A landmark High Court decision has for the first time allowed the use of a controversial but widely successful HIV prevention drug for use on the NHS. Truvada®, a combination of highly active antiviral drugs tenofovir and emtricitabine, shows up to a 92% reduction in the risk of transmission if used correctly. The pill, if used daily and under regular physician review, is claimed to be highly successful. However, due to its high cost, and the availability of other and potentially more cost-cutting measures, it may still be a long time before this drug is readily available, if at all.
HIV is a blood-borne retrovirus thought to have mutated from a simian form, transmitted to humans through the consumption of blood products. Transmission is through blood, and highest rates are through anal sex, but the highest burden is now within straight couples. The virus attacks human immune cells, often hiding under the radar for up to a decade or more before doing enough damage to cause symptoms. The lack of working immune cells leads to infection with common bacteria which can be fatal, a clinical syndrome known as Acquired Immunodeficiency Syndrome. Treatment is by a cocktail of aggressive antiviral drugs, which has now boosted life expectancy to normal levels.
Prevention of disease transmission has classically been to avoid blood or transmission routes. The use of physical prophylaxis, such as condoms, has been widely successful but not without failure. The use of a medical treatment, such as Truvada®, provides a chemical barrier to infection, acting as a safeguard to any stray virus and stopping it in its tracks. Designed for use in long-term relationships in couples where one is positive, it reduces the risk of transmission very well if used properly.
The danger of using such drugs is with human error. Although having a 92% success rate, there have been failures. Explanations range from poor use, to individual resistance to drug efficacy. It is recommended that the drug be taken daily, with regular physician follow-up to ensure correct drug adherence and early identification of risk. The other issue is cost, with a projected charge of up to 20 million pounds yearly. This may not be something a cash-strapped NHS can afford, even when compared to the cost savings of not having to treat more HIV infections.
The availability of relatively effective and cheap barrier methods, when used alongside public health interventions and safe-sex media campaigns, means that using Truvada® may not be cost-effective. It may be that safe sex using current measures is enough, with Truvada® reserved for high-risk candidates or for use in specific situations. There is also a danger that Truvada® will be misused as a ‘complete fix’, where people not using barrier methods may contract other disease. Another danger is the emergence of HIV drug resistance strains, where barrier methods are of even more vital importance.
Although the recent court ruling is claimed as a victory, we must consider the pragmatic elements of such a ‘wonder pill’. If used correctly, and if cost can be reduced, Truvada® may work as either a primary or back-up safeguard against HIV in high-risk populations. Any use would have to be alongside barrier methods and under physician review to ensure compliance. Truvada® may not be the miracle we have all been waiting for, but it certainly has its merits. But until cost drops and efficacy works beyond conventional measures, widespread use may just be a pipedream.
Any opinions above are the author's alone. Guidance is based the best available evidence at the time of writing All data are based on externally validated studies unless expressed otherwise. Novel data are representative of sample surveyed. Online recommendation is no substitute for seeing your own doctor and should not be taken as medical advice. Review any new exercise or diet regime with your primary healthcare provider
Dr Ben Janaway MBChB is a young NHS doctor in the Southwest. His interests include neurology, health communication, and medical ethics. He is also an avid advocate of compassionate care and quality improvement, running a project in the Southwest around medical humanities. Please follow and support: Dr Janaway on Facebook Dr Janaway on Twitter
Sources and further reading
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