Korean researchers have published the first cohort study result for Celltrion’s Regkirona, a Covid-19 treatment, an antibody therapy that selects and mass-produces neutralizing antibodies from recovered patients via cell culture.
The Ministry of Food and Drug Safety approved the drug last September after the company confirmed that Regkirona reduced the severe morbidity rate by 72% and shortened the clinical recovery period by 4.12 days compared to the placebo group. in clinical phase 3 in which 434 patients participated.
However, Regkirona has been embroiled in controversy over its effectiveness in phase 2 clinical trials.
The research team, led by Pusan National University College of Pharmacy researcher Park Soo-shin, launched a cohort study to see if there was any efficacy. The researchers followed the medical records of Covid-19 patients hospitalized between December 1, 2020 and April 16, 2021, until death or discharge.
The study ended on May 14, 2021, and among mild high-risk Covid-19 patients, the team observed prognosis by dividing patients into those who received Regkirona and those who did not. received.
Of the 1,617 patients hospitalized during the study period, 970 patients (60%) were eligible for Regkirona, of whom 377 (38.9%) received Regkirona and 593 did not receive the treatment. As a result of the analysis, the number of multi-cause deaths or worsening of disease in the treatment group was only 19 (5%), while the number in the no-drug group was 81 (21 .5%).
The team confirmed that the length of hospitalization was also shorter for the treated group (11.9 ± 3.3 days) compared to the untreated group (13.7 ± 5.4 days).
In terms of safety, some haematological side effects were more common in the Regkirona-treated group but were not serious, and other side effects were similar.
“This study is significant in that it confirmed significant clinical effects as the sole agent to neutralize Covid-19 in Korea,” the research team said. “Although sufficient evidence for routine clinical application was lacking, we hope that this real evidence will serve as the basis for effective treatment of Covid-19.”
While research on the therapeutic effect of Regkirona on variants is currently ongoing, further research is needed on the effectiveness of Regkirona in treating variants in real clinical practice, the team added.
Meanwhile, as data has proven the mechanism of action using neutralizing antibodies in the blood of recovered people, such as shortening hospital stay and reducing disease worsening, industry experts s expect the research data to help Celltrion develop its inhaled cocktail treatment to treat the variants.
The company developed the inhaled antibody treatment for Covid-19 after the government decided to stop using Regkirona due to reduced efficacy against the Omicron variant on February 24.
According to an industry insider, despite the study’s limitations before the Delta and Omicron outbreak, it still has significance in demonstrating the mechanism of action of an antibody therapy using the blood of a female patient. healed person.
“This is important because the company can also select neutralizing antibodies from recovered Omicron patients and rapidly mass-produce them through gene cloning due to the characteristics of therapeutic antibodies,” the insider said.
Celltrion is currently developing an inhaled cocktail antibody treatment that adds CT-P63, a candidate for the treatment of Covid-19, which the company confirmed was safe in a clinical trial earlier this year.
Celltrion has finalized the submission of Phase 3 clinical trial plans for inhaled cocktail antibody therapy in three countries – Bosnia, Serbia and North Macedonia – and plans to expand the number of countries to enroll 2,200 patients with mild and moderate Covid-19 in order to prove the efficacy and safety of inhaled therapy.
Celltrion plans to expand clinical trials in countries where patient recruitment and clinical progress are smooth, given the clinical trial environment, such as the spread of viral mutations.
The company expects inhaled antibody therapy to become an optimized platform to respond to variants by co-administering CT-P63, which has neutralizing capacity against these variants.