Hong Kong's stock market opened with a positive tone on August 4, as the Hang Seng Index climbed 0.31% to 26,090.98 points, while the Hang Seng Tech Index rose 0.30% to 4,890.34 points.

The pharmaceutical CXO sector saw a significant surge, with WUXI APPTEC (02359) jumping nearly 10% after posting strong half-year results. The company reported revenue of 288.97 billion yuan in the first half, a 38.93% increase year-on-year, and raised its full-year performance guidance across the board. Other sector players also advanced, with WUXI BIO (02269) gaining over 3%, JOINN (06127) rising nearly 6%, ASYMCHEM (06821) climbing more than 5%, and TIGERMED (03347) adding nearly 4%.

The optical communication sector was active, with ZJ INNOLIGHT (03308) surging more than 9%. Cloud computing and AI application stocks also moved higher, as Kingsoft Cloud (03896) rose over 5%.

Most technology stocks traded in positive territory, with Alibaba-W (09988), Baidu Group-SW (09888), and JD Health (06618) each gaining more than 1%.

The upbeat opening was driven by strong performance in US tech stocks overnight, as the Nasdaq Composite Index jumped 2.13% and the Philadelphia Semiconductor Index advanced 1.05%.