Summary
The principle behind Adamas’s triple combination development for influenza is a good one. There is clearly a need for improved treatments, as the latest wave of swine flu is now showing. Oseltamivir (Tamiflu) and ribavirin are reasonable drugs to select but the third component, amantadine, may prove the weak link.
Analysis
The once-shunned concept of using combinations – fixed or otherwise – for infective diseases, has become well accepted since the early 1990s in areas of infection as diverse as HIV, hepatitis B and C, tuberculosis and malaria. It is a useful initiative to try combinations in other badly served areas, including flu.
But the candidate drugs for fixed combinations have to be strong ones if such a concept is to work out in clinical practice. Of the three drugs selected for combination by Adamas Pharmaceuticals, Inc., amantadine appears to be the potential weak link. It is a traditional, rather ineffective drug for influenza of limited value in treatment whose main use is in prophylaxis. Adamas will need to show that each component in the triple combination provides a significant clinical benefit. This could prove difficult in the case of amantadine.
Perhaps as a less ambitious first step, a simpler, two-component combination might prove easier to develop and obtain approval for. But possibly the scope for intellectual property coverage which Adamas has on the triple combination does not exist with a simpler combination.
John Ansell consults with leading institutions through GLG
Analyses are solely the work of the authors and have not been edited or endorsed by GLG.
