The Committee for Proprietary Medicinal Products of the European Agency for the Evaluation of Medicinal Products has issued new guidelines on approval of anti-HIV drugs for use in patients who have developed resistance to many of the existing treatment options.
The guidelines will mean that anti-HIV drugs could be routinely approved in Europe before they go on the market in the United States, a major turnaround for the pharmaceutical industry. Bristol Myers Squibb has already obtained a European license for a new formulation of ddI, Videx-EC, but is still waiting for a US license.
A drug will be approved:
- If it demonstrates no cross-resistance in vitro against virus isolates which are resistant to one or more drugs of the same class
- If it is a drug of a new class with a unique resistance profile
- If it shows a superior pharmacokinetic profile to other drugs of the same class which might result in activity against strains with reduced susceptibility to other drugs of the same class
The report says that it will be preferable to license new compounds on the basis of studies in heavily pre-treated patients who still have some options left, rather than patients who have failed all available treatments.
A study in which the drug is added (or switched to) for 2-4 weeks will be sufficient to test whether the drug is active; a 16 week study in which the drug is added to existing therapy (or substituted for an existing component) will be sufficient to test efficacy.
After approval under exceptional circumstances, companies will have to provide agreed data each year to add to and extend the license. Drugs for use in untreated patients or less treated patients will continue to be subject to requirements for 24 week efficacy studies plus evidence of `added value', and will be compared with other drugs in terms of safety and efficacy.