Helixmith said it would announce next month the cause of the data error in its global phase-3 trial on Engensis (VM202-DPN), a gene therapy to treat diabetic peripheral neuropathy (DPN).
Earlier, the company said the failure resulted from its drug mix-up between the placebo and the treatment.
Now, it is also weighing other possibilities, such as technical errors.
Helixmith CEO Kim Sun-young held an investor relations briefing at the company’s headquarters in Seoul, Thursday. “We have completed the trace analysis of all stored documents. We will be able to complete the investigation into the remaining possibilities and announce the results by Jan. 15,” Kim said.
In September, the company said it found an error in pharmacokinetic (PK) data of the global phase-3 trial on Engensis as treatment of painful diabetic peripheral neuropathy (PDPN). The company found VM202 in blood samples from placebo patients and some patients in the treatment group had lower-than-expected levels of VM202 DNA.
At the time, Kim said it was most likely that there could have been a drug mix-up between the treatment group and the placebo group.
At an urgent briefing on Sept. 24, Kim said, “We think a poorly managed hospital might have mixed up drugs. We will have our investigation and pursue litigation against the responsible institution.”
At a recent briefing, however, Kim seemed to weigh other possibilities, such as mistakes in technical analysis rather than the mix-up.
Kim suggested the possibility of PK data error in two scenarios – one where the drugs were mixed and the other with other possibilities.
If the drugs were mixed, it was due to one of the three possibilities: Labeling change at “Drug Product” (DP) firm that makes the final product of Engensis; “Drug Depot” (DD) made a mistake when labeling patents; or clinical institution mixed up the labeling.
The company said it was unlikely that DP or DD made a labeling mistake.
Other possibilities include technical mistakes in the laboratory: A mix-up between blood samples or DNA samples in the laboratory; a mix-up between blood samples in the clinical institution; or environmental contamination of DNA in clinical and analytical laboratories.
As for the possibility of technical mistakes in the lab, Kim said, “Our analytical institution is one of the best in the U.S., but our PCR technology amplifies molecules up to 10 to the power of 13.”
As the company’s technology is sensitive to contamination of a molecule, there could be technical errors in the analytical institution, Kim said.
As hospitals store hundreds of blood samples at minus 70 degrees Celsius, there might have been labeling drops, mix-up of blood samples in clinical institutions, or DNA contamination in clinical and analytical environments, Kim added.
To track down the exact cause, Helixmith is collecting blood samples and residual DNA from clinical sites for further pharmacokinetic analysis.
“We submitted data to the institutional review board and expect that we will get the nod to pursue approval soon,” Kim said. “We are eliminating each possibility through experiments, and we are nearly at the end.”
Helixmith plans to submit the final report of the phase-3 trial, including its investigation results, to the U.S. FDA in February.