The treatment at the center of the deal is imlifidase, which Sarepta Therapeutics has agreed a worldwide exclusive licensing deal for.
The company plans to use imlifidase as a pre-treatment before administering its own gene therapy to treat Duchenne muscular dystrophy (DMD) and Limb-girdle muscular dystrophy (LGMD).
In return, Hansa Biopharma, which owns imlifidase, will receive $10m (€8.8m) upfront and is eligible for further payments totaling up to $397.5m (€351.9m). In addition, Hansa will receive all sales for imlifidase and earn tiered royalties on any gene therapy sales received when patients are pre-treated with the drug.
The reason that Sarepta is prepared to pay such a price to get the treatment onboard is that it could enable its gene therapies to treat patients who would otherwise be ineligible.
Some potential patients have pre-existing antibodies to adeno-associated viruses (AAV), which would render any AAV delivery of gene therapy ineffective.
Hansa’s treatment targets the antibodies and inhibits an immune response in the patient, thereby clearing the way for the gene therapy to be administered successfully.
As a result, the drug could expand the treatment population for Sarepta’s gene therapies, should the combination prove effective in clinical trials.
Sarepta currently had a broad pipeline of gene therapies, including three for DMD and six for LGMD, all of which are at the preclinical or clinical stage.
At the end of last year, the company signed a $1bn deal with Roche for the development of one of those treatments for DMD, SRP-9001. As a result of this deal, Sarepta was able to invest in manufacturing capacity and infrastructure to support a potential wider commercialization effort.
In terms of the significance of the deal for Hansa, Søren Tulstrup, CEO of the company, stated that imlifidase could have ‘significant potential’ across the entire gene therapy space, where AAV technology has become the dominant form of delivery.