39-LB: A Comparison of Insulin Glargine U300 and Insulin Degludec around Spontaneous Exercise Sessions in People with Type 1 Diabetes—The ULTRAFLEXI-1 Study
Authors: MOSER OTHMAR , MUELLER ALEXANDER , ABERER FELIX , AZIZ FAISAL , KOJZAR HARALD , SOURIJ CAREN , OBERMAYER ANNA M. , ABBAS FARAH M. , BIRNBAUMER PHILIPP , ECKSTEIN MAX L. , HÖNGER LUKAS , LENZ JACQUELINE , MURSIC INES , STERNAD CHRISTOPH , ZANKER MATTHIAS , ZIKO HARIS , PFERSCHY PETER N. , TRIPOLT NORBERT J. , SOURIJ HARALD 
Published: May 2022

Background and aims: Regular physical activity and exercise represent a corner stone in the treatment of type 1 diabetes (T1D) , however, exercise-induced hypoglycemia remains the major barrier to a physically active lifestyle. Therefore, the ULTRAFLEXI-1 study compared two basal insulin analogues, Glargine 300U/ml (IGlar U300) and Degludec (IDeg) , in two different doses (100% and 75% of the regular dose) when used around spontaneous exercise sessions in adults with T1D.
Methods: We performed a randomized, single-center, four-period, cross-over trial (EudraCT: 2019-003209-89) and included adults with T1D treated with multiple daily insulin injections and an HbA1c ≤10% (≤86 mmol/mol) . In each of the four 2-weeks-periods, participants attended six spontaneous evening cycling sessions (60 minutes, moderate intensity) . The days of exercising were randomized and announced at 8 A.M. to the participants. The basal insulin used on the exercise days during the four periods were: IGlar U300 100% or 75% of the regular dose or IDeg 100% or 75%, respectively. 100% of the regular basal insulin dose was used at all non-exercise days. CGM was performed using a blinded Dexcom G6 device. The primary outcome was TBR (&lt;70 mg/dl) during the six 24-hour post-exercise periods in the four trial arms. The difference in TBR between 100% IGlar and 100% IDeg or 75% IGlar and 75% IDeg was analyzed in hierarchical order using the repeated measures linear mixed model.
Results: 25 people were enrolled (14 male) , aged 41.4±11.9 years, with a mean diabetes duration of 16.8±10.4 years and a mean HbA1c of 7.5±0.8%. (59±9 mmol/mol) . Mean TBR during the 24-hour periods following the exercise sessions was 2.71±2.56% for IGlar U300 (100%) and 4.37%±3.43% for IDeg (100%) (p=0.025) as well as 2.28±2.67% for IGlar U300 compared to 2.55 ±2.87% with IDeg when using the 75% dose on exercise days (p=0.720) .
Conclusion: Time spent in hypoglycemia after spontaneous exercise sessions was significantly lower in people with type 1 diabetes receiving IGlar U300 as compared to IDeg when the 100% dose was used.

Disclosure
O. Moser: Research Support; Dexcom, Inc., Sanofi, Speaker’s Bureau; Medtronic. M. L. Eckstein: None. L. Hönger: None. J. Lenz: None. I. Mursic: None. C. Sternad: None. M. Zanker: None. H. Ziko: None. P. N. Pferschy: None. N. J. Tripolt: None. H. Sourij: Advisory Panel; AstraZeneca, Bayer AG, Boehringer Ingelheim International GmbH, Daiichi Sankyo, Eli Lilly and Company, Merck Sharp & Dohme Corp., Novo Nordisk, Research Support; Boehringer Ingelheim International GmbH, Sanofi, Speaker’s Bureau; Amgen Inc., AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck Sharp & Dohme Corp., Novartis AG, Novo Nordisk. A. Mueller: None. F. Aberer: Other Relationship; Amgen Inc., Boehringer Ingelheim International GmbH, Sanofi. F. Aziz: None. H. Kojzar: None. C. Sourij: None. A. M. Obermayer: None. F. M. Abbas: None. P. Birnbaumer: None.

Funding
Sanofi-aventis (DCV-2018-12349)