Alteogen (196170), the KOSDAQ's largest company by market capitalization, closed lower on the 19th ahead of the weekend.

According to Naver Pay Securities, Alteogen finished trading at 353,500 won, down 16,000 won (-4.33%) from the previous trading day. Based on the NXT closing price, it recorded 351,500 won, down 18,000 won (-4.87%).

Alteogen opened the day at 370,500 won and attempted a rally, rising to as high as 378,500 won during the session, but failed to sustain the upward momentum. Selling pressure subsequently expanded, pushing the stock down to 345,000 won intraday before ultimately closing in the 350,000-won range.

As a leading large-cap biotech stock representing the KOSDAQ market, Alteogen's price trajectory is closely tied to the index's direction, drawing keen attention from investors.

Indeed, the KOSDAQ market exhibited significant volatility on the same day. The KOSDAQ index rose to 1,001.40 during the session, breaching the 1,000 mark, but later gave up its gains and turned lower. The index, which had been pushed down to as low as 946.15 intraday, recovered some of its losses to close at 966.59.

Alteogen, a flagship KOSDAQ stock, also rose to the 370,000-won level early in the session before reversing lower in tandem with the index's weakness. Market participants are closely watching whether Alteogen, the top-ranked KOSDAQ stock by market capitalization, will be able to stage a rebound amid next week's market sentiment.

[※ Investment decisions are the sole responsibility of the investor, and the information contained in this article is subject to change depending on market conditions.]