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This article outlines likely complexities for researchers and research ethics committees, including …


Biology Articles » Bioethics » Enrolling adolescents in HIV vaccine trials: reflections on legal complexities from South Africa » Background

Background
- Enrolling adolescents in HIV vaccine trials: reflections on legal complexities from South Africa

Adolescents have been involved in trials for vaccines to prevent sexually transmitted infections/diseases like Human Papilloma Virus (HPV) and Herpes Simplex Virus type-2, (HSV-2), both in the developed and the developing world [1,2]. In Merck's ongoing quadrivalent HPV vaccine program, at least 12 000 young people between the ages of 9–24 have received the HPV vaccine, with approximately 20% of these being boys and girl between the ages of 9–15 (Merck, personal communication). Infants have also participated in phase I HIV vaccine trials and currently Uganda is enrolling HIV exposed infants in a phase I vaccine trial [3,4]. However, no HIV uninfected adolescents have participated in HIV vaccine trials anywhere in the world.

Because adolescents are severely affected by the HIV epidemic [5-7], they should be the main recipients/beneficiaries of a successful HIV vaccine. To achieve this, there will be a need to license the vaccine for use in this age group. Adolescent participation in HIV vaccine trials is therefore paramount in order to determine the safety profile, appropriate dosing schedules and the degree of immunogenicity in this age group. Adolescent trials are also necessary as vaccine responses may differ because of physiological or hormonal differences between adults and younger adolescents [8,9]. Delays in licensure for use in adolescents could retard the control of the HIV epidemic, as was seen in the control of the Hepatitis B epidemic in the United States where there was no clear strategy to include infants, children and adolescents in the vaccination program [10].

South African researchers anticipate enrolling 16–18 year olds in a phase IIb proof of concept vaccine trial towards the end of 2007. These adolescents will be at high risk of HIV infection. Further, it is envisaged that 12–15 year old adolescents will be involved in phase I/II trials as early as 2008. The phase I/II studies will determine the safety, tolerability and preliminary immunogenicity in pre-teens and young adolescents of candidate vaccines that are currently being tested for preliminary efficacy in adults and older adolescents. The phase I/II studies will involve a small number of healthy adolescents, at low risk of acquiring HIV infection.

In the development and review of adolescent HIV vaccine protocols, there are many legal complexities that need to be addressed. This article sets out complexities linked to consent requirements; special legal protections for children in need of care and protection; and procedural requirements for the approval of such research. These complexities are not unique to South Africa because in many jurisdictions where such trials may occur adolescent participants will have limited legal capacity, and the enrolment of adolescents must take account of local laws dealing with, for e.g., the age of lawful consent to sex and obligations on certain adults to report abuse. Furthermore, like South Africa, very few developing countries will have dedicated research laws. Therefore this article also discusses implications of these legal complexities for role-players in other jurisdictions. We make a series of recommendations for additional work that needs to be done in order to realize the optimal involvement of adolescent participants. We refer to "child" as a person under the age of 18 [11,12] and a "minor" as a person under the age of 21 [13] soon to change to 18 [14]. We use the term "adolescent" to refer to persons between the ages 12 and 18 [15].

HIV vaccine trials

Phase I/II HIV vaccine trials with adolescents would aim to recruit a small number of healthy adolescents who are at low risk of acquiring HIV infection. Phase IIb trials will recruit adolescents at higher risk of HIV infection. The trials themselves will comprise of a number of interventions, including a general physical examination and medical history-taking; assessment of HIV risk factors including personal questions about sex and substance use; personalized risk reduction counseling; administration of an experimental HIV vaccine or placebo via injection; blood draws for laboratory safety and immunogenicity testing; and regular testing for HIV infection. Adolescents will be classified as "low risk" if they are not sexually active as defined as primary abstinence (no sexual activity ever initiated) or secondary abstinence (no sexual activity for six months). Although many interventions in a phase I trial may not hold out the prospect of direct benefit for adolescent participants, there are interventions that may benefit participants, such as personalised risk reduction counselling. Additionally, there may be associated benefits such as identification of medical conditions like hypertension and early referral to care, access to care for intercurrent illness or reproductive health, and referral for abuse. Despite conceptual difficulties in classifying whole protocols as either "therapeutic" or "non-therapeutic research" [16] it is possible that phase I safety trials in South Africa would be classified as "non-therapeutic" because of the preponderance of interventions that will not confer direct benefit.


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