FDA grants orphan drug status to Mustang Bio’s MB-108 for glioma

Mustang Bio has been granted orphan drug designation by the US Food and Drug Administration (FDA) for its oncolytic virus MB-108, which is designed to address malignant glioma. MB-108, derived from herpes simplex virus type 1, is a component of the treatment regimen MB-109. This regimen includes MB-101, a CAR-T-cell therapy aimed at the interleukin 13 receptor alpha 2, and MB-108, licensed from Nationwide Children’s Hospital.

The combination therapy of MB-109 has shown promise in preclinical studies, particularly for patients suffering from recurrent glioblastoma multiforme (GBM). It works by turning "cold" tumors, which are less responsive to immune treatments, into "hot" ones that are more susceptible to the immune system's attack. This conversion can potentially increase the effectiveness of the MB-101 CAR-T cell therapy.

Furthermore, data from clinical trials indicate that both MB-101 and MB-108 are well-tolerated by patients with recurrent GBM. Remarkably, two patients treated solely with MB-101 experienced complete responses. These patients had highly active immune systems, with a significant presence of cluster of differentiation 3+ T cells, leading to complete responses that lasted for over seven months and 31 months respectively. These results were the most notable among 53 participants in the City of Hope Phase I trial.

Current Phase I clinical trials for MB-101 are underway at City of Hope, while MB-108 trials are being conducted at the University of Alabama at Birmingham. Both trials are actively recruiting patients. The progression of the MB-109 program for recurrent GBM and high-grade astrocytomas is contingent on obtaining further funding or establishing strategic partnerships. Mustang Bio also plans to seek orphan drug designation for MB-101 from the FDA for treating malignant gliomas.

Manuel Litchman, the President and CEO of Mustang Bio, emphasized the significance of the orphan drug designation for MB-108. He highlighted that this designation could provide market exclusivity, enhancing the prospects for MB-108 when used in combination with MB-101 as a treatment for malignant glioma. This includes patients with recurrent glioblastoma and high-grade astrocytomas, conditions that historically have a median overall survival of just six months. Litchman underscored that their innovative therapeutic approach, which combines MB-108 oncolytic virus with MB-101 CAR-T-cell therapy, could represent the first industry-sponsored trial of its kind for treating malignant glioma.

As the field of cell and gene therapy continues to evolve, with new treatments emerging that have the potential to transform medical care and offer cures for various diseases, Mustang Bio's work on MB-109 reflects a significant step forward in the fight against aggressive brain tumors. The company's ongoing efforts and upcoming clinical trials will be crucial in determining the effectiveness and potential of these therapies to improve patient outcomes in the future.