Itraconazole for Eosinophilic Folliculitis: Interview with Marcus Conant, M. D.

A skin condition which can cause intense itching,
eosinophilic folliculitis, may respond to itraconazole, a new
antifungal. Marcus Conant, M. D., has seen good results in his
patients, and is about to start a study in San Francisco to
obtain authoritative information. The potential treatment was
first noticed by physicians in Europe. Itraconazole was only
recently approved in the U. S. ; before then, U. S. patients
obtained the drug abroad or from buyers' clubs.

We asked Dr. Conant to describe his use of the drug, and the
San Francisco trial he is planning with the developer, Janssen
Pharmaceutica.

MC: "Eosinophilic folliculitis is an unexplained
inflammatory infiltrate around the hair follicles in the skin,
which instead of just having nutrophils and lymphocytes at the
follicle, also has large numbers of eosinophils [a kind of
immune-system cell], suggesting that this condition may be an
allergic reaction to some organism in the skin. A number of
researchers have looked for an organism which causes the
condition, but nothing has been found consistently.

"In the past, what has been used to treat eosinophilic
folliculitis has been low doses of ultraviolet light, just enough
to cause a tan. Nobody knows why this works. High-dose
cortisone can also relieve the condition; but cortisone is
immunosuppressive, so it should be avoided if possible. Various
topical medicines have also been tried, none with much benefit.

"Last year physicians in Scotland reported that when
patients were treated with itraconazole [for other purposes],
they had seen the itching stop. I treated a few patients and
found that was true; I also tried fluconazole, a similar drug,
and ketoconazole for eosinophilic folliculitis, and they have not
been beneficial. We have now applied for investigational new
drug approval to test itraconazole in a series of patients, to
see if this observation can be confirmed scientifically.

"If this drug does in fact work, then either it is effective
against some organism which is not susceptible to the other
drugs, or it might be working through some other mechanism in the
hair follicle."

JJ: Itraconazole has been reported to concentrate in the
skin.

MC: "That's right. One way we expect that this drug might
be used, now that it is approved, is to treat someone with a
fungus in their nail for a month or so, then stop the drug since
it may stay there and continue to work. If this theory works,
you might only have to treat the patient for a month every three
or four months. The advantage is that you would not constantly
expose the liver to the drug.

"Itraconazole is also important because it has very good
activity against aspergillosis, a rare fungal infection.
Fluconazole and ketoconazole have some activity in this disease,
but less. Now that the drug is approved, physicians will learn
quickly what conditions it may be effective for where fluconazole
and ketoconazole have been less useful.

"Itraconazole, like ketoconazole, requires stomach acidity
to be absorbed; that is not true of fluconazole. And many
patients with less than 100 T-helper cells do not make enough
acid in the stomach. In our study, which will start next month,
we will measure itraconazole after oral administration with and
without a diet Coke given at the same time. Theoretically that
drink should put enough acid in the stomach so that the drug will
be absorbed. But we have to demonstrate that this really will
work.

"If people have eosinophilic folliculitis and would like to
work with us in the trial to show whether itraconazole is
effective, they should call Christopher King, 415/661-2614. He
will be administering this study."

JJ: For people who are not in the area or do not want to
join the trial, how have you been treating patients in the past?

MC: "The dose used in Europe was 300 mg per day of
itraconazole for about a month.

"Patients should have their liver functions followed. Liver
toxicity has been reported less with itraconazole than with
ketoconazole, but it can occur."