Oral Amphotericin Receives Orphan Drug Status

Submitted by Aspergillus Administrator on 19 October 2010

Amphotericin has long been a highly effective antifungal drug and is still widely used to treat aspergillosis. One of its strengths is that it attacks the cell wall of the fungus in a way that is highly specific to fungi (& insects) so the drug itself is potentially low in toxicity to humans. Most other available antifungal drugs (azoles)  attack the cell membrane but as human cells also have cell membranes there is potential for toxicity to human cells as well as fungal cells. This requires clinicians to carry out careful dose management.

Unfortunately amphotericin has poor solubility in water so cannot be given to patients without dissolving in substances that are fairly toxic to some patients, particularly affecting kidney and liver. This makes this drug tricky to give, requires accurate dose management and cannot be given as a pill or capsule as it will not dissolve in the stomach.

Fortunately there has now been a breakthrough in reformulation of amphotericin which we reported last year. The new drug is referred to as iCo-009. iCo-009 has already been shown to be able to achieve similar drug levels in the blood compared with giving its predecessor by intravenous injection, and there have been only low levels kidney toxicity, albeit in animal tests so far.

We can now report that the development of that drug has received another boost. iCo-009 (iCo Therapeutics) has been awarded orphan drug status by the American drug regulatory body the US Food and Drug Administration (FDA). This status is awarded to drugs that are intended to treat rare diseases and entitles them to extra funding to aid development, so it is great news for this next generation of amphotericin drugs and great news for everyone looking for antifungal drugs with fewer side effects.