Celltrion’s Monoclonal Antibody Treatment for COVID-19, regdanvimab (CT-P59), Demonstrates Strong Neutralising Activity Against Delta Variant

• Pre- clinical data for regdanvimab (CT-P59) demonstrates strong neutralising activity against the Delta variant (B.1.617.2, first identified in India); results show 100% survival rate with virus eradication from all animals treated with therapeutic dosage of CT-P59
• Regdanvimab (CT-P59) also retained its neutralisation potency against the Lambda variant (C.37, first identified in Peru) using a pseudo-virus neutralisation assay
• Celltrion announces results from the global Phase III clinical trial of regdanvimab (CT-P59) at ECCMID 2021; data met all primary and key secondary endpoints

INCHEON, Korea--(BUSINESS WIRE)-- Celltrion Group today 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.¹

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% survival rate from COVID-19 compared to 0% 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)³, 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, Ph.D., 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% for patients at high- risk of progressing to severe COVID-19 and 70% 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.

Notes to Editors:

About Celltrion Healthcare

Celltrion Healthcare is committed to delivering innovative and affordable medications to promote patients’ access to advanced therapies. Its products are manufactured at state-of-the-art mammalian cell culture facilities, designed and built to comply with the U.S. FDA cGMP and the EU GMP guidelines. Celltrion Healthcare endeavours to offer high-quality cost-effective solutions through an extensive global network that spans more than 110 different countries. For more information please visit: https://www.celltrionhealthcare.com.

About regdanvimab (CT-P59)

CT-P59 was identified as a potential treatment for COVID-19 through screening of antibody candidates and selecting those that showed the highest potency in neutralising the SARS-CoV-2 virus. In vitro and in vivo pre- clinical studies showed that CT-P59 strongly binds to SARS-CoV-2 RBD and significantly neutralise the wild type and mutant variants of concern including the Alpha variant (B.1.1.7, first identified in the UK). In in vivo models, CT-P59 effectively reduced the viral load of SARS-CoV-2 and inflammation in lung. Results from the global Phase I and II clinical trials of CT-P59 demonstrated a promising safety, tolerability, antiviral effect and efficacy profile in patients with mild- to- moderate symptoms of COVID-19.⁴ Celltrion also has recently commenced the development of a neutralising antibody cocktail with CT-P59 against new emerging variants of SARS-CoV-2.

FORWARD LOOKING STATEMENT

Certain information set forth in this press release contains statements related to our future business and financial performance and future events or developments involving Celltrion/Celltrion Healthcare that may constitute forward-looking statements, under pertinent securities laws.

These statements may be identified by words such as “prepares”, “hopes to”, “upcoming”, ”plans to”, “aims to”, “to be launched”, “is preparing, “once gained”, “could”, “with the aim of”, “may”, “once identified”, “will”, “working towards”, “is due”, “become available”, “has potential to”, the negative of these words or such other variations thereon or comparable terminology.

In addition, our representatives may make oral forward-looking statements. Such statements are based on the current expectations and certain assumptions of Celltrion/Celltrion Healthcare’s management, of which many are beyond its control.

Forward-looking statements are provided to allow potential investors the opportunity to understand management’s beliefs and opinions in respect of the future so that they may use such beliefs and opinions as one factor in evaluating an investment. These statements are not guarantees of future performance and undue reliance should not be placed on them.

Such forward-looking statements necessarily involve known and unknown risks and uncertainties, which may cause actual performance and financial results in future periods to differ materially from any projections of future performance or result expressed or implied by such forward-looking statements.

Although forward-looking statements contained in this presentation are based upon what management of Celltrion/Celltrion Healthcare believes are reasonable assumptions, there can be no assurance that forward-looking statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Celltrion/Celltrion Healthcare undertakes no obligation to update forward-looking statements if circumstances or management’s estimates or opinions should change except as required by applicable securities laws. The reader is cautioned not to place undue reliance on forward-looking statements.

References

¹ World Health Organization. Coronavirus disease (COVID-19)/Media resources/Science in 5/Episode #45 - Delta variant. https://www.who.int/emergencies/diseases/novel-coronavirus-2019/media-resources/science-in-5/episode-45---delta-variant [Last accessed July 2021]
² Ryu DK., et al. Therapeutic effect of CT-P59 against SARS-CoV-2 South African variant. Biochemical and Biophysical Research Communications, Volume 566, 2021, Pages 135-140, https://doi.org/10.1016/j.bbrc.2021.06.016. [Last accessed July 2021]
³ Ryu DK., et al. Therapeutic efficacy of CT-P59 against P.1 variant of SARS-CoV-2. bioRxiv 2021.07.08.451696; doi: https://doi.org/10.1101/2021.07.08.451696
⁴ Celltrion Data on file

View source version on businesswire.com: https://www.businesswire.com/news/home/20210715006147/en/