NEW ORLEANS – Two patients with type 1 diabetes have now experienced improved blood glucose control with Vertex Pharmaceutical’s investigational allogeneic stem cell–derived islets (VX-880), with the first person now completely insulin independent at 9 months post transplant.
Prior to the procedure, both patients had hypoglycemic unawareness and had experienced multiple episodes of severe hypoglycemia, conditions considered severe enough to justify the risk of immune suppression (which is required for such stem cell–derived islet transplants as they are “foreign” to the recipient).
Dr. James Markmann
The first patient, a 64-year-old man with type 1 diabetes for more than 40 years, now has a hemoglobin A1c in the normal range without taking any insulin more than 9 months after the procedure. The second, a 35-year-old woman with type 1 diabetes for 10.7 years, experienced a 30% reduction in insulin use and significant increased time spent in target glucose range, by 5 months post transplant. Both patients were given just half the targeted VX-880 dose.
Data for those two patients – the first in Vertex’s phase 1/2 multicenter, single-arm, open-label clinical trial of VX-880 – were reported at the annual scientific sessions of the American Diabetes Association, by James F. Markmann, MD, PhD.
He has been transplanting pancreatic islet cells from deceased donors into humans via infusion into the hepatic portal vein for over 20 years.
Transplantation of pancreatic islet cells obtained from cadavers have been shown to eliminate severe hypoglycemia and improve glycemic control in patients with type 1 diabetes, but they’re limited in quantity and are of variable quality. Islets that are manufactured via differentiation from human pluripotent stem cells represent an alternative, explained Dr. Markmann, chief of the division of transplant surgery at Massachusetts General Hospital, Boston.
“This is a new area. ... We hope this will be the same or potentially better. With stem cell–derived islets the quality, consistency, and reliability might produce a better result than with cadaveric islets,” he commented during a press briefing here.
A third patient has recently received the full targeted VX-880 dose but was not part of the current report. The planned enrollment is 17 patients. The trial is currently on clinical hold per the Food and Drug Administration concerning the criteria around dose escalation, but Vertex is working with the FDA to sort that out. Meanwhile, enrollment remains open in Canada, Dr. Markmann said.
In answer to a question about how patient 1 is doing now, Dr. Markmann replied, “He’s doing great. He’s probably the most appreciative patient I’ve ever met. His life was being destroyed by diabetes. He couldn’t work. He crashed his motorcycle from [low blood sugar]. He really was tremendously appreciative that he could participate.”
When Dr. Markmann explained the potential uncertainties and risks to the patient prior to the procedure, the patient replied: “I want to participate. If I die from this and I help somebody else I’d be happy, but I can’t go on living the way I’m living.”
“These people really suffer and this, I think, brings hope to them,” Dr. Markmann said.