Sarepta Therapeutics, Inc. announced an agreement with Hansa Biopharma, the leader in immunomodulatory enzyme technology for rare Immunoglobulin G (IgG) mediated diseases, for imlifidase. Under the terms of the agreement, Sarepta obtains an exclusive, worldwide license to develop and promote imlifidase as a pre-treatment to enable Sarepta gene therapy administration in Duchenne muscular dystrophy (DMD) and Limb-girdle muscular dystrophy (LGMD), for patients who may otherwise not be eligible for treatment.
Sarepta’s investigational gene therapies use an adeno-associated virus (AAV) and patients with Duchenne and LGMD who have pre-existing IgG antibodies are not currently eligible for treatment with any AAV-based gene therapies. Imlifidase is an antibody-cleaving enzyme that specifically targets IgG and inhibits an IgG-mediated immune response. Imlifidase has a rapid onset of action, cleaving IgG-antibodies and inhibiting their reactivity within hours after administration, thus clearing the AAV-IgG antibodies that would typically preclude dosing or re-dosing with AAV.
“As we expand our leadership position in genetic medicine and build out our gene therapy engine, one of Sarepta’s central ambitions is to find scientific solutions that bring our potentially life-saving therapies to the greatest number of the rare disease patients we serve,” said Doug Ingram, president and chief executive officer, Sarepta Therapeutics. “One of the current limitations of gene therapy is the inability to treat patients who have pre-existing neutralizing antibodies to the AAV vector. While our AAVrh74 vector has been associated with a low screen out rate for neutralizing antibodies, even that low rate is inconsistent with our mission. In pre-clinical and clinical models, Hansa’s technology has shown the ability to clear the IgG antibodies that prevent dosing AAV-based gene therapies. If successful, this could offer the potential of extending our gene therapy treatments to DMD and LGMD patients who would otherwise have been denied access due to pre-existing antibodies.”
“We see significant potential for our enzyme technology in the gene therapy space overall, and we are excited to partner with Sarepta, a leading player in the field, to use the unique features of imlifidase to potentially enable gene therapy treatment in patients who today aren’t eligible for these breakthrough therapies due to pre-existing neutralizing antibodies in two conditions with a very high unmet medical need,” said Søren Tulstrup, president and chief executive officer, Hansa Biopharma.
Under the terms of the agreement, Hansa will receive an upfront payment of $10 million and is eligible for additional development, regulatory and sales milestone payments potentially totaling up to $397.5 million. Hansa will book all sales of imlifidase and will earn tiered royalties up to the mid-teens on any incremental gene therapy sales that arise from treating antibody-positive patients enabled through imlifidase pre-treatment.