Safety, Tolerability, and Pharmacokinetics of SAB-185 in Healthy Participants

There were 4 treatment groups and 1 control group. Cohort 1 received 1 dose of SAB-185 at 10 mg/kg per dose. Cohort 2 received 1 dose of SAB-185 at 25 mg/kg, Cohort 3 received 2 doses of SAB-185 at 25 mg/kg each 7 days apart, and Cohort 4 received 1 dose of SAB-185 at 50 mg/kg per dose. All the doses were prepared at the site by the pharmacy staff or designee for delivery to the clinical staff for administration, per the site's SOPs.

Inclusion criteria

Subjects must meet all of the following criteria for inclusion:

• 18-60 years of age
• Able to understand the study and comply with all study procedures
• Agrees not to participate in any other trial of an investigational product during the study period
• Willing and able to provide written informed consent prior to the start of any study related activities
• In good health in the opinion of the site principal investigator as determined by vital signs, medical history, physical examination and clinical laboratory tests
• If female, meets at least one of the following reproductive risk criteria

• Post-menopausal for at least 12 months
• Use of one or more of the following highly effective contraceptive methods for at least 90 days following the last dose of study product: combined estrogen and progestogen containing or progestogen-only hormonal contraception, intrauterine device (IUD), intrauterine hormone-releasing system, surgical bilateral tubal occlusion
• Vasectomized sole sexual partner who has received medical assessment of the surgical success
• Subjects agree to sexual abstinence (refraining from heterosexual intercourse for at least 90 days following the last dose of study product) if not using birth control or condoms for males.

Exclusion criteria

• Female subjects with positive pregnancy test, breastfeeding, or planning to become pregnant/breastfeed during the study period.
• Treatment or participation in another clinical trial of any other investigational agent within 30 days prior to enrollment.
• Use of other drugs that, in the opinion of the investigator, could complicate analysis of SAB-185.
• Subjects with the following risk factors:

• Compromised immune system including confirmed diagnosis of current cancer under treatment, inherited deficiencies of the immune system, immune suppressing medication, or other conditions causing leukopenia or neutropenia
• Known autoimmune condition requiring therapy more intensive than intermittent non-steroidal anti-inflammatories in the prior 6 months (for example: rheumatoid arthritis, lupus, inflammatory bowel disease)
• Chronic respiratory disease including COPD, emphysema, cystic fibrosis, pulmonary hypertension, or other chronic condition that requires the routine use of supplemental oxygen
• Chronic asthma requiring the use of oral steroids or hospitalization in the last six months
• Renal failure or renal insufficiency requiring dialysis
• Congestive heart failure or significant atherosclerotic disease (coronary artery disease or peripheral vascular disease)
• Hypertension, diabetes, those currently vaping or smoking or with a history of chronic smoking, and those with BMI > 35 kg/m2
• Receipt of pooled immunoglobulin or plasma in past 30 days
• Any other underlying medical (cardiac, liver, renal, neurological, respiratory) or psychiatric condition that in the view of the investigator would preclude use of SAB-185
• Known IgA deficiency or previous allergic reaction to intravenous immunoglobin (IVIG)/subcutaneous immunoglobin (SCIG)
• Positive screening test for hepatitis B virus surface antigen, hepatitis C virus antibody, or HIV antibody
• Positive screening test for rheumatoid factor
• History of COVID-19
• Positive FDA-authorized screening test for serum SARS-CoV-2 antibody or presence of SARS-CoV-2 on nasopharyngeal or oropharyngeal swab by FDA-authorized RT-PCR
• History of allergy, anaphylaxis, or severe reaction to beef products (including milk and gelatin).