Vertex Pharmaceuticals has reported groundbreaking results from its phase 1/2 trial of VX-880, an islet cell therapy for type 1 diabetes, showing that three patients were able to completely discontinue insulin therapy within a year of treatment. The data, presented at the American Diabetes Association (ADA) annual congress in Florida, suggests the therapy can restore the physiological function of insulin-producing pancreatic cells and normalize glucose control.
The study enrolled 17 participants with type 1 diabetes who had impaired hypoglycemia awareness, putting them at high risk for severe hypoglycemic events (SHEs) that can lead to serious complications including confusion, seizures, and even death. Of the 12 patients who received the full dose of VX-880 as a single infusion, all three who reached the 12-month follow-up milestone achieved the primary endpoint: elimination of SHEs, reduction of hemoglobin A1c to 7% or less, and complete insulin independence.
Rapid and Consistent Clinical Benefits
The results showed remarkably consistent benefits across the treatment group. All 12 full-dose recipients demonstrated evidence of islet cell engraftment and insulin production within three months of treatment. By the data cutoff, 11 of these 12 patients had either reduced or completely eliminated their insulin requirements.
"The full dose of VX-880, given as a single infusion, demonstrates consistent engraftment of islets with restoration of endogenous insulin secretion, elimination of severe hypoglycemia and significant improvement of glycemic control," said Dr. Michael R. Rickels, Professor in Diabetes and Metabolic Diseases at the University of Pennsylvania Perelman School of Medicine and medical director of the pancreatic islet cell transplant program.
Among the 10 participants who completed the six-month follow-up visit, seven had completely discontinued insulin therapy, while two others had reduced their daily insulin requirements by approximately 70%.
Dramatic Improvements in Glycemic Control
The therapy demonstrated substantial improvements in glycemic control. Time-in-range (blood glucose between 70-180 mg/dL) increased from a baseline average of 49.5% to 76.1% at 90 days and 88.3% at 180 days. For the four patients with complete one-year follow-up data, time-in-range reached an impressive 95.1%, approaching normal glucose regulation.
Carmen Bozic, Vertex's Chief Medical Officer, described the data as "remarkable" and part of "growing evidence for VX-880 as a potentially curative therapy for type 1 diabetes." Based on these promising results, regulators have approved expanding enrollment to approximately 37 patients, and Vertex is planning pivotal studies to support regulatory approval.
Current Limitations and Future Directions
The current version of VX-880 uses "naked" cells, requiring patients to take immunosuppressive medications to prevent rejection. All 14 study participants experienced adverse events related to immunosuppressive therapy, though researchers reported that no severe adverse events were attributed to VX-880 itself.
To address this limitation, Vertex is developing VX-264, an encapsulated version of the therapy designed to protect the cells from immune rejection without requiring immunosuppression. A phase 1/2 trial of VX-264 began last year.
Competitive Landscape in Type 1 Diabetes Cell Therapy
Vertex has made significant investments in its type 1 diabetes cell therapy platform, including the nearly $1 billion acquisition of Semma in 2019, which provided the foundation for VX-880, and the $320 million takeover of ViaCyte in 2022. Earlier this year, the company secured manufacturing technology through a $780 million licensing deal with TreeFrog Therapeutics.
The field saw its first FDA approval last year when CellTrans received clearance for Lantidra (donislecel), an islet cell therapy derived from deceased donors. Like VX-880, Lantidra requires immunosuppressive drugs and is approved for patients severely affected by hypoglycemic events.
Other competitors include Canadian company Sernova, which is conducting phase 1/2 trials of islet cells in its proprietary Cell Pouch device. According to recent company updates, the first patient treated with this approach has maintained insulin independence for four years with normal HbA1c levels.
Path to Phase 3 and Potential Approval
Based on the strength of the phase 1/2 data, researchers are now advancing to a phase 3 trial with a planned enrollment of approximately 50 adults. Unlike the current study, which focused on elimination of severe hypoglycemia and HbA1c reduction, the phase 3 trial will use insulin independence as its primary endpoint.
If successful, VX-880 could represent a paradigm shift in type 1 diabetes treatment, potentially offering a functional cure for a condition that currently requires lifelong insulin therapy and careful monitoring for most patients.
