BCG is a stable, ready-to-inject, aqueous formulation of human glucagon for hypoglycemia rescue therapy. In this randomized, double-blind, crossover trial we investigated the safety and efficacy of two BCG formulations vs. a commercially available glucagon (GlucaGen® HypoKit, GEN) in 27 patients with type 1 diabetes who received single subcutaneous doses of 1 mg of BCG1, BCG2 or GEN under insulin-induced hypoglycemic conditions (plasma glucose (PG)<60 mg/dl). Both BCG formulations were safe and well tolerated with the most frequent adverse event being mild nausea with both BCGs and GEN. Both BCGs quickly restored PG of ≥ 70 mg/dl after hypoglycemia (BCG1 11.5±5.0 min; BCG2 10.0±3.5 min; GEN 7.3±1.8 min, p<0.001 vs. BCG1 and BCG2). PG≥70 mg/dl was reached within 30 minutes by all but one patient with both BCGs and the mean PG increase at 15 minutes was 29±17 mg/dl with BCG1, 36±16 mg/dl with BCG2 and 47±11 mg/dl with GEN (p<0.001 vs. BCG1 and BCG2). In conclusion, the BioChaperone technology allows the formulation of stable ready-to-use liquid formulations of human glucagon suited for rescue therapy of severe hypoglycemia with only slightly slower effects than GEN. Disclosure S. Glezer: Stock/Shareholder; Self; Sanofi. Stock/Shareholder; Spouse/Partner; Sanofi. Employee; Self; ADOCIA, Novo Nordisk Inc.. Employee; Spouse/Partner; Pfizer Inc., Teva Pharmaceutical Industries Ltd.. Stock/Shareholder; Spouse/Partner; Teva Pharmaceutical Industries Ltd.. U. Hovelmann: None. S. Teng: Employee; Self; ADOCIA. D. Lamers: None. M. Odoul: Employee; Self; ADOCIA. Stock/Shareholder; Self; ADOCIA. J. Correia: Employee; Self; ADOCIA. Stock/Shareholder; Self; ADOCIA. E. Zijlstra: Speaker's Bureau; Self; Novo Nordisk A/S. Other Relationship; Self; Novo Nordisk A/S. M. Gaudier: Employee; Self; ADOCIA. Stock/Shareholder; Self; ADOCIA. O. Soula: Board Member; Self; ADOCIA. Stock/Shareholder; Self; ADOCIA. Employee; Spouse/Partner; ADOCIA. D. Duracher: Employee; Self; ADOCIA. Stock/Shareholder; Self; ADOCIA.