Vertex shares additional updates on zimislecel in type 1 diabetes

Vertex Pharmaceuticals shared an additional look at data from the Phase 1/2 FORWARD clinical trial, investigating the use of zimislecel for the treatment of type 1 diabetes complicated by severe hypoglycemic events (SHEs).

Zimislecel is an investigational treatment composed of stem-cell derived fully-differentiated islet cells.

Initial data from the FORWARD Study was reported at the American Diabetes Association Conference in June 2025 and published in the September 2025 issue of the New England Journal of Medicine.

These data showed that all 12 participants with at least one year of follow-up who received a full dose of zimislecel as a single infusion achieved ADA-recommended target HbA1c levels <7 per cent and >70 per cent time-in-range (70-180 mg/dL), and 10 out of 12 participants no longer required exogenous insulin.

Further data from the initial 12 participants was presented at the EASD Congress, showing that all participants achieved clinically meaningful changes in glycemic control, as measure by continuous glucose monitoring (CGM) metrics.

On average, subjects achieved time-in-range of 93 per cent, well above the ADA/EASD guideline target of 70 per cent.

Most adverse events (AEs) were mild or moderate in severity. There were no zimislecel-related serious AEs.

Two deaths occurred; both were reported previously and unrelated to zimislecel. Overall, the safety profile was consistent with the immunosuppressive regimen and islet infusion procedure.

These durable clinical benefits with elimination of SHEs, improved glycemic control, and freedom from exogenous insulin support the curative potential of zimislecel, the first and only allogeneic, stem-cell derived, islet cell therapy in pivotal development.