Hong Kong stocks rallied for a fourth straight week as the final presidential debate wrapped up in the US and ahead of a major political event in China where policymakers will decide the country's economic blueprint for the next five years.

The Hang Seng Index advanced 0.5 per cent to 24,918.78 on Friday, up 2.2 per cent this week.

On the mainland, major benchmarks closed lower after marginal gains earlier in the day, as investors turned cautious ahead of China's Fifth Plenum of the 19th Communist Party Congress next week.

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The CSI300 Index, which tracks the biggest companies in Shanghai and Shenzhen, lost 1.3 per cent to 4,718.49. It ended the week 1.5 per cent lower, snapping a three-week rally. The Shanghai Composite Index edged down 1 per cent to 3,278, translating to a 1.8 per cent decline for the whole week.

In Hong Kong, oil companies led the gains after Russian President Vladimir Putin said the nation does not see a need to alter the existing deal between major global oil producers to cut output amid slumping demand brought about by Covid-19. Sinopec and CNOOC advanced more than 7 per cent, and PetroChina climbed 6.9 per cent,

"The market is still optimistic about the short-term outlook, although [traders] are still concerned about uncertainties around the US stimulus package and presidential election," said Castor Pang, head of research at investment services firm Core Pacific-Yamaichi. "There are some large IPOs coming, investors believe the market has not reached its peak."

Health care stocks were the biggest losers after a volunteer taking part in a clinical trial of the Covid-19 vaccine developed by AstraZeneca died in Brazil according to an announcement by local authorities on Wednesday. The first death reported in worldwide vaccine trials weighed on market sentiment, despite the fact the volunteer was reportedly in the control group and had therefore not received the vaccine.

CSPC Pharmaceutical Group shed 3.1 per cent. WuXi Biologics declined by 2.5 per cent.

On the mainland, health care stocks bore the brunt of the losses. Shenzhen Kangtai Biological Products dropped 7.1 per cent and Shanghai Fosun Pharmaceutical Group fell 5.4 per cent.

Donglai Coating Technology Shanghai surged by 123.4 per cent on its trading debut, while fellow debutant Canggang Railway closed flat in Hong Kong.

Mobile payments giant Ant Group, an affiliate company of Alibaba Group, has been a hot topic among traders, as its dual listings in Hong Kong and Shanghai are approaching. It was valued roughly between US$350 billion and US$450 billion as it kicked off its digital IPO roadshow in Asia, Europe and the United States this week.

Alibaba, which also owns the South China Morning Post, lost 0.7 per cent to finish Friday at HK$298. It failed to sustain the HK$300 mark that it broke for the first time earlier this week.

Elsewhere, stocks on Wall Street climbed as economic data improved in the US.

The number of Americans applying for jobless claims dropped to 787,000 last week, according to the Labor Department. And sales of secondary homes rose to a new 14-year high in September, the National Association of Realtors said, according to The Wall Street Journal.

US lawmakers' talks on a stimulus package to relieve the impact of the coronavirus pandemic are still ongoing, although a deal before November 3, the presidential election day, is seen as increasingly unlikely.

This article originally appeared in the South China Morning Post (SCMP), the most authoritative voice reporting on China and Asia for more than a century. For more SCMP stories, please explore the SCMP app or visit the SCMP's Facebook and Twitter pages. Copyright © 2020 South China Morning Post Publishers Ltd. All rights reserved.

Copyright (c) 2020. South China Morning Post Publishers Ltd. All rights reserved.