AIDS TREATMENT UPDATE, Issue 38, February 1996
Keith Alcorn

In Europe however, new drugs to add to the existing trio of approved drugs (AZT, ddI and ddC) are still a long way away. Callers to AIDS Treatment Update have been asking how they can get 3TC and saquinavir, after reading promising trial results. The answer remains the same: although the drugs are now licensed for prescription in the USA, it may take six months to a year before the drugs are licensed in the UK. As one caller put it, "Why should I be denied something that's safe enough for Americans to take?".

There are three reasons for the USA's speed in getting new drugs to people with HIV. First, activists have put huge pressure on the Food and Drug Administration (FDA) to approve AIDS drugs quickly. Secondly, the Congress is now encouraging the FDA to get drugs for all diseases onto the market more quickly.

The third reason relates to the information that is required before a drug can be approved. Drug licences are only granted when a company can prove that a drug is safe and has some benefit in treating the condition it is prescribed for. Drug companies must provide a substantial amount of information about potential side-effects and their frequency. In the USA, the FDA and the drug companies begin to talk to each other early in the drug development process. By the time a company files a licence application they have generally anticipated the queries about safety and effectiveness that could arise, because they have been in dialogue for months or even years with the very people who will eventually process their application.

THE EUROPEAN SYSTEM

By contrast, drug companies have little guidance on what problems are likely to arise when they present all the information they have accumulated from clinical trials to the licensing authorities in Europe.

The European Union now has one central licensing authority, the European Medicines Evaluation Agency (EMEA), which approves new therapies, including anti-HIV drugs, for all fifteen member states. Until now countries such as the UK have lagged behind some other countries in approving anti-HIV drugs. For example, ddI and ddC approval took much longer in Britain than most other European countries due to the reluctance of the UK authorities to approve these drugs on the basis on changes in recipients' CD4 counts alone. Under the new system, once the EMEA approves a drug it can be marketed in every member state.

The EMEA is expected to approve stavudine, which is already licensed in the USA, sometime in the spring of 1996, with 3TC to follow sometime in the summer. Saquinavir and ritonavir are likely to be approved later in 1996, with indinavir likely to be the last of the current batch of protease inhibitors to reach the European market late in 1996.

There will probably be a delay of at least six months before a drug that is newly licensed in the USA is approved in Europe. There may also be differences in the indication. This is the term used to described the medical condition and the group of patients for which a drug is to be used.

RESISTANCE CONCERNS

It is possible that the EMEA will be more sceptical of the wisdom of making some of the new drugs available to large numbers of people immediately. For instance, some doctors think that new drugs may not be as safe as their rapid licensing in the US might suggest.

The concern is not necessarily over side-effects, but rather over a new drug's long-term effects in terms of closing off future treatment options. This has become a much starker issue since the results of the Delta trial. Delta showed that people who had taken AZT prior to beginning combination treatment with AZT plus ddI or ddC derived little or no benefit from the combination compared to those who had never taken AZT before - probably because they had developed AZT-resistant strains of HIV.

With new drugs which have been taken only by relatively small numbers of people for relatively short periods, there are more unknowns. For instance, there is the issue of whether taking one protease inhibitor may block your ability to benefit from other protease inhibitors in the future, due to the development of resistance. There is still fierce debate over what drugs to start treatment with and when to switch. It is quite possible that the European licensing authorities will take more time to consider these questions than the Americans did, and may restrict the use of the drugs accordingly.

THE COST OF THERAPY

While these factors do affect whether or not people can obtain new drugs, British doctors point out that the other major difficulty they face is paying for drugs after they have been approved.

Clinics are already debating ways that they can spend less on anti-HIV drugs, at a time when research increasingly suggests that the best therapy for HIV will require the use of more drugs earlier in the course of infection. No-one yet knows how these conflicting trends will be resolved.

9602
ATU3801

Copyright © 1996 - AIDS Treatment Update. Permission granted for noncommercial reproduction, provided that our address and phone number are included if more than short quotations are used. Subscription lists are kept confidential. NAM Publications 16a Clapham Common Southside, London, England SW4 7AB; TEL: 01-71-627-3200 (from outside the UK: +44-171-627-3200); FAX: 01-71-627-3101 (from outside the UK: +44=171-627-3101)  info@nam.org.uk  http://www.nam.org.uk