Vertex Announces Positive Day 90 Data for the First Patient in the Phase 1/2 Clinical Trial Dosed With VX-880, a Novel Investigational Stem Cell-Derived Therapy for the Treatment of Type 1 Diabetes - Seite 2

Efficacy Results

The patient was diagnosed with T1D approximately 40 years ago and has been dependent on exogenous insulin. In the one year prior to treatment, the patient experienced 5 severe, potentially life-threatening hypoglycemic episodes. Prior to treatment with VX-880, the patient’s insulin dose was 34 units per day and fasting and stimulated C-peptide levels were undetectable, indicating that the patient was not making their own insulin. Per the study protocol, the patient received half the target dose of VX-880 through a hepatic portal vein infusion in combination with a standard regimen of immunosuppressive agents.

Fasting C-peptide, HbA1c and 7-day average daily insulin dose were measured at various intervals after VX-880 treatment through Day 90. Fasting C-peptide was detected early after treatment with VX-880 and increased rapidly to Day 90. In parallel, HbA1c and daily insulin dose decreased over time.

Islet cell function was evaluated at baseline and at Day 90 using a Mixed Meal Tolerance Test (MMTT) with quantification of C-peptide levels, a direct marker for insulin production. At baseline prior to VX-880 treatment, fasting and stimulated C-peptide levels were undetectable, indicating no endogenous insulin production. At Day 90 after VX-880 treatment, fasting C-peptide was 280 pmol/L, reflecting restored basal insulin production and increased after MMTT stimulation to a peak of 560 pmol/L, indicating that VX-880 restored glucose-responsive insulin production. Also at Day 90, HbA1c improved from 8.6% at baseline to 7.2%, and daily insulin dose decreased from 34 units per day prior to treatment with VX-880 to an average dose of 2.9 units per day over a 7-day period at the Day 90 visit, reflecting a 91% decrease in daily exogenous insulin use.

Baseline and Day 90 Measures of Islet Cell Function for Patient 1
	Baseline before VX-880 infusion	Day 90 after VX-880 infusion
Fasting C-peptide (pmol/L)	Undetectable*	280
Peak Stimulated C-peptide with MMTT (pmol/L)	Undetectable*	560
HbA1c (%)	8.6	7.2