Single-dose Study to Evaluate Safety, Tolerability, and Pharmacodynamics of REMD-477 in Subjects With Type 1 Diabetes Mellitus

Inclusion Criteria: * Men and women between the ages of 18 and 60 years old, inclusive, at the time of screening; * Females of non-child bearing potential must be ≥1 year post-menopausal (confirmed by a serum follicle-stimulating hormone (FSH) levels ≥ 40 IU/mL) or documented as being surgically sterile. Females of child bearing potential must agree to use two methods of contraception; * Male subjects must be willing to use clinically acceptable method of contraception during the entire study; * Body mass index between 18.5 and 26.9 kg/m2, inclusive, at screening; * Diagnosed with Type 1 diabetes for greater than 2 years, based on clinical history or as defined by the current American Diabetes Association (ADA) criteria; * HbA1c ≥6.0 % but \<9.0 % at screening; * Fasting C-peptide \<0.2 ng/mL; * Current use of insulin pump and willing to use continuous glucose monitoring (CGM) system (e.g. DexCom) throughout the entire study; * ALT and/or AST within \<1.5x ULN at screening; * Serum amylase and lipase within normal limits at screening; * Able to provide written informed consent approved by an Institutional Review Board (IRB). Exclusion Criteria: * History or evidence of clinically-significant disorder or condition that, in the opinion of the Investigator, would pose a risk to subject safety or interfere with the study evaluation, procedures, or completion; * Significant organ system dysfunction (e.g., clinically significant pulmonary or cardiovascular disease, anemia \[Hemoglobin \<10.0 g/dL\], and renal dysfunction \[eGFR \<90 ml/1.73M2/min\]); * Any severe symptomatic hypoglycemic event associated with a seizure or requiring help from other people or medical facility in the past 6 months; * Current or recent (within 1 month of screening) use of diabetes medications other than insulin; * Use of steroids and/or other prescribed or over-the-counter medications that are known to affect the outcome measures in this study or known to influence glucose metabolism; * Smokes tobacco; * Known sensitivity to mammalian-derived drug preparations, recombinant protein-based drugs or to humanized or human antibodies; * History of illegal drug use or alcohol abuse within the last 6 months or a positive drug urine test result at screening; * History of pancreatitis, pancreatic neuroendocrine tumors or multiple endocrine neoplasia; * History of pheochromocytoma, or family history of familial pheochromocytoma; * Known or suspected susceptibility to infectious disease (eg, taking immunosuppressive agents or has a documented inherited or acquired immunodeficiency); * Positive for human immunodeficiency virus (HIV) antibodies, hepatitis B surface antigen (HbsAg), or hepatitis C antibodies (HepC Ab); * Participation in an investigational drug or device trial within 30 days of screening or within 5 times the half-life of the investigational agent in the other clinical study, if known, whichever period is longer; * Blood donor or blood loss \>500 mL within 30 days of Day 1; * Women who are pregnant or lactating/breastfeeding; * Regular exercise \>120 min/week within 14 days of Day 1; * Unable or unwilling to follow the study protocol or who are non-compliant with screening appointments or study visits; * Family history of multiple endocrine neoplasia. Other inclusion and exclusion criteria may apply.