Adicet Bio Gets FDA Nod for IND Amendment to Study ADI-001 in Myopathy and Stiff Person Syndrome

Adicet Bio, Inc., a leading biotechnology firm specialized in developing allogeneic gamma delta T cell therapies, has received approval from the U.S. Food and Drug Administration (FDA) for an amendment to its Investigational New Drug (IND) application. This amendment allows the company to include idiopathic inflammatory myopathy (IIM) and stiff person syndrome (SPS) in its ongoing Phase 1 clinical trial for autoimmune diseases. Patient enrollment for these conditions is scheduled to begin in the first quarter of 2025. This is an expansion of their ADI-001 clinical development program, which now encompasses six distinct autoimmune diseases.

The FDA had previously agreed to amendments to Adicet Bio’s IND application, allowing the evaluation of ADI-001 for three additional indications, namely systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV), alongside lupus nephritis (LN). This marks a substantial step forward for Adicet Bio in its mission to address a broader spectrum of autoimmune conditions.

Chen Schor, President and Chief Executive Officer at Adicet Bio, expressed his optimism about the recent FDA approval. He highlighted the importance of this development in expanding the company’s research into autoimmune diseases and the potential benefits of their gamma delta T cell therapy candidates for patients who need new treatment options. Schor also pointed to recent clinical biomarker data that showed significant B-cell depletion and targeted tissue and organ trafficking, reinforcing the potential of ADI-001 as a top-tier treatment for autoimmune diseases. The company is set to begin patient enrollment for IIM and SPS in early 2025.

The Phase 1 clinical trial for ADI-001 in autoimmune diseases is structured into four distinct arms. One arm will enroll patients with LN and SLE, another will involve SSc patients, a third will include AAV patients, and the fourth will comprise patients with IIM and SPS. This fourth cohort will integrate various IIM subtypes such as dermatomyositis, anti-synthetase syndrome, immune-mediated necrotizing myopathy, polymyositis, and overlap myositis. Each enrolled patient will receive a single dose of ADI-001, with a 28-day dose-limiting toxicity assessment period. Response and safety evaluations will be conducted at Day 28 and at intervals up to 24 months. The main goals of the study are to assess the safety and tolerability of ADI-001, while secondary objectives focus on cellular kinetics, pharmacodynamics, changes in autoantibody levels, and disease activity scores in each specific condition.

Idiopathic inflammatory myopathy (IIM) encompasses a group of rare autoimmune diseases characterized by chronic muscle inflammation and progressive muscle weakness. These conditions primarily affect skeletal muscles but can also impact other organs such as the lungs, heart, and skin. The five main subtypes of IIM are dermatomyositis, anti-synthetase syndrome, immune-mediated necrotizing myopathy, polymyositis, and overlap myositis. IIM can significantly impair daily function and can be life-threatening, with no cure currently available.

Stiff person syndrome (SPS) is a rare neurological autoimmune disorder that causes severe muscle stiffness and spasms, mainly affecting the torso and limbs. This condition can severely impact mobility and everyday activities. Muscle spasms associated with SPS can be triggered by sudden stimuli, leading to a rigid, "statue-like" posture. Due to its rarity and symptom overlap with other disorders, SPS is often misdiagnosed. There is no cure available for SPS at present.

ADI-001 is an investigational therapy that uses allogeneic gamma delta chimeric antigen receptor (CAR) T cells targeting CD20 for the treatment of autoimmune diseases. It has been granted Fast Track Designation by the FDA for treating relapsed or refractory class III or IV lupus nephritis (LN). The ongoing Phase 1 study is also evaluating ADI-001 for SLE, SSc, AAV, IIM, and SPS. In preliminary trials, ADI-001 has demonstrated robust B-cell depletion and targeted tissue activity.

Adicet Bio, Inc. remains at the forefront of developing innovative gamma delta T cell therapies to combat both autoimmune diseases and cancer. The company continues to advance its pipeline of off-the-shelf gamma delta T cells engineered with CARs to provide long-lasting effects for patients.