South Korean shares ended lower Friday, snapping a two-day winning streak, as investors remain concerned about progress in the development of drugs to treat COVID-19 despite rebounding oil prices. The Korean won fell against the US dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) fell 25.72 points, or 1.34 percent, to 1,889.01. Trading volume was moderate at 922 million shares worth 9.5 trillion won ($7.7 billion), with losers far outpacing gainers 684 to 165.

The main index got off to a weak start and extended losses in the afternoon trading on reports that Gilead Sciences Inc.'s antiviral drug remdesivir failed to help seriously ill COVID-19 patients in its first clinical trial, analysts said.

They expected the KOSPI may trade in a tight range next week amid lingering concerns over the COVID-19 outbreak and its economic impact.

"The index's gains will be limited as investors will continue to assess the COVID-19 pandemic's impact on the global economy and corporate profitability to take a cue for asset readjustment," Ha In-hwan, an analyst at Meritz Securities Co., said.

Institutions and foreigners sold a combined 654 billion won worth of stocks, offsetting individuals' stock purchases valued at 633 billion won.

Most large-cap stocks retreated.

Market bellwether Samsung Electronics Co. fell 1 percent to 49,350 won, top carmaker Hyundai Motor Co. declined 2.5 percent to 90,100 won, and the state-run Korea Electric Power Corp. shed 2.8 percent to 22,550 won.

Among gainers, leading steelmaker POSCO rose 0.9 percent to 173,000 won and Hanjin KAL Corp., parent firm of national flag carrier Korean Air Lines Co., jumped 9.2 percent to 93,000 won.

The local currency closed at 1,235.50 won against the US dollar, down 5.80 won from the previous session's close.

Bond prices, which move inversely to yields, closed higher. The yield on three-year Treasurys fell 1.8 basis points to 1.018 percent, but the return on the benchmark five-year government bond declined 1.4 basis points to 1.277 percent. (Yonhap)