|Graphics by Bae So-young|
By Nam Hyun-woo
Celltrion has revealed positive Phase 2 clinical trial results for its COVID-19 treatment Regkirona, also known as CT-P59, raising expectations that the firm will get conditional approval for its use here as early as this month.
The treatment is anticipated to be a new addition to the arsenal of drugs that can be used to fight the coronavirus in and outside Korea, but experts and analysts said Regkirona and other COIVID-19 treatments will not likely be game changers as they will play a limited role in preventing patients with mild to moderate symptoms from progressing to severe stages of the disease.
They stressed that reaching herd immunity, a level large enough so that the overall population is protected, requires vaccination, the most feasible way of seeing a turnaround in the pandemic, but Korea appears to have missed out in the timing to develop its own COVID-19 vaccines.
Celltrion announced the Phase 2 trial results of Regkirona on Jan. 13. In the trial conducted on 327 patients in Korea, Romania, Spain and the United States, Regkirona reduced the number of patients with mild to moderate COVID-19 symptoms from progressing to the severe stage requiring hospitalization by 54 percent compared to a placebo, the company said.
Celltrion added that Regkirona showed a significantly lower level of viral load seven days after injection, while it required 10 days for the placebo group to reach the same level. Analysts said this is comparable to other COVID-19 treatments which earned Emergency Use Authorization from the U.S. Food and Drug Administration, meaning the chances are high that Regkirona will get approval not only in Korea but also other countries.
Despite the favorable outcome, investor sentiment moved adversely. A day after Celltrion announced the results, the company's share price dropped 7.6 percent from the previous day's trading to end at 352,000 won, despite the benchmark KOSPI remaining nearly flat. Mixed interpretations were raised over this, with some saying investors were profit taking, while others claimed it was an expression of disappointment in the treatment's limited role.
"With the treatment, Celltrion showcased it was not a company limited to making biosimilar drugs, but that it could develop its own novel drugs," Hana Financial Investment analyst Sun Min-jeong said.
"However, there is a limit in expecting Regkirona to directly improve Celltrion's earnings, given the relatively small number of patients in Korea," she said. "The company will certainly export this drug to the U.S. and Europe, but other antibody treatments, such as Regeneron's cocktail, is recording a mere 20 percent prescription rate. This means it is difficult to expect antibody treatments to become a game changer in treating COVID-19."
Experts also expressed similar opinions. Prof. Kim Woo-joo at Korea University's Infectious Disease Department said Regkirona and other antibody treatments were playing limited roles in reducing the number of aged or chronic lung-disease patients visiting emergency rooms or getting hospitalized due to COVID-19.
"If any COVID-19 treatment were to be described as a game changer, it has to be effective in alleviating symptoms in severe patients or reducing the reproductivity rate of the disease," Kim said. "As Celltrion said in its Phase 2 results, the treatment has efficacy in preventing patients with mild to moderate symptoms from progressing to severe stages, which is not far different from other treatments from Eli Lilly and Regeneron."
In October, the U.S. government officially ended a study testing Eli Lilly's antibody drug for patients hospitalized with COVID-19, after experts reviewed interim data on 326 patients and decided there was no clinical value in treating them compared to a placebo group.
At the time, Lilly said the U.S. government was continuing a separate study testing the antibody drug in mild to moderate patients to prevent hospitalization and progression.
The New York Times earlier reported that the U.S. federal government has on hand nearly 532,000 doses of the two drugs, and 55 percent of them had been shipped out as of last month. But early data collected from hospitals by the federal government suggest that they only about 20 percent of these were administered to patients.
"Even if Celltrion's drug has the best efficacy among available COVID-19 treatments, what will be the big difference between the two drugs," Kim said. "Despite the precedents of other antibody treatments, politicians are trumpeting this as a significant shift in the situation, pumping up public expectation as if the pandemic may end when a treatment is administered."
The Moon Jae-in administration is under growing criticism over its belated efforts to secure vaccines compared to other developed nations. Against this backdrop, the government and the ruling Democratic Party of Korea are underscoring the potential of Celltrion's treatment and COVID-19 vaccines under development by domestic companies, which pundits say are efforts to counter the criticism.
However, doctors who participated in Regkirona's Phase 2 trials remain cautious about the drug's role being exaggerated.
During a Jan. 14 radio interview, prof. Uhm Joong-sik of Gacheon University Gil Medical Center, who led the Phase 2 trials, said that the role of antibody drugs and other types of COVID-19 treatments was "curing those who are infected with the virus, and a dramatic turnaround in the pandemic will only be able through prevention."
Kim also said a turnaround will be possible when Korea reaches herd immunity, and this will likely be demonstrated first by Israel, whose vaccination campaign is the world's fastest. The Israeli Health Ministry said 19.5 percent of the population has been vaccinated to date, according to recent overseas reports.
"Korea has managed to secure 56 million doses of vaccines from overseas pharmaceutical companies, but those vaccines' durations are still unknown, meaning securing our own vaccine is still important," an official at a domestic biotech company said. "Encouraging domestic firms to develop a vaccine seems to be more important than celebrating a success in developing a treatment."
In Korea, there are four firms and one institution that have COVID-19 vaccines in early clinical trials ― Genexine, SK Bioscience, Cellid, GeneOne Life Science and the International Vaccine Institute. SK Bioscience is in a Phase 1 study, while the four others are in Phase 1/2a, meaning they are running Phase 1 and 2a trials simultaneously.