Bidridistrogene xeboparvovec

The FDA has spotlighted a key component of Sarepta Therapeutics' experimental gene therapy for a form of muscular dystrophy, granting it a so-called platform technology designation. The status could help Sarepta fast-track development of future treatments using the same viral delivery system.The recognition went to Sarepta's viral vector – called rAAVrh74 – that is used in its gene therapy candidate SRP-9003, currently in late-stage testing for limb-girdle muscular dystrophy type 2E/R4 (LGMD2E/R4). "This is one of the first programmes to receive platform technology designation and an important recognition by FDA of the reproducibility and adaptability of this technology across multiple therapeutic programmes," said Louise Rodino-Klapac, the company's chief scientific officer.Pre-existing antibodies to adeno-associated virus (AAV) vectors can limit effectiveness of gene therapies and pose safety risks through inflammatory responses.The rAAVrh74 vector, originally derived from rhesus monkeys, may be able to sidestep some of those problems. A 2023 paper found that most Duchenne muscular dystrophy (DMD) patients in the study, about 86%, didn't have pre-existing antibodies against it. The authors suggested that this could make rAAVrh74 a better fit not only for DMD, but also for other neuromuscular diseases.With the platform designation in hand, Sarepta can now leverage previous data to speed up testing and approval for new treatments that use rAAVrh74, potentially cutting development timelines and regulatory review periods across its muscular dystrophy pipeline."The designation underscores and reinforces the consistency of the data we have seen with this AAVrh74 in multiple clinical programmes," Rodino-Klapac added.SRP-9003, also known as bidridistrogene xeboparvovec, is designed to deliver a full-length beta-sarcoglycan transgene and uses the MHCK7 promoter. It is currently being evaluated in the Phase III EMERGENE trial, with results expected by mid-2025 and a potential FDA submission in the second half of the year.

Dive Brief:The Food and Drug Administration has awarded Sarepta Therapeutics a new kind of fast pass that could help speed the reviews of certain gene therapy applications it brings to the regulator in the future.The so-called platform technology designation issued to Sarepta is meant to streamline the development and evaluation process for gene therapies using a specific delivery tool, a viral vector dubbed rAAVrh74. That component is part of multiple Sarepta programs, among them the already approved Duchenne muscular dystrophy gene therapy Elevidys.According to Sarepta, the designation is one of the first given to a drug program since the initiative was launched by the FDA. It enables Sarepta to use evidence previously gathered from studies involving the vector in future applications, though differences in how some of its newer gene therapies are manufactured may limit its usefulness.Dive Insight:The platform technology designation was conceived in 2023 and rolled out by the FDA the following year. The idea is to incentivize companies to use one drugmaking platform for multiple programs, which would enable the development and review process to move more quickly once an initial approval is granted.For genetic medicines, this concept could be particularly helpful. Many gene therapies and gene editing treatments are tailored to small subsets of patients with rare diseases. In some cases, their developers might be able to use the same underlying technology with one new component to treat an additional group of patients, or even a similar, but different disease. Currently, doing so typically involves the same lengthy and expensive drug development journey, making it a tough investment proposition.The platform technology designation could address that issue. To qualify, developers need to earn approval of a drug incorporating a technology, and generate evidence it can be used to speed forward other medicines without compromising quality or safety. Once they have the designation, they should benefit from efficiencies in drug development, manufacturing, and review processes, according to draft guidance issued last year.Sarepta uses the rAAVrh74 vector in Elevidys, a product already approved by the FDA. Its also incorporated in a limb-girdle muscular dystrophy treatment called SRP-9003 that could be submitted to regulators later this year, as well as at least two other programs for the muscle disease.The award could accelerate the development of Sareptas follow-on gene therapy programs and lower early R&D costs, wrote William Blair analyst Sami Corwin, in a Wednesday note to investors. It could also quell investor concerns about the safety of Elevidys following the death of a patient who received the therapy, she said, as some have speculated Sarepta could have its approval rescinded.Corwin did add, however, that its unclear how widely Sarepta may be able to use the designation, as management has suggested Elevidys and SRP-9003 are produced differently than SRP-9004 and SRP-9005, the two other limb-girdle gene therapies it has in development. '