Objective: We evaluated glycemic outcomes at two glucose targets with each of two configurations (bihormonal and insulin-only) of the bionic pancreas (BP) in the setting of standardized exercise in adults with type 1 diabetes.

Methods: 20 participants completed a double-blinded, placebo-controlled (glucagon vs. placebo) , random-order, cross-over trial comparing the bihormonal (BH) and insulin-only (IO) configurations of the BP, each using two glucose targets (1 and 130 mg/dl) ; each arm lasted three days. On the last morning of each arm, fasted subjects exercised on a stationary bike with a heart rate of 120-140 bpm for ∼30 minutes. The primary outcome was number of subjects discordant between the BH and IO arms using the same glucose target for events with plasma glucose (PG) <60 mg/dl for more than minutes (McNemar's Test) . Secondary endpoints included the area over the glucose curve and <60 mg/dl and grams of carbohydrates given for hypoglycemic events (Wilcoxon Signed Rank Test) .

Results: When using the 130 mg/dl glucose target, there were no events with PG<60 mg/dl in either the BH or IO configurations; AOC <60 mg/dl was 0 min*mg/dl for both configurations and no carbohydrates were given. When using the 1mg/dl glucose target, three subjects in the IO arm had an event with a PG <60 mg/dl for more than minutes; no subjects had an event using the BH configuration (p=0.25) . Median AOC <60 mg/dl was 0 [0-0] min*mg/dl for both configurations (p=0.18) , and the median amount of carbohydrates required to recover from hypoglycemic events was 0 [0-0] grams for both configurations (p=0.56) .

Conclusions: Both configurations of the BP provided safe glycemic regulation using both glucose targets during exercise use. Larger studies will be needed to quantify differences in exercise outcomes between the IO and BH configurations of the BP.


L.E.Castellanos: None. C.A.Balliro: Consultant; Beta Bionics, Inc., Zealand Pharma A/S. J.Sherwood: None. M.Hillard: None. R.Selagamsetty: Employee; Beta Bionics, Inc. H.Zheng: None. F.El-khatib: Employee; Beta Bionics, Inc., Stock/Shareholder; Beta Bionics, Inc. E.Damiano: Other Relationship; Beta Bionics, Inc. S.J.Russell: Advisory Panel; ConvaTec Inc., Eli Lilly and Company, Consultant; Beta Bionics, Inc., Other Relationship; Beta Bionics, Inc., Research Support; Beta Bionics, Inc., Dexcom, Inc., Novo Nordisk, Zealand Pharma A/S, Stock/Shareholder; Companion Medical.


NIDDK (T32DK007028)

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