September 01, 2022

Immusoft Announces FDA Clearance of IND Application for ISP-001 for MPS I, the First Engineered B Cell Therapy to Enter into Clinical Trials

  • Immusoft makes history with the first engineered B cell investigational therapy cleared for human trials
  • Immusoft seeks to improve the treatment of MPS I, a rare childhood disease, through the use of its Immune System Programming (ISP™) approach that utilizes B cells as re-dosable biofactories for therapeutic protein delivery
  • The company has received FDA Orphan Drug Designation and Rare Pediatric Disease Designation for ISP-001 in MPS I (Mucopolysaccharidosis type I) and will launch its Phase 1 study this year

SEATTLE–(BUSINESS WIRE)–Immusoft, a clinical-stage cell therapy company dedicated to improving the lives of patients with rare diseases, today announced that the U.S. Food and Drug Administration (FDA) has cleared the Investigational New Drug Application (IND) for ISP-001 in the treatment of MPS I. The open IND enables Immusoft to initiate a Phase 1 clinical study.

This milestone is both significant for Immusoft and historic in the field of cell and gene therapies, as ISP-001 will be the first engineered B cell therapy to enter into human clinical trials. Immusoft has pioneered the engineering of B cells to create biofactories for in vivo therapeutic protein delivery, leading the field with over 60 issued and pending patents. The company’s novel B cell platform was designed to circumvent immunogenicity associated with virus-delivered gene therapy and chemotherapy preconditioning associated with stem cell-mediated gene therapy, while enabling durable therapeutic delivery and the possibility to re-dose.

MPS I is a rare, childhood genetic disease that affects the body’s ability to produce an essential enzyme, resulting in progressive damage to tissues and organs. Children with MPS I require frequent infusions, which impacts quality of life and is expensive. Immusoft’s ISP™ approach is designed to enable reprogramming of the patient’s B cells for constant production of therapeutic proteins, mitigating the need for frequent infusions with the possibility to improve patient outcomes. ISP-001 represents the first product candidate developed using the company’s proprietary techniques.

“There is a clear need for additional therapies for MPS I, as current interventions are not curative and significant disease related morbidity still exists,” said Paul Orchard, M.D. Professor, Division of Pediatric Bone Marrow Transplantation, University of Minnesota Medical Center. “A non-viral gene delivery method such as ISP-001 holds great promise with the potential to provide definitive therapy.” Dr. Orchard serves as the principal investigator on the ISP-001 Phase 1 clinical trial.

“The ISP platform is a first-in-class technology and a pioneering new approach to treat human disease. It has been rewarding to collaborate with patients, the FDA, investigators, and the Immusoft organization to achieve this important milestone and to launch the first-in-human clinical study,” said Robert Sikorski, MD PhD, Chief Medical Officer, Immusoft.

With this IND clearance, Immusoft is now in a strong position to advance its broad pipeline of therapies toward the clinic, including near-term rare disease programs and expanding into areas including cardiovascular, autoimmune and CNS. The company has partnered with the California Institute for Regenerative Medicine (CIRM) in the development of its program for MPS II, a rare childhood genetic disease. Immusoft has also entered into a research collaboration and license option agreement with Takeda Pharmaceutical Company Limited aimed at delivering protein therapeutics across the blood-brain barrier to treat neurometabolic disorders.

“We are pleased with the FDA’s clearance of our IND application for our lead candidate ISP-001 in MPS I. This is a huge achievement for the Company and a historic moment in the field of cell and gene therapies,” said Sean Ainsworth, CEO and Chairman, Immusoft. “I look forward to working with our team and investigators to initiate our Phase I clinical trial later this year and to continue our commitment to the development of our engineered B cell platform for patients in need.”

About MPS I (Mucopolysaccharidosis type I)

MPS I (Mucopolysaccharidosis type I) is a rare, lethal childhood genetic disease that affects the body’s ability to produce IDUA (alpha-L-iduronidase), which is an essential enzyme that helps to break down long-chain sugars inside cells. When the sugar chains cannot be broken down and disposed of, they accumulate in the cells and cause progressive damage. This accumulation can happen in the tissues, including the brain. In its most severe form, children affected rarely live longer than ten years after diagnosis. Severe MPS I occurs in about 1 in 100,000 births and symptoms appear within a child’s first year of life. In what is referred to as attenuated MPS I, symptoms appear later in childhood. It occurs in about 1 in 500,000 births.

About Immusoft

Immusoft is a clinical stage cell therapy company focused on developing novel therapies for rare diseases using a sustained delivery of protein therapeutics from a patient’s own cells. The company has developed a technology platform called Immune System Programming (ISP™), which modifies a patient’s B cells and instructs the cells to produce gene-encoded medicines. The B cells that are reprogrammed using ISP become miniature drug factories that are expected to persist for many years. The company is based in Seattle, WA. For more information, visit

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