解放军文职招聘考试案例8：HIV新疫苗试验

 案例8：HIV新疫苗试验
Case 8: Testing a New HIV Vaccine

Viravax是一家英国公司，生产了一种很有希望的抗HIV疫苗。动物实验很成功，I、II期临床试验表明疫苗非常安全，并在所有志愿者中都产生了明显抗体。公司希望在越南进行III期临床试验，该国以往的筛查曾检出一组HIV-I阳性的静脉吸毒者，而该疫苗就是针对该人群的HIV病毒株的。Viravax公司答应免费供应疫苗，还将负担试验所需费用，提供所有必需的实验设备、计算机、现场工作需要的车辆等。公司还同意，如果疫苗证明有效，将免费提供给该城市的静脉吸毒者，并有价地提供给农村，为期5年。
讨论主要涉及如何处理HIV阳性反应(HIV+)的病人。试验分两组，采用随机双盲法，一组接受疫苗，一组接受安慰剂。所有受试者均测HIV抗体，阳性者给予政府规定的“标准治疗”，但不给予抗逆转录病毒药物或蛋白酶抑制剂。
知情同意分两步进行。先是向可能的受试者介绍研究项目情况，包括疫苗的实验性质和处理原则。两天后，对他们进行口头或书面测验，看他们对研究性质和自己的权利是否完全理解。只有通过测验的人才被征募为受试者。研究方案呈送给单位的伦理审查委员会和一个为公司或私人单位的研究方案进行伦理审查的事务所进行审查。在越南卫生部的要求下，还送到UNAIDS进行了非正式审查和评议。卫生部的疫苗分委员会批准了该研究方案并呈送卫生部伦理委员会。各级审查委员会都批准了这个项目。
在研究开始后，艾滋病活动分子团体发表一篇文章对该试验进行了谴责。他们批评该试验没有对HIV+的病人提供最新治疗。他们认为在越南做本研究的唯一理由就是要便宜得多，因为越南不要求用昂贵的三联抗HIV治疗作为对照干预，而在英国是必需使用的。他们认为这样的研究方案在英国是根本不可能被政府或大学的伦理审查委员会批准的。Viravax公司则反驳说，使用最新治疗本身就是不合伦理的，因为它在越南不可能持久，只有一小部分人能得到它；而且，越南的医生对这种治疗及其副作用不熟悉；此外，给予世界上最好的治疗有诱导参与的性质，实质上是胁迫受试者接受疫苗的一种形式。

问题：

1.本研究没有给予HIV+病人世界上最佳的可得治疗，它是否因此而不合乎伦理？
2.如果公司给了HIV+病人世界上的最佳可得治疗，但这种治疗在越南是得不到的，而且在最近的将来除了非常富有的人以外普通百姓也不可能得到，那么给予最佳治疗是否不合乎伦理？
3.有没有双方都可以接受的折中方案？
4.如果疫苗的研发者是一个越南公司，它愿意在本国进行疫苗试验，则对于应该给HIV+病人以“最佳可得治疗”或“当地的标准治疗”在看法上会不会不同？在这个问题上的相同标准或不同标准各有什么含义？
5.如果疫苗的推广使用是东道国所负担不起的，那么还应该在该国进行疫苗试验吗？
6.对于该国的吸毒群体还应该提供哪些服务？

 

Case 8: Testing a New HIV Vaccine

Viravax, a UK-based company has developed a vaccine against HIV that appears promising.  Animal studies were very successful and phase I and phase II trials demonstrated that the vaccine was remarkably safe and that it produced significant antibody levels in essentially all of the volunteers.  The company now wishes to begin phase III trials in Ho Chi Minh City, Vietnam where previous surveillance has identified a cohort of intravenous drug users (IDU) with a high rate of conversion to HIV-1.  Such a study could be completed in two years. The Vietnamese Government has expressed interest in having the study conducted in their country and begins negotiations with Viravax.  The vaccine, which is specifically directed against the strain that predominates in the Vietnamese IDU population, will be provided free by Viravax.  Viravax will also cover the cost of conducting the study, which will be carried out by the Vietnam Vaccine Institute.  In addition to the study costs, the company will provide all of the laboratory equipment necessary to conduct the studies, ten computers for the Institute, and two vehicles to visit the study sites. The company agrees that if the vaccine proves effective it will be given free of charge to the IDU population of the city and at cost to the country for five years.

This will be a randomized double blind prospective study with one group receiving the test vaccine and the other group receiving a placebo.  All potential participants will be tested for HIV prior to being enrolled in the study, and if they are HIV+ they will be referred to one of the municipal hospitals of the Ho Chi Minh City Corporation.  The company and the Institute also agree that anyone who converts to HIV+ during the study will be referred to one of the Municipal Corporation hospitals to be treated by the standard method published in the Ministry of Public Health document, "Guidelines for the Clinical Management of HIV Infection in Children and Adults.”  This means that all infections are treated but patients are not given anti-retroviral drugs, including AZT, or protease inhibitors.  If there are any changes to the standard therapy recommended by the government, all previous (and future seroconvertors) will be switched to the new therapy.  The Municipal Corporation will provide treatment for the lifetime of the seroconverted participants.  Individuals can drop out at any time without fear of prejudice.

The informed consent process will have two stages.  First, potential participants will be briefed about the study, including an explanation of the experimental nature of the vaccine and the treatment policy. Two days following the initial briefing the individuals will return to the Institute where they are given a brief oral and written exam to see if they fully understand the study and their rights.  They will only be enrolled if they pass the test. The study is submitted to the Ethical Review Board of the Institute and to a firm that conducts ethical reviews for companies in the private sector who wish to conduct research on human subjects. The protocol is also reviewed informally and commented on by UNAIDS at the request of the Ministry of Public Health Technical Subcommittee on HIV Vaccines. The Subcommittee approves the protocol and forwards it to the Ministry of Public Health Ethical Committee. All review boards approve the study.

After the study has begun, an article condemning the study appears in an AIDS activist group’s publication.  The group objects to the fact that the study does not provide state-of-the-art care for seroconverting individuals.  They argue that the only reason the study is being conducted in

Vietnam is because it is much less expensive to do there, as triple therapy is not required (which would be necessary if the study was conducted in the UK).  They feel that the study (as presently designed) would never be approved by a UK government committee or a university ethical review committee in the UK.  Viravax counters that the use of state-of-the-art therapy would in itself be unethical because the treatment regimen would not be sustainable in Vietnam and only one small group would have access to this therapy.  In addition, the physicians in Vietnam would be unfamiliar with the therapy and unaware of all the possible side effects.  And lastly, by offering the best care available in the world, the study would be giving an unfair inducement to participate. 

Questions
1.Is the study unethical because participants are not being offered the best care available in the world if they should become HIV+?

2.Would it be unethical to offer state-of-the-art care to seroconvertors even if the care was not available in Vietnam, and was unlikely to be available within the near future except to the very wealthy? 

3.Is there any compromise position that may be acceptable to both parties?

4.If the developer of the vaccine was a Vietnamese company who wished to conduct the study in its own country, would the use of "best available or standard local therapy" for seroconvertors be viewed differently? What are the implications if the standards are different? The same? 

5.Should the vaccine be tested if it is presently unaffordable to the country for wide distribution?

6.Are there any other services that should be provided to the IDU population?