NEW YORK – A new program at the US Food and Drug Administration holds promise for streamlining development of gene and gene-editing therapies, according to experts.
The FDA last week released a draft guidance outlining how, within a Platform Technology Designation Program, it is hoping to accelerate the development and regulatory review of investigational medicines by allowing sponsors to submit as part of biologics license applications and new drug applications certain evidence they generated on previously approved products that incorporate the same components. This flexibility, the agency believes, would mean that sponsors could more easily leverage the same vectors or gene editors across multiple products and reduce repeated testing of the same technology.
The biopharmaceutical industry, so far, is reacting positively to the draft guidance, with some suggesting a platform approach could be exactly what's needed to spur development of gene-editing therapies.
A designation for platform technologies would not be an incremental step but a giant leap forward, said Fyodor Urnov, a professor in the molecular and cell biology department at the University of California, Berkeley, and director of technology and translation at the Innovative Genomics Institute (IGI), a collaboration between UC Berkeley and UC San Francisco. "CRISPR is the poster child for what the FDA is talking about," he said. "This platform designation is exactly what we need to stand upon to get us to multiple approvals."
The first CRISPR-based medicine, Vertex Pharmaceuticals and CRISPR Therapeutics' Casgevy (exagamglogene autotemcel), was approved last year, representing a major scientific milestone. However, industry players and regulators alike have questioned the feasibility of having gene-editing therapies make their way through the FDA's review process, given the time and cost of R&D work. If companies could retool their existing gene-editing technologies for different genetic targets without having to bring the same type of evidence for common therapeutic elements to regulators each time, they could advance more genetic medicines faster.
The American Society of Gene & Cell Therapy said it is pleased that the FDA has issued a draft guidance on platform technology designation, although its staff is still reviewing the document. "Platform technologies are critical to realizing the full potential of gene- and cell-based therapies," ASGCT CEO David Barrett said. "Potential designations [could] streamline gene and cell therapy development by allowing a single technology, such as a nucleic acid sequence or a vector, to be utilized across multiple products."
The draft guidance is a "great start" to developing a process for platform technologies, agreed Devyn Smith, CEO of Arbor Biotechnologies, a company developing gene-editing therapies. "We are very encouraged by the efforts of the FDA to find ways to allow biotechs leveraging well-understood reproducible technologies to more efficiently provide access to patients for potentially one-and-done therapies," Smith said. "We know this will continue to evolve as the FDA and the industry become more comfortable with the safety and efficacy profiles of gene-editing therapeutics."
The guidance is the first step in implementing a Congressional mandate included in the PREVENT Pandemics Act, which added language to the Federal Food, Drug, and Cosmetic Act for establishing a program to designate platform technologies. It was enacted as part of the 2023 Consolidated Appropriations Act.
In the draft guidance, the FDA defines a platform as a "well-understood and reproducible technology," for example, a set nucleic acid sequence, molecular structure, mechanism of action, delivery method, vector, or a combination of any such technologies that's part of a drug or facilitates the development of a drug.
A therapeutic component may be eligible for platform technology designation if it meets three main criteria: It must be part of an approved drug; evidence must suggest it can be used in other drugs without an adverse effect on quality, manufacturing, or safety; and evidence must suggest that using the platform has a "reasonable likelihood" of producing significant efficiencies.
FDA officials have previously highlighted gene-editing as an area that could benefit from a platform approach to drug development. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, specifically highlighted CRISPR as a promising platform technology at ASGCT's annual meeting in Baltimore last month.
Much of the time, a company's CRISPR-based therapeutic candidates may have very similar components and only switch out nucleotides in a guide RNA. "This is early on, but we have to be thinking now," Marks said at a fireside chat at the conference. "If [for] every base-pair change we're going to have people come back to the agency … there are a lot of nucleotides out there that can go wrong in the genome. I don't think we can have 3 billion visits to the FDA a year. We'll have to figure this out."
The FDA proposed in its draft guidance that drugmakers can request platform technology designation by submitting information showing that the therapeutic component meets the agency's definition of a platform and is part of an already approved product. The sponsor should also list all products in development or commercialized that use the platform technology and provide justification for its use across multiple drugs, among other evidence.
"The information above should be described with sufficient detail to support an evaluation of the risks associated with leveraging information about the platform technology," the FDA wrote.
The FDA's recommendations in draft and final guidance documents aren't legally binding on drugmakers but represent the agency's current thinking on how sponsors can best meet regulatory expectations. The agency said it will review requests for platform technology designations and issue its decisions within 90 days. The FDA in the draft guidance recommended drugmakers request platform technology designations during the investigational new drug (IND) phase of drug development, so the agency has sufficient review time.
Therapeutic elements that could be eligible for the Platform Technology Designation Program, according to the FDA's draft guidance, may include those that use a chemically defined targeting component in conjunction with a synthetic siRNA and lipid nanoparticle platforms for gene therapies, mRNA vaccines, or components that encapsulate different short, single-stranded or double-stranded oligonucleotides, for example.
Marks during the ASGCT conference also indicated that creating a path to streamline the review of platform technologies could benefit the development of rare disease therapeutics, which has been an ongoing focus for the FDA.
Aside from the challenges of developing an effective treatment for a rare disease, companies must also weigh the massive R&D investment needed to develop these drugs that would eventually be sold to very small patient populations. Some of the costs of developing rare disease drugs could be alleviated by being able to leverage the same CRISPR technology, for example, and not having to reproduce nonclinical tests each time the company puts forth a similar drug candidate with a different targeted mutation.
A platform designation could make the development process for drugmakers trying to develop cures for rare diseases more efficient and cost-effective, suggested Julie Allickson, director of Mayo Clinic's Center for Regenerative Biotherapeutics. "Their strategy has the potential to reduce preclinical development time, for example by leveraging the same vector," she said of the FDA's draft guidance.
That's also the goal at the Danaher-IGI Beacon for CRISPR Cures, a center newly launched by life sciences firm Danaher, the IGI, and UC Los Angeles. Researchers at the center, led by Urnov and CRISPR pioneer and IGI Founder Jennifer Doudna, are designing CRISPR treatments for two rare immune disorders, in the hopes of establishing new efficiencies that could inform future treatment programs, which could potentially reprogram the CRISPR component to target other genetic mutations.
The opportunity for a platform designation "is literally the thing we need," said Urnov, whose salary at the center is supported by Danaher.
While he's bullish on the Platform Technology Designation Program, Urnov said he would like to see the FDA broaden its eligibility criteria in the final guidance by considering platform technologies even if they haven't been incorporated into an approved product yet. He worries the requirement that a technology must already be used in an approved product could hamper the designation's usefulness when therapies are being developed for extremely rare conditions that don't already have marketed products.
This designation program could provide crucial opportunities for conversations with the FDA, said Jason Cole, CEO of SalioGen Therapeutics, which has genetic medicines in preclinical studies for Stargardt disease and cystic fibrosis. However, he said he would like to see the FDA extend these benefits early in the development cycle.
"This is an encouraging step forward for patients, and something many of us [developing] advanced therapies have advocated for years," he said. "A program like this will create a critical framework to enable companies like SalioGen to collaborate with the FDA to efficiently define and leverage modular technology elements, which is particularly important in rare diseases like inherited retinal diseases."
In addition to being able to leverage previously submitted evidence, such as certain manufacturing and nonclinical safety data, drugmakers with the designation may also be able to engage with the FDA early to discuss use of the platform technology, the FDA said in the draft guidance. The FDA specified, though, that only the drugmaker awarded the designation may leverage the platform in future applications, unless another company has struck an appropriate business arrangement.
"The potential benefits for the sponsor granted a platform technology are highly valuable in accelerating the development of the subsequent product," said Abla Creasey, VP of therapeutics development at the California Institute for Regenerative Medicine, which funds research into regenerative medicine treatments.
John Finn, CSO of genetic medicines developer Tome Biosciences, said this program will be positive for the gene therapy and gene-editing field. He expects that some of Tome's technologies will be eligible for the Platform Technology Designation Program, such as its delivery systems or enzymes.
"This program is very much in line with the guidance that Peter Marks has been giving over the past year that they [at the FDA] understand that gene therapy and gene editing doesn't fit into the classical drug development pathway and that they want to work with the field to improve the efficiency of the approval process," Finn said.
When the FDA finalizes this guidance, Finn hopes to see more details on what changes are allowed in a construct for it to still meet the agency's definition of a platform.
The FDA is seeking feedback on the draft guidance and will collect comments until July 29.