REGEN-COV

The antibody cocktail was generally well tolerated and reduced viral load in COVID-19 outpatients, especially those with high viral loads at baseline and patients whose immune response had not been initiated at the time of antibody administration. Sample size: 84 (high dose) + 80 (low dose) + 88 placebo (completed the trial). Dosage: 2.4 g (low) or 8 g (high). Endpoints: Change in viral load; proportion of patients with a COVID-19-related hospital visit by day 29.

This study demonstrates that a combination of noncompeting antibodies not only provides full coverage against currently circulating variants but also protects against emergence of new such variants and their potential seeding into the population in a clinical setting.

REGN-COV2 displayed in vitro inhibition of SARS-CoV-2 Spike-pseudotyped virus infection for all tested emergent Spike variants (B.1.1.7, B.1.351, and P.1).

In a patient with X-linked agammaglobulinemia, clinical/immunological response to anakinra was not satisfactory. Long-term immunosuppression led to a secondary pulmonary infection. Administration of REGN-COV2 formulation led to SARS-CoV-2 PCR negativity and COVID-19 convalescence. Sample size: 1. Dosage: 1200 mg of REGN10933 and 1200 mg of RGN10987. 

The combined formulation (REGEN-COV) is predicted to display synergy of its components in RBD-binding capacity. 

The antibody cocktail administered prophylactically or therapeutically reduced viral loads in the lower and the upper respiratory tracts and mitigated pathological changes in rhesus macaques. Alleviation of weight loss, lung pathology and lung viral loads were observed in a hamster model. 

The antibody was administered in a child with inborn deficiency in interferon response. The treatment led to a positive clinical outcome. Sample size: 1. Dosage: 600 mg IV. 

Most of the Immunodeficient patients with persisting COVID-19 treated with the antibody cocktail experienced rapid viral clearance and clinical improvement. Serious adverse reactions were mostly unlikely to be treatment-related. Sample size: 64. 

Compared to placebo, early treatment with the antibody cocktail in patients with risk factors for COVID-19 progression into a severe disease significantly reduced COVID-19 related hospitalization or death by day 29. The treatment also reduced the median time to the resolution of symptoms and reduced viral load faster. Severe adverse reactions were more frequent in the placebo groups. Sample size: 1355 + 1341 placebo (2400 mg group) and 736 + 748 placebo (1200 mg group) + 10122 (8000 mg - only certain analyses). Dosage: (8000 mg,) 2400 mg or 1200 mg IV. Main outcome: Hospitalization or all-cause death through day 29.

Compared to placebo, early subcutaneous administration of the antibody cocktail in individuals with household contact with SARS-CoV-2 positive persons led to significant decrease of rate of symptomatic COVID-19. The symptomatic COVID-19 and the duration of high viral loads in the treated individuals, if present, were significantly shorter. Sample size: 753 + 752 placebo. Dosage: 12000 mg subcutaneously. Main outcome: Symptomatic COVID-19 in 28 days.

The treatment of pregnant women was safe. Although its efficacy was not statistically significant, based on the results and other observations, the author advocate for the use of the antibody cocktail in pregnant patients. Sample size: 36 + 50 control. Main outcome: Perinatal outcomes, safety, and the clinical course of COVID-19.

From a serological point of view, REGEN-COV provides a therapeutic and prophylactic benefit, which is also supported by a high titer of IgGSP (immunoglobulin targeting spike protein).

Early treatment with REGEN-COV may prevent clinical deterioration in SARS-CoV-2 infection leading to the development of COVID-19 in hematological patients. The effectiveness of the drugs varies depending on the variants of the virus (especially B.1.1.529). Sample size: 15. Dosage: Single infusion of casirivimab (600 mg) and imdevimab (600 mg). 

REGEN-COV treatment has been shown to be effective in high-risk patients. Sample size: 696 + 696 control. Dosage: 1200 mg (casirivimab + imdevimab). 

REGEN-COV can be given safely to patients on dialysis who have severe disease and do not need extra oxygen. Sample size: 1. Dosage: 1200 mg REGEN-COV on day 2. and 1200 mg/10 mL REGEN-COV dissolved in 100 mL saline for 30 min after dialysis. 

Pediatric heart transplant patients were able to tolerate REGEN-COV without experiencing any complications, and no changes to their immunosuppressive treatment were required. Sample size: 6. 

Based on in vitro, animal model, and observational data, the antibody cocktail was effective against all variants tested and no escape mutations were observed. Sample size: 1000. 

Patients who are at high risk for SARS-CoV-2 infection and were treated with the REGEN-COV antibody cocktail, even if infected with the Delta variant, had quicker symptom resolution and lower levels of the virus in their body. Sample size: 208 + 78 control. Dosage: 600 mg casirivimab + imdevimab/100 ml saline. 

270 days after the first diagnosis, treatment with REGEN-COV proved to be effective. After being vaccinated with the Pfizer-BioNTech vaccine against COVID-19, the virus was completely eliminated within the following month. Sample size: 1. Dosage: The first dose of 2.4 g, after that at a higher dose of 8 g (4 g for each of casirivimab and of imdevimab) was infused six weeks later. 

Administering REGN-COV2 in a timely manner to kidney transplant recipients who cannot receive or have a weakened antibody response to vaccinations, may help prevent them from developing severe illness if they test positive for COVID-19. Sample size: 14. Dosage: A single-dose infusions of casirivimab 1200 mg and imdevimab 1200 mg. 

Treatment with monoclonal antibody led to a decrease in hospital usage, particularly if administered within a few days after the onset of symptoms. Sample size: 707 + 1709 control. Main outcome: Hospitalization with a diagnosis of COVID-19 until the 30th day.