Editas Medicine Seeks Partner for Ex Vivo Gene-Editing Amid In Vivo R&D Shift

Editas Medicine is making a strategic shift in its focus within the field of gene-editing therapies. The biotech company announced plans to partner or license out its clinical-stage ex vivo therapy for rare blood diseases, specifically targeting severe sickle cell disease and transfusion-dependent beta thalassemia. This decision allows Editas to concentrate its resources on in vivo research and development, which has recently shown promising preclinical proof-of-concept data.

The in vivo therapy, known as renizgamglogene autogedtemcel (reni-cel), is in late-stage clinical development for severe sickle cell disease and early-stage development for beta thalassemia. This shift comes in light of existing ex vivo gene-editing treatments for these conditions, such as Vertex Pharmaceuticals’ Casgevy, which received FDA approval for sickle cell disease and beta thalassemia last winter. Additionally, Bluebird Bio's Lygenia for sickle cell disease and Zynteglo for beta thalassemia have also gained FDA approvals.

Although reni-cel would be the third ex vivo gene-editing therapy to hit the market, Editas believes it could be the best in its class. The therapy involves editing a patient’s hematopoietic stem cells in a lab and then infusing them back into the patient to correct anemia and increase fetal hemoglobin levels. Dosing is ongoing in a pivotal study for sickle cell disease, with 28 adult patients treated so far, and adolescent patient dosing is scheduled. Data from these studies will be presented at the upcoming American Society of Hematology meeting in December. The beta thalassemia study is also on track to present clinical data by the year’s end.

Editas CEO Gilmore O’Neill emphasized the financial considerations of commercializing an ex vivo autologous therapy. By partnering reni-cel, Editas could significantly reduce its 2025 spending. This decision aligns with the company's progress in in vivo editing, which has shown encouraging results in preclinical models. Specifically, Editas reported a 29% editing level in hematopoietic stem cells after a single dose in mouse models, leading to the induction of fetal hemoglobin, indicated by the presence of HbF-expressing human red blood cells within a month. O'Neill noted that this level of editing is competitive compared to public data on in vivo therapies for sickle cell disease and beta thalassemia.

Leerink Partners analyst Mani Foroohar supported Editas's decision to seek an external partner for reni-cel, citing the high costs associated with commercializing autologous ex vivo therapies. He noted that the near-term focus for Editas shares would be the additional reni-cel data and how well the company can differentiate the therapy to attract business development interest.

To facilitate the partnering or out-licensing process, Editas has engaged investment bank Moelis & Company. Concurrently, the company has secured non-dilutive financing to support its in vivo gene-editing focus. Earlier this month, Editas sold future license fees and payments from Vertex Pharmaceuticals for Cas9 gene-editing technology to DRI Healthcare Trust, receiving $57 million upfront. Editas reported a cash position of approximately $320 million, including the DRI payment, which is expected to fund its operations into 2026.