returned after intensive conditioning and managed by an expert clinical team. That is a scientific triumph wrapped in a costly delivery system.
Feng Zhang’s latest work goes after the constraints inside that wrapper. In 2025, his laboratory at the Broad Institute and MIT described TIGR-Tas, an ancient family of RNA-guided systems found largely in viruses that infect bacteria. More than 20,000 Tas proteins were identified. Some could be directed to cut DNA in human cells, they did not depend on the short adjacent DNA motifs that constrain Cas9, and they were, on average, about one quarter of Cas9’s size. In a separate project, Zhang’s team helped engineer Cas9 and Cas12 enzymes to reduce immune recognition while preserving editing activity in mice.
Neither result is a medicine. Both address bottlenecks that now determine the economics of genetic medicine: how much editing machinery can fit inside a delivery vehicle, which tissues can be reached, whether the immune system will reject repeat exposure, and how safely a treatment can move beyond a few elite hospitals. Zhang made his reputation by converting bacterial defence systems into practical tools. His 2026 leadership test is whether the expanding catalogue can be disciplined into products rather than remaining an abundance of elegant possibilities.
Size is a commercial variable
In gene editing, molecular size affects far more than laboratory convenience. Viral vectors have limited cargo capacity. Lipid nanoparticles and other non-viral approaches face their own packaging, stability and tissue-targeting constraints. A smaller editor leaves room for regulatory elements, guide components or multiple functions. It may enable a single vehicle where a larger system requires split delivery, reducing complexity and the chance that only part of the treatment reaches a cell.
TIGR-Tas therefore carries a plausible economic advantage before anyone assigns it a clinical indication. Simpler packaging can improve manufacturing yield, reduce dose requirements and widen the set of tissues that can be targeted. The lack of a Cas9-style PAM requirement could expand addressable mutations. A dual-guide mechanism that recognises both DNA strands may offer another route to specificity. Yet these are platform attributes, not clinical evidence. Efficiency in human cells, off-target activity, durability, immunogenicity and manufacturability must be established for each engineered system and delivery context.
The distinction matters because biotechnology has repeatedly priced discovery platforms as if optionality were the same as an approved pipeline. It is not. Each additional editor generates patents, licensing choices, assays and optimisation work. It can also fragment capital. A company may spend years improving a novel nuclease only to find that an older system with a mature manufacturing process remains better for the chosen disease. Zhang’s strength—mining natural diversity for new biological machinery—creates a corresponding management challenge: deciding which tools deserve the expensive transition into therapeutics.
The market now rewards that selectivity. After the exuberant financing cycle of the early 2020s, gene-therapy companies have faced tighter capital, clinical setbacks and pressure to demonstrate a credible route to reimbursement. Investors are less impressed by a platform that can theoretically address dozens of diseases if none can be developed with a manageable trial, production process and price. Compactness matters when it removes cost or risk from a defined product. It has little value as an adjective.
The immune system is part of the balance sheet
CRISPR proteins come from microbes, which means the human immune system may recognise them. Pre-existing immunity can reduce efficacy or raise safety concerns; an immune response may also complicate repeat dosing. Zhang’s 2025 collaboration with Cyrus Biotechnology used computational design to mask immune-triggering regions on Cas9 and Cas12. In mice, the redesigned enzymes retained similar editing efficiency while producing lower immune responses than standard versions.
If that performance translates, the commercial implications extend through a programme’s life cycle. Developers could reach patients previously excluded because of immunity, lower the risk attached to systemic administration and preserve the possibility of another dose. Repeat dosing is especially important outside one-time ex vivo treatments. Liver, muscle, lung and central-nervous-system indications may require delivery strategies whose effectiveness varies between patients. A platform that permits adjustment has more value than one that uses its therapeutic option only once.
But immune evasion creates its own regulatory burden. Modifying a well-characterised enzyme changes the evidence package. A reduced response in mice does not predict every feature of human immunity, and the edits designed to hide a protein must not alter its activity in unexpected ways. Regulators will expect sensitive assays, long follow-up and manufacturing consistency. The safer-looking molecule may initially be more expensive to validate because there is less historical experience behind it.
This is the central trade-off in Zhang’s programme. New biological systems can solve weaknesses in the incumbent technology, but Cas9 now benefits from a deep ecosystem: published data, trained staff, suppliers, regulatory familiarity and clinical precedent. A superior editor must beat not just Cas9’s molecular performance but its accumulated institutional capital.
From open tools to controlled products
Zhang has long made research reagents broadly available, helping CRISPR spread quickly across academic biology. That openness created scientific network effects. Commercial medicines operate under different rules. Companies need defensible intellectual property to finance toxicology, manufacturing and trials; universities want licensing returns; patients and health systems need competition to restrain price. The leadership challenge is to preserve research diffusion while creating enough exclusivity for development.
The record of CRISPR shows both sides. The technology catalysed a generation of listed and private biotechnology companies and enabled the first Cas9-based therapy, which used a design Zhang developed in 2015. It also produced long-running disputes over patent rights and a complex licensing landscape. The next set of systems offers a chance to structure access more deliberately. Non-exclusive research use, indication-specific commercial rights and access provisions for lower-income markets can coexist, although only if negotiated before a successful asset becomes scarce.
Capital allocation must also move beyond the editor itself. Delivery technologies, analytical methods, cell manufacturing and clinical infrastructure may capture as much value as the nuclease. A technically modest improvement in liver targeting could create more patient benefit than a dramatic new editor that cannot reach the relevant tissue. Zhang’s current roles across MIT, the McGovern Institute, HHMI and the Broad give him influence over what the academic ecosystem considers prestigious. Directing talent towards delivery is therefore a leadership decision, not merely a laboratory preference.
Asia needs a different deployment model
Asia illustrates why delivery and cost are inseparable. The region carries a large burden of inherited blood disorders, including beta-thalassaemia across South and Southeast Asia, alongside rare diseases that are individually small but collectively substantial. It also contains world-class research hospitals in Japan, South Korea, Singapore, China and India. Yet specialist capacity and reimbursement vary sharply within and between countries. A therapy designed around lengthy hospital stays, bespoke logistics and multimillion-dollar economics will reach only a fraction of eligible patients.
Smaller in vivo editors could change that equation if they permit treatment through a standardised infusion or injection. They could reduce reliance on exporting cells, central manufacturing and conditioning regimens. Local production of vectors or nanoparticles could shorten supply chains. Regional trial networks could generate data across ancestries that remain underrepresented in global genomic databases. None of these outcomes follows automatically from a compact protein. They require technology transfer, regulatory alignment, quality systems and a commercial model that recognises very different national ability to pay.
Asian biopharmaceutical groups also face a strategic choice. Licensing a finished Western programme is faster but leaves much of the platform value elsewhere. Building delivery capability, disease registries and genomic cohorts is slower but creates leverage across multiple therapies. For governments, investments in newborn screening and molecular diagnosis may produce an earlier return than subsidising a handful of advanced treatments. Gene editing has little population-level value when patients are not identified or cannot reach a qualified centre.
Geopolitics adds friction. Genome technologies sit within concerns about data security, dual use, research collaboration and supply-chain dependence. Zhang was born in China and built his career in the United States, an example of the cross-border talent flows that made modern biotechnology possible. Policies intended to protect sensitive technology can also narrow the exchange of basic knowledge and researchers on which discovery depends. Institutions must distinguish legitimate security controls from broad barriers that reduce scientific capacity on both sides.
The discipline after discovery
Zhang’s 2025 discoveries widen the design space. TIGR-Tas offers compact, modular, RNA-guided activity without the targeting constraint familiar from Cas9. Immune-masked enzymes suggest that an existing tool can be redesigned around the body’s response. His laboratory has also continued to search beyond CRISPR for systems capable of editing RNA, inserting larger DNA sequences and performing other programmable functions. The volume of invention is exceptional.
The next value inflection will come from subtraction. Which editor is sufficiently efficient to stop optimising? Which indication has biology clear enough to justify delivery investment? Which manufacturing process can be reproduced at commercial scale? Which safety concern should kill a programme early? These decisions lack the elegance of discovering a new molecular system, but they determine whether capital produces a therapy.
For Zhang, the most important measure by 2026 is no longer how many tools biology contains. It is how many constraints a chosen tool removes at once. A compact editor that still requires an expensive, fragile delivery chain will remain a laboratory achievement. An immune-evasive system that cannot be manufactured consistently will not improve access. His new generation will matter when it turns genome editing from a bespoke intervention into an operational platform—one that hospitals across Asia can use, regulators can assess and health systems can afford.
