Celltrion announces positive top-line results from global Phase III trial of regdanvimab (CT-P59), an anti-COVID-19 monoclonal antibody treatment

• Regdanvimab (CT-P59) (40mg/kg) achieved statistically significant and clinically meaningful results in four main endpoints including primary and three key secondary endpoints; the company anticipates full Phase III data to be released in the coming months

• 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

• Patients who were treated with regdanvimab (CT-P59) reported a significantly shortened time to clinical recovery by at least 4.7 days quicker for patients at high- risk of progressing to severe COVID-19 and by 4.9 days quicker compared to placebo for all patients

• According to the recently published article from Biochemical and Biophysical Research Communications, sufficient antiviral effect in B.1.351 variant (now classified by the WHO as Beta)-infected animals was confirmed with a clinical dosage of regdanvimab (CT-P59)1

Incheon, South Korea--(Antara/Business Wire)- Celltrion Group today announced top-line efficacy and safety data from the global Phase III clinical trial, demonstrating that anti-COVID-19 monoclonal antibody treatment candidate, regdanvimab (CT-P59), met all primary and key secondary endpoints in patients with mild- to- moderate symptoms of COVID-19 (n=1,315). Results showed that CT-P59 significantly reduced the risk of hospitalisation or death by 72% for patients at high- risk of progressing to severe COVID-19 up to Day 28, compared to placebo, meeting the primary efficacy endpoint [3.1 vs. 11.1 %, p-value< 0.0001]. CT-P59 also significantly reduced the risk of hospitalisation or death by 70% in all patients, meeting the first key secondary endpoint [2.4 vs. 8.0 %, p-value< 0.0001].

The trial also met the other key secondary endpoints, including faster and persistent reduction in symptom duration. Patients treated with CT-P59 (40mg/kg) recovered at least 4.7 days earlier than those in the placebo-treated patients [median 9.3 vs. minimum 14 days, p-value< 0.0001] for patients at high- risk of progressing to severe COVID-19. For all patients treated with CT-P59 (40mg/kg), patients recovered 4.9 days earlier than those in the placebo-treated patients [median 8.4 vs. 13.3 days, p-value< 0.0001].

Top-line results also showed CT-P59 to have a positive safety profile, with no clinically meaningful differences between patients treated with CT-P59 (40mg/kg) and placebo-treated patients. Infusion related reactions were mild and transient, with most patients recovering within 1~3 days.

“We continue to be challenged by the COVID-19 pandemic and new variants of concern,” said Dr. HoUng Kim, Ph.D., Head of Medical and Marketing Division at Celltrion Healthcare. “As many hospitals across the globe now exceed their ability to accommodate patients due to COVID-19, it is critical that we use every resource to reduce the burden on the healthcare system. This well-controlled trial provides conclusive results demonstrating that CT-P59 can improve outcomes in people with mild- to- moderate COVID-19 and also significantly reduce the risk of hospitalisation and death. We look forward to continuing to work with regulators around the world to make CT-P59 available to more patients in need.”

Therapeutic effect of CT-P59 against B.1.351 variant (first identified in South Africa, now classified by the WHO as Beta) was updated through the publication from Biochemical and Biophysical Research Communications. According to the article, in vivo ferret challenge studies demonstrated that a therapeutic dosage of CT-P59 was able to decrease B.1.351 viral load in the upper and lower respiratory tracts, comparable to that observed for the wild type virus.1

Celltrion plans to release full Phase III data in the coming months and plans to present the data at an oral session at the 31st European Congress of Clinical Microbiology & Infectious Diseases (ECCMID), which will take place online from 9 -12 July 2021.

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 US 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/en-us.

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 UK variant (B.1.17). 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-19.2 Celltrion also has recently commenced the development of a neutralising antibody cocktail with CT-P59 against new emerging variants of SARS-CoV-2. The research for Celltrion’s clinical trials was supported by a grant as part of the Korea Health Technology R&D Project from the Korea Health Industry Development Institute (KHIDI), funded by the ministry of Health & Welfare, Republic of Korea (grant number: HQ2xC00xx).

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1 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 June 2021]

2 Celltrion Data on file

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