Re: Re: H2O toxicity 7 July 2003
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Peter J Flegg,
Consultant Infectious Disease Physician
Blackpool Victoria Hospital, UK, FY3 8NR

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Re: Re: Re: H2O toxicity

Any fool can sit at a computer keyboard and pull out hundreds of references to toxicity associated with HIV therapies. However, it is quite another matter to use one's experience to place the advantages and disadvantages of therapy into its proper clinical context.

Let me introduce both Chris Tyler and Carl Williams to a novel concept - that of risk-benefit analysis. For antiretroviral therapy, the balance of the equation is clearly and unambiguously weighted in favour of therapy (assuming it is prescribed according to the current national guidelines).

I am fully aware of the fact that the drugs have toxicities - that is undisputed. What is also undisputed is the fact that that since the widespread introduction of these "lethal" and "AIDS-causing" drugs in the West (a seven-fold sales increase between 1995 and 2000), both the death rate and progression rate to AIDS have plummeted. It is facts like these which contribute to the broad consensus and acceptance that HIV therapy is clearly beneficial.

I don't intend to get into a "point by point" rebuttal match over the references cited by Chris Tyler and Carl Tyler. Bitter experience (see the debate with David Rasnick http://bmj.com/cgi/content/full/326/7381/126/e#responses) tells us this leads nowhere fast. However I would like to highlight some misunderstandings that evidently still persist to this day, 15 years after the drugs were first licensed.

Firstly, zidovudine doses were up to three times higher in the late 1980s than are currently used now, and side effects (usually reversible on discontinuation or dose reduction) occurred at far higher frequencies than are seen today. Speculation 15 years ago about the scale of future toxicity is merely speculation, a fact true even then. Toxicities such as reversible/transfusion dependent anaemia affect only about 5% of recipients of current regimens. Sick people with AIDS get anaemia but this is usually multifactorial and seldom due to zidovudine alone.

Secondly, pointing out that individuals who have died from AIDS are more likely to have had treatment with zidovudine than those who remain healthy is tantamount to saying patients who have died from cancer are more likely to have had chemotherapy than patients who are well enough not to require chemotherapy. Remember that HIV therapy is reserved for symptomatic patients (these are by definition more advanced, and therefore more likely to die).

I am called to task by Carl Williams, who thinks my death by drowning analogy is "frankly offensive". Yet he accepts uncritically Chris Tyler's descriptions of zidovudine as a drug "responsible for the agonizing death of many thousands", and one that "eats away the lining of the intestines". Can we see references for these studies please? Zidovudine is also apparently a "failed chemotherapy agent"(this is relevant how?) which was "approved on the basis of fraudulent human trials". Carl Williams is quick to cite a legal case brought by Anthony Brink against Glaxo-Smith-Kline; if HIV dissidents persist in claiming HIV trials were fraudulent they had better get hold of some good lawyers. (Oh, I believe Anthony Brink may be available since the collapse of his case against GSK).

Competing interests:   Attendance at drug company sponsored HIV conferences/meetings