The government has decided to nullify Invossa-K’s license effective next Tuesday, but the company expects the U.S. Food and Drug Administration to allow it to resume phase-3 trial on the gene therapy for knee osteoarthritis.

Kolon Life Science said Wednesday it planned to correct the labeling of the cell ingredient of Invossa’s second fluid as kidney-derived cells (GP2-293 cells), instead of cartilage-derived cells, in the application for the U.S. trials of Invossa.

Although the controversy persists over GP2-293 cells’ tendency to cause tumors, the company still uses the same ingredient, and it already had proved Invossa’s safety and efficacy through phase-1 and phase-2 clinical data, Kolon said.

“The FDA may also think it ‘strange’ to tell us we need to do clinical trials all over again because we used the same ingredient in the phase-1 and phase-2 studies. The FDA seems to regard Invossa trials in the U.S. different from those sold in Korea,” Kolon Life Science CEO Lee Woo-sok said.

Invossa products for phase-3 trials in the U.S. are different from Invossa sold in Korea, in the number of cells, primary and secondary endpoints, and cell death process, he added.

Lee refuted a view that it is unlikely the Korean and the U.S. regulators will have different opinions over the same drug. “We are positive that we will resume the phase-3 study in the U.S. We will submit additional data required for the resumption of the trial,” he said.

Kolon is expected to submit the application for the trial resumption to the FDA around July 15. If the company decides to avoid the peak summer vacation season, the submission might be pushed back further.

However, Kolon does not expect to win the FDA nod for the resumption in a single try. The FDA is expected to review the submitted data for about a month and consider the Invossa fiasco in Korea, Lee said.

“If the FDA demands back-up data, the resumption might be delayed. We don’t expect the FDA to grant us the green light in just a month,” he said.

Kolon will announce a comprehensive measure to secure the safety of patients who have been treated with Invossa, on Thursday.