化学世界（Chemistry World）：疫苗开拓者尹卫东

Chemistry World March 2008 Vol 5, No 3

　　当北京科兴生物制品有限公司总经理尹卫东在1992年建立公司研制一种甲型肝炎疫苗的时候，从事疫苗研发的他甚至连“生物技术”这个术语都未曾听说过。
现在，15年过去了，尹卫东成为中国迅速增长的生物技术产业的重要人物之一，北京科兴成为第一家在美国上市的中国生物技术公司。 
但是这段经历对尹卫东来说并不容易。一切都始于1990年，尹卫东完成中国疾病预防控制中心病毒病预防控制所的进修后不久。当时，作为在中国东部城市唐山工作的一名医生，他正在从事研究。
在一次到学校给孩子们注射甲肝疫苗针的时候，他携带了两种疫苗，一种是中国造的减毒活疫苗，比较便宜，一种是制药巨头葛兰素公司（Glaxo）生产的灭活疫苗。一剂葛兰素的疫苗价格要超过300元人民币，相当于当时普通中国人一个月的工资，高于中国疫苗价格的10倍以上。
但是没想到的是，尹卫东发现大多数父母仍然给孩子选择进口疫苗。他回忆道：“在感受到中西方科技水平的巨大差距时，我也意识到好疫苗的巨大市场潜力，即使这些好疫苗并未被纳入国家计划免疫项目中。”
1992年初，他决定放弃从医，在唐山市和当地疾病控制中心合作开办了一家小公司。尹卫东告诉记者说：“尽管我们渴望研发中国自己的高质量疫苗，我们必须首先加强自己的实力。”

艰难岁月

　　当初那家在唐山市建立的公司现在是Sinovac的子公司，它不仅生产肝炎诊断试剂还销售药品和医疗设备，不过公司的所有利润都被用于支持疫苗研究。尹卫东说：“那是段艰苦岁月，我们的钱包经常是空的。”
1999年底，甲型肝炎灭活疫苗终于通过中国国家食品药品监督管理局审批。这个许可证帮助尹卫东吸引到足够的资金来创办北京科兴。
疫苗生产车间方案本来已经按照中国标准拟订好了，但当尹卫东将方案送给一家意大利设计公司时，方案被完全否定。意大利厂商提出的替代方案要花费原设计方案5倍以上的资金。这是个重大的打击。以更高规格建立车间意味着用尽公司当时筹集的所有资金，使公司面临巨大的金融风险。
尹卫东回忆道：“我们度过了很多不眠之夜，但是最终，我们决定放弃原来方案，接受新的设计。” 公司生存了下来。科兴生物肝炎疫苗的销售量剧增，公司启动了其它疫苗开发项目。
采用意大利设计被证实是一个有远见的决定。2003年之前，还没有中国制药公司在美国上市。但是2004年年中，科兴生物在美国证券交易所正式挂牌交易，其赢得投资者支持的部分原因是车间生产的高标准。

抗击非典和H5N1型禽流感病毒

　　当科兴生物正在争取海外上市时，非典（严重急性呼吸道症候群）正迅速横扫中国。不顾危险，不计花费，科兴决定集中精力研究非典疫苗。
2003年11月，非典爆发得到控制的4个月之后，科兴生物研发的世界第一个非典疫苗的第一阶段临床试验通过了国家食品药品监督管理局的正式批准。仅仅两年后，科兴生物成为中国第一家研制出致命的H5N1型禽流感病毒疫苗的公司。
尽管这两个疫苗的大多数研究开发费用由中国政府承担，科兴生物必须勇敢地面对无法补偿公司项目投资的可能性，除非两种疾病进一步爆发。
由于这两种疾病没有另一次大流行的征兆，公司最近决定延缓其非典疫苗项目，尽管第一阶段临床试验已卓有成果。
但虽然如此，尹卫东相信将钱投入研发这两种疫苗是非常值得的。“当我们为抗击公共卫生危机而奉献时，北京科兴已经发展了一种研究开发能力，使我们在商业机会刚出现时就能迅速抓住它们，”他说，“这比任何短期收益率都要重要得多。”

[英文] Profile: Vaccine trailblazer[原文网址]

When Yin Weidong, general manager of the vaccine developer Sinovac Biotech, established his company to develop a hepatitis A vaccine in 1992, he hadn't even heard the term 'biotech'.

Now, 15 years on, Yin is one of the leading lights of China's fast growing biotech industry and Sinovac the first Chinese biotech firm listed on the US stock exchange. 

But it has not been an easy road for Yin. It all began in 1990, shortly after he finished studying at the Chinese Centre for Disease Control and Prevention's Beijing-based Institute for Viral Disease Control and Prevention. At the time, Yin was undertaking research while working as a doctor in Tangshan, a city in the east of China.

Visiting primary schools to administer Hepatitis A shots to children, Yin brought with him two versions of the vaccine - a cheap live attenuated vaccine made in China, and an inactivated vaccine made by pharmaceutical giant Glaxo. At over 300 yuan per dose, Glaxo's vaccine was the equivalent of a month's salary for the average Chinese worker and 10 times more expensive than the Chinese vaccine. But unexpectedly, Yin found that most parents still chose to pay for the imported vaccine.

'While feeling how big the gap was between China and the West, I also sensed the strong market potential of good vaccines, even if they are not covered by public vaccination programmes,' recalls Yin.

In early 1992, he decided to give up practising medicine and started a small company in Tangshan, in partnership with the local disease control centre.

'Although we were eager to develop China's own high-quality vaccine, we had to build ourselves up first,' Yin told Chemistry World.

Difficult years
The Tangshan company, now a subsidiary of Sinovac, produced a hepatitis diagnosis reagent as well as selling drugs and medical equipment. But any profits were used to fund vaccine research. 'Those years were difficult and our wallets were often empty,' says Yin.

In late 1999, the inactivated hepatitis A vaccine was finally approved by China's State Food and Drug Administration (SFDA). The license helped Yin attract the investment he needed to launch Sinovac.

But there was still trouble ahead. Plans for a vaccine production plant were drawn up in line with Chinese standards.
But when Yin showed it to the Italian firm charged with designing the plant, they rejected it outright. Instead, they put forward a design that would cost five times more to build than the original. It was a huge blow. Building the plant to the higher specifications would mean using up all the money the company had raised so far - an enormous financial risk.

We had many sleepless nights,' Yin recalls. 'But eventually we decided to give up on the original and accept the new design.'

The company survived. Sales of Sinovac's hepatitis vaccine soared and the company had other vaccines in its pipeline.

And going with the Italian design turned out to be far-sighted decision.

Before 2003, no Chinese pharmaceutical company had floated on the US stock exchange. But in the middle of 2004, Sinovac was formally listed - winning the backing of investors thanks in part to the high production standards of its plant.

Fighting SARS and H5N1
As Sinovac got its overseas listing, SARS (severe acute respiratory syndrome) was sweeping rapidly across China. Despite the risk and expense, the firm decided to concentrate on developing a SARS vaccine.
In November 2003, four months after the outbreak was contained, Sinovac won SFDA approval for phase I clinical trial of the world's first SARS vaccine. Just two years later, it became the first company in China to develop a vaccine against the deadly H5N1 virus.

Although much of the R&D costs of the two vaccines were borne by the Chinese government, Sinovac has had to face up to the possibility that it may not recoup its own investment in either project unless there are further outbreaks of the two diseases.

With no sign of another epidemic, the company has recently decided to suspend its SARS vaccine programme despite successful results from its phase I trial.

But nonetheless, Yin believes ploughing their money into the vaccines has been worthwhile. 'While devoting ourselves to fighting public health risks, Sinovac has developed an R&D capacity that allows us to quickly grasp business opportunities as they emerge,' said Yin. 'This is much more important than any short-term profitability.'