As with HIV-positive adults, the goals of treatment in children are to improve quality of life, prolong survival and prevent complicating infections. In addition, and specific to children, is the potential to restore and sustain normal growth and development.

Over the past ten years, treatment options for children with HIV have changed dramatically. In resource-rich nations, access to and availability of medications is similar to those used with adults. In the UK all classes of medications are currently available for use in children. However, not all are in formulations which are “child-friendly”; by this, we mean formulations that are easy for children to take.

Clinical trials designed to evaluate the safety and effectiveness of anti-HIV drugs are predominantly carried out in adults, though there have been numerous trials with children in recent years.

In Europe, the Paediatric European Network for the Treatment of AIDS (PENTA) carry out such trials.

Additional specific research into treatments for children is urgently needed, as the results of studies in adults cannot always be applied directly to children. The main reasons for this are:

• Some drugs are handled differently in children’s bodies, which may affect the dose that is required. Pharmacokinetic (PK) tests, also known as therapeutic drug monitoring, are a vital tool in treating children with HIV.
• Young children have immature immune systems, which may be less effective at fighting HIV infection.
• CD4 counts have to be interpreted differently from adults, as they can be much higher in infants than in adults – see “CD4 percentage” above.
• The natural history of HIV differs between children and adults.

Research studies looking at HIV treatment use in children have been relatively short-term. However, children will potentially be exposed to antiretrovirals for very long periods of time, and this exposure occurs at a time when their bodies are growing. No-one knows the long-term effects of this.

Treatment regimens

In the UK, children starting on treatments will generally start on a triple combination. However, for those with high viral loads and very symptomatic disease, quadruple (four drug) therapies have been used. This should ideally spare at least one class of drug.

Deciding when to start treatment in children and what to start with remains controversial. There are no data available to suggest that PI-containing or sparing regimens have greater clinical efficacy.

Side-effects

Toxicities associated with antiretrovirals are broadly similar in children and adults. The most common side-effects in children are gastrointestinal symptoms and rashes. However, lipid abnormalities and lipodystrophy have been increasingly reported.

As with adults, the long-term effects of antiretroviral therapy are as yet unknown.

In the UK, for babies born to HIV-positive mothers and who have been exposed to antiretroviral therapy in utero, reporting to the British Paediatric Surveillance Unit (BPSU) is required to monitor any long-terms effects of antiretrovirals.

Dosing

Dosing of antiretroviral therapy for children differs from adults. Doses are generally calculated on weight or surface area. In some instances, paediatric doses of antiretrovirals may exceed adult doses, with children requiring larger doses. This applies particularly to protease inhibitors. Children’s livers are more efficient and process drugs faster. However this varies widely from child to child.