[Kim Jin Soo, Edaily Reporter] South Korean diagnostic stocks, including Humasis, GC Green Cross MS, and Genematrix, rallied on Tuesday as investors reacted to a suspected plague exposure incident at a Russian research institute.

The gains came despite the fact that no South Korean diagnostic company is known to have a commercially available test specifically for plague, raising concerns that the rally may have been driven largely by speculative buying.

Meanwhile, Peptron’s stock plunged in after-hours trading after announcing that a technology evaluation agreement with Eli Lilly had ended without the commercial deal investors had anticipated.

Hanmi Science, the holding company of Hanmi Pharmaceutical, jumped about 15% in after-hours trading after South Korea approved Hanmi Pharmaceutical’s domestically developed GLP-1 obesity drug.

Diagnostic Stocks Rally on Plague Concerns

According to KG Zeroin’s MP Doctor, GC Green Cross MS, a major South Korean diagnostics company, closed up 26.89% at 4,200 won on Tuesday.

Humasis rose 19.77% to 3,120 won, while Genematrix gained 15.21% to 1,871 won. LabGenomics and Sugentech also climbed 7.85% and 6.8%, respectively.

The rally was largely attributed to concerns surrounding the death of a researcher at a plague laboratory in Russia.

According to foreign media reports, a 28-year-old female researcher working at a plague research institute in Russia’s Irkutsk region in Siberia died on October 2 from pneumonia of unknown origin. Local reports have raised the possibility that her death may have been linked to an incident last month in which a test tube containing Yersinia pestis—the bacterium that causes the plague—was broken.

Russian authorities quarantined and tested about 200 people who had been in contact with the researcher, but no additional confirmed cases have been reported so far. The World Health Organization has assessed the risk of spread to the general public and the international community as low.

The United States, however, has asked Russia to provide additional information about the circumstances of the incident and the test results, adding to concerns surrounding the case.

Plague is an acute bacterial infection caused by Yersinia pestis. Typical symptoms include sudden high fever, chills, headache, muscle pain, and severe weakness. Depending on the site of infection, the disease is generally classified as bubonic, septicemic, or pneumonic plague.

Diagnosis can be made by detecting Yersinia pestis in blood, lymph node aspirates, or respiratory specimens.

The incident in Russia has reignited investor interest in infectious-disease diagnostics, helping to drive buying across South Korean diagnostic stocks. However, industry officials say no domestic company is currently known to market a commercial plague diagnostic kit.

“As far as I know, no South Korean company has developed and commercialized a diagnostic kit specifically for plague,” an industry official said. “These stocks appear to be attracting attention simply because they are being grouped together as infectious-disease-related stocks.”

Pharmaceutical companies with antibiotics that can be used to treat plague also attracted investors.

Kukje Pharma hit its daily upper limit, closing at 4,430 won. The rally was linked to the company’s doxycycline product, Kukje Doxycycline Hyclate Hydrate Capsule 100 mg, as doxycycline is among the antibiotics used to treat plague.

Peptron Plummets as Lilly Evaluation Ends Without Commercial Deal

Peptron briefly hit the lower limit in after-hours trading on Tuesday before recovering slightly. It ended the session down 25.80% at 96,900 won.

The sell-off followed the company’s announcement that it had completed an extended technology evaluation of its SmartDepot long-acting drug delivery platform with global pharmaceutical company Eli Lilly, but had not reached the follow-on commercial agreement that investors had expected.

“Peptron’s technology evaluation period for the SmartDepot platform with Eli Lilly has ended,” the company said in a statement Tuesday. “We take seriously the fact that we were unable to announce a subsequent commercialization agreement at the end of the evaluation period.”

Peptron’s collaboration with Lilly began in October 2024, when the companies signed a platform technology evaluation agreement to test whether SmartDepot could be applied to peptide drugs owned by Lilly.

Under the agreement, Peptron granted Lilly a nonexclusive license for the evaluation, and the companies conducted joint research to assess the potential for developing long-acting formulations. The compounds being evaluated were not disclosed due to confidentiality provisions.

The evaluation period was initially described as about 14 months. However, in a revised regulatory filing in December 2025, Peptron changed the contract period to “approximately 14 months, up to a maximum of 24 months.”

During the evaluation period, Peptron also expanded its own commercialization efforts for SmartDepot.

The company filed a Phase 1 clinical trial application with South Korea’s Ministry of Food and Drug Safety for PT403, an obesity and diabetes candidate designed to deliver semaglutide once a month using the SmartDepot platform.

Peptron also received a decision granting a South Korean patent covering sustained-release formulation technology designed to release GLP-1 drugs, including semaglutide and tirzepatide, over an extended period.

The company has also committed significant capital to expanding its manufacturing capacity. Peptron is building a second plant in Osong, North Chungcheong Province, with an investment of approximately 90 billion won to manufacture long-acting drugs based on SmartDepot.

Despite these efforts to prepare the platform for commercialization, the lack of an immediate follow-on deal with Lilly has increased uncertainty for the company.

Peptron emphasized that the expiration of the evaluation agreement does not necessarily mean the two companies will end their business relationship.

“The completion of the joint research and evaluation procedures under the technology evaluation agreement does not mean that the possibility of future commercialization cooperation between the two companies has ended,” Peptron said, adding that it had received all payments stipulated under the agreement.

According to Peptron, the two companies plan to further review factors necessary for commercialization—including commercial feasibility, scalability for mass production, market potential, and intellectual property—based on the results generated through their joint research.

However, no decision has been made regarding whether the companies will proceed with further commercial cooperation, what form such an agreement might take, or when it could be signed.

“Whether follow-on commercialization cooperation will take place, as well as its specific structure and timing, will be determined through further review and decisions by both companies,” Peptron said. “At this point, it is difficult to provide specific details.”

The company added that it would continue working to convert the results accumulated through the joint research and technology evaluation into commercial value for the SmartDepot platform.

Hanmi Science Shares Surge Following Approval of In-House GLP-1 Obesity Drug

Hanmi Science also saw a sharp rise in after-hours trading, climbing 14.93% to 66,200 won.

The gain followed regulatory approval of a GLP-1 obesity drug developed by its pharmaceutical subsidiary, Hanmi Pharmaceutical.

South Korea’s Ministry of Food and Drug Safety announced Tuesday that it had approved Hanmi Pharmaceutical’s Efpe Autoinjector Injection in 2 mg, 4 mg, 6 mg, 8 mg, and 10 mg doses. The drug, whose active ingredient is efpeglenatide, was designated as South Korea’s 45th domestically developed new drug.

Efpe is an injectable treatment used as an adjunct to a reduced-calorie diet and increased physical activity for chronic weight management in adults with obesity or who are overweight but do not have diabetes.

The drug acts on glucagon-like peptide-1 (GLP-1) receptors in the central nervous system—including the hypothalamus and medulla—as well as in the gastrointestinal tract. It suppresses appetite and delays gastric emptying, helping patients feel full for longer.

GLP-1 is an incretin hormone naturally secreted by the intestine after food intake and plays a role in regulating blood glucose and appetite.

The Ministry of Food and Drug Safety stated that it reviewed Efpe under its new drug approval procedures, assigning a dedicated 19-member review team that included specialists in clinical trials, good clinical practice, and good manufacturing practice.

The regulator added that it also held customized face-to-face meetings with Hanmi Pharmaceutical during the review process prior to granting approval.

The approval is significant because Efpe is the first GLP-1 obesity treatment independently developed by a South Korean pharmaceutical company to reach the commercialization stage.

South Korea’s obesity drug market has so far been dominated by imported products such as Novo Nordisk’s Wegovy and Eli Lilly’s Mounjaro. Efpe’s entry could intensify competition in both pricing and supply.

Domestic manufacturing could also give Hanmi Pharmaceutical an advantage in terms of supply stability and cost competitiveness.

Efpe incorporates Hanmi Pharmaceutical’s proprietary LAPSCOVERY platform, meaning its approval also provides clinical and regulatory validation for the company’s long-acting drug technology.

“The approval of Efpe is particularly meaningful because it allows us to provide a stable supply of a treatment backed by clinical evidence reflecting the characteristics of Korean patients in a market that has largely relied on imported obesity medications,” said a Hanmi Pharmaceutical official.

"We will work to successfully establish the drug in the domestic market through rigorous quality control and a reasonable pricing structure, while contributing to improvements in patients’ health and quality of life."