Celltrion’s monoclonal antibody treatment for COVID-19 works against Delta variant: Study

Celltrion Group announced new results from an in vivo efficacy study showing that regdanvimab (CT-P59) has a strong neutralising effect against the rapidly spreading Delta variant (B.1.617.2, first identified in India).

According to the World Health Organization (WHO), the Delta variant has been reported in 96 countries becoming the most common variant.

The pre- clinical in vivo study assessed the neutralisation effect of CT-P59 against the Delta variant, using a clinically relevant dose. The study demonstrated that CT-P59 treatment results in a 100 per cent survival rate from COVID-19 compared to 0 per cent for the placebo group, with significant protection against body weight loss shown after viral challenge also seen. In addition, a therapeutic dosage of CT-P59 significantly reduced the viral load of SARS-CoV-2 and inflammation in the lungs compared to non-treated controls with virus eradication from all animals treated with CT-P59.

Taken together, CT-P59 has shown in vivo efficacy against Delta variant following Beta (B.1.351, first identified in South Africa)² and Gamma variant (P.1, first identified in Brazil), which was comparable to that against wild type SARS-CoV-2, thus demonstrating that despite the reduced in vitro neutralising activity against Variants of Concern (VOC), CT-P59 retained its therapeutic potency in in vivo setting.

The monoclonal antibody CT-P59 also demonstrated strong neutralising capability against the Lambda variant (C.37, first identified in Peru) in a cell-based pseudo- virus assay study performed by the National Institutes of Health (NIH), U.S.

“These new data are encouraging and reinforcing our body of both pre-clinical and clinical data,” said Dr HoUng Kim, Head of Medical and Marketing Division at Celltrion Healthcare. “The Delta variant is a highly transmissible and contagious variant that could prompt further waves of infection around the world. It is important to expand the arsenal of monoclonal antibody therapies that are hoped to remain effective against the emerging COVID-19 variants.”

Celltrion announced its full Phase III data at the 31^st European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) which took place online from 9 -12 July 2021. During the oral session, data showed regdanvimab (CT-P59) significantly reduced the risk of COVID-19 related hospitalisation or death by 72 per cent for patients at high- risk of progressing to severe COVID-19 and 70 per cent for all patients. In addition, patients who were treated with regdanvimab (CT-P59) reported a significantly shortened time to clinical recovery by at least 4.7 days for patients at high- risk of progressing to severe COVID-19 and by 4.9 days compared to placebo for all patients.