Hong Kong stocks started Tuesday's session on a weak note, with the benchmark Hang Seng Index shedding 0.19% to open at 25,280.82 points. The Hang Seng Tech Index fell 0.41% to 4,532.22 points, while the Hang Seng China Enterprises Index dropped 0.18% to 8,447.25 points. Pre-market turnover reached approximately HK$8.238 billion.

Pharmaceutical stocks led gains, with SIMCERE PHARMA (02096) surging nearly 5%, Everest Medicines (01952) climbing about 5%, and Consun Pharmaceutical (01681) advancing more than 3%. In corporate news, SIMCERE PHARMA announced a global development and commercialization licensing agreement with Roche for the trispecific antibody SIM0660, with a potential total transaction value exceeding US$1.53 billion.

Data center related stocks also attracted attention, as SUNeVision Holdings (01686) rose nearly 7%. Conversely, gold mining counters experienced broad declines, with Shandong Gold Mining (01787) sliding nearly 5%, while Lingbao Gold (03330) and Zijin Gold International (02259) both dropped over 4%.

Property management and construction stocks also came under pressure, with Onewo Inc (02602) losing nearly 7% and Zhiyun Technology Construction (09900) retreating more than 5%.

The cautious opening followed overnight losses on Wall Street, where the Dow Jones Industrial Average fell 0.79%, the S&P 500 declined 0.71%, and the Nasdaq Composite dropped 1.03%. The Philadelphia Semiconductor Index slid more than 2%. Additionally, spot gold tumbled 2.48% to US$4,327.28 per ounce, breaching the US$4,400 support level. Heightened risk aversion driven by escalating US-Iran tensions, combined with the sharp overnight drop in bullion prices, contributed to the broadly weaker start for Hong Kong equities.