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Battling Cancer

2016-05-14ByCuiXiaoqin

Beijing Review 2016年40期

By Cui Xiaoqin

Landing in Hong Kong after a three-hour flight from Beijing last November, Liu Ran rushed over to the Dr. Vio & Partners Hospital. It was her third visit in six months. Sitting in the waiting room, travel-weary Liu along with several friends, also from the Chinese mainland, were ready to receive their next human papillomavirus (HPV) vaccine. The virus has been found to be the main cause of cervical cancer.

Soon, however, young women on the Chinese mainland will not have to travel to Hong Kong anymore for the vaccine. British company GlaxoSmithKline (GSK) announced on July 18 that its HPV vaccine Cervarix has obtained marketing authorization from the China Food and Drug Administration, becoming the first approved HPV vaccine on the Chinese mainland. The vaccine, expected to reach the market early next year, will help prevent cervical cancer in young females aged 9 to 25.

A long wait

In 2006, Gardasil, the worlds first HPV vaccine produced by Merck Sharp & Dohme (MSD), was approved by the U.S. Government. Since then Gardasil has been used in more than 100 countries and regions around the world.

But on the Chinese mainland, the HPV vaccine rollout was delayed because of lengthy clinical trials. “Some of my colleagues started to pay attention to HPV vaccines some time ago. Many of them chose to go to Hong Kong for it because they didnt see any possibility that it would be available on the mainland soon,” Liu said, “As far as I know, the optimum age for receiving the HPV vaccine is before 25. Im 26, so I dont have time to wait. I need to safeguard my health as soon as possible.”

Dr. Wang Shaoming, with the Institute of Oncology of Peking Union Medical College, wrote in a paper published in the international academic journal Vaccine that if the HPV vaccine was given to females aged 9 to 15, the seven-year gap between 2006 and 2012 would mean 59 million Chinese females lost their best chance of access to the vaccine. Among them, 380,000 would likely get cervical cancer and 210,000 would die from the disease if no intervention measure like regular screening is taken.

So why did it take so long for the Chinese mainland to approve the HPV vaccine? One important reason is that it has a different drug approval system. Under the Chinese law of drug registration, clinical trials designed for Chinese people are obligatory before a foreign pharmaceutical company can get approval for a new drug.

According to Chinas management procedures for imported drugs, an imported vaccine should undergo domestic clinical trials before it can hit the market. But as it takes much longer for vaccines than other drugs to show effects, GSKs Cervarix, for example, spent six years in a clinical trial involving more than 6,000 subjects.

Mass demand

According to a report released by CA, a cancer journal for clinicians, China showed a rising trend of cancer morbidity and mortality in 2015. Cervical cancer was among the top 10 diseases in terms of morbidity.

According to the World Health Organization, cervical cancer is the second most common cancer among women in developing countries. There are around 130,000 new cases every year in China, more than 28 percent of the worlds total. The disease also has the highest mortality rate worldwide.

“Cervical cancer is currently the only malignant tumor with a definite etiology. It can be gradually eliminated by measures such as HPV vaccines, regular screening and early detection and treatment,” said Lang Jinghe, Director of Obstetrics and Gynecology, Peking Union Medical College Hospital, at a conference held in 2014.

But the HPV vaccine does not mean 100 percent prevention, because the vaccines currently available in the market do not target all the carcinogenic virus subtypes, said Professor Zhou Qi from Chongqing Cancer Hospital. Regular screening is still necessary even after one receives the vaccine, he said.

Remaining doubts

“I did a lot of research online to learn about the vaccines safety and necessity,” said Liu. “Before the final decision was made, I hesitated a lot.”

Her initial trepidation was not unfounded, as the HPV vaccine can cause adverse reactions such as pain, swelling, redness, fever, dizziness, and nausea. Some also worry that a history of 10 years is too short to prove its safety.

One well-known case of reaction occurred in 2013, when more than 30 Japanese women experienced body pain after receiving the GSK vaccine. As the pain didnt subside even after treatment, the Japanese Government suspended its recommendation of the two HPV vaccines, but did not ban the vaccines outright.

“There is no evidence so far of a causal link between the vaccine and these serious adverse reactions,” said Gong Xiaoming, Doctor at Shanghai First Maternity and Infant Hospital. “It might have been accidental.”

Liu said she had been reading about the adverse reactions right before she left for Hong Kong the first time. “I was a little scared,” she admitted. “But I eventually went, because I did not want to waste the money I had paid.”

As of March 2014, a total of 170 million doses of HPV vaccines had been administered globally. Besides the safety issue, the expensive price is another concern. Each dose of the HPV vaccine costs 850 yuan($128) and a course consists of three shots. In many places, the vaccines are provided to young girls at the optimum age for free.

“I got a discount thanks to a cooperation project between my company and the hospital, but the three shots still cost me $290. And I spent even more on flight tickets and hotels,”said Liu. “Thats the reason why some people gave it up, especially those above 25—limited efficacy and huge cost.”