Biotech experts raised a safety concern for Invossa-K, a degenerative arthritis treatment suspended by Kolon Life Science, saying the drug might have used cancerous cell lines called GP2-293 cells.
No single study or case has shown what 293 cells will do to the human body, they said.
Experts from the biopharmaceutical industry and scholars said the fact that 293 cells were injected into the human body was a shocking revelation.
GP2-293 cells that Kolon Life Science admitted to having mislabeled are abnormal cells transformed for unlimited proliferation like cancer cells. They are different from normal cells derived from the cartilage.
GP2-293 cells originate from human embryonic kidney 293 (HEK-293) cells, which are commonly used for research. HEK-293 cells are extracted from aborted fetal kidney cells. Unlike normal cells that die after a certain period, they can proliferate as quickly as cancer cells.
The vitality of HEK-293 cells is stronger than that of normal cells. In a research lab, HEK-293 cells are used to mass produce viruses, and the cells are discarded entirely because it is unpredictable what kind of mutations the cancerous cells could cause within the body when injected.
The U.S. National Center for Biotechnology Information (NCBI) said in a paper that “HEK-293 cells, which rapidly changes the expression of cancer-related genes, cause chromosomal instability and exacerbates tumorigenicity.”
A researcher at a cell therapy developer said, “Kolon Life Science has experimented to see what would happen if 293 cells were injected into the body, although it must have been unintentional.”
The Ministry of Food and Drug Safety agreed.
“Although it is possible to produce viruses or proteins using 293 cells, it is impossible to develop the cells into a medical treatment. Invossa was the first case in the world to use 293 cells for treatment,” an official at the food and drug safety ministry said.
The official noted that the ministry could not guarantee the safety of the now-suspended drug and that it was conducting a survey on all patients who have been treated with Invossa.
“We are collecting all cases of side effects because unexpected adverse drug reactions may occur,” he said.
Kolon Life Science said Invossa was safe because it has blocked potential tumorigenicity through radiations and apoptosis tests.
Besides, transformed cells (TC) were merely mediators for the expression of the TGF-β1 gene, and they did not play any other role, the company argued.
Kolon emphasized that there was no safety-related side effect reported among 3,548 patients who have been treated with Invossa during 11 years from clinical trials to date.
As Invossa’s ingredients passed clinical trials and approval procedures by proving the safety and efficacy, the issue was just a mislabeling, not a change of the elements, the company said.
However, the company was being too naïve about the safety concern, an industry source said.
A researcher at a biotech company said the concern is grave because the company does not have any reference data on what impact 293 cells will have on the human body. “Having no problem at the moment does not mean that it will be okay several years later,” the researcher said.
In fact, 96 percent of the 3,548 patients received Invossa injections after the market release, giving only 1.4 years for observation.
Scholars also said they were worried about the injections of 293 cells into the patients.
“If they didn’t have any problems using 293 cells, why did they go through the complicated process of separating the cells and putting them back into the cartilage cells,” a university professor said. “Even if radiation prevented a fatal problem, reporting to the regulator that the company would use 293 cells for treatment would have made the company fail to win drug approval.”