Dear Dr. Feinberg, I have written to you in the past about my brother that has PML. He was diagnosed in November, 1999. We were told by someone that has PML that we should go to the Mayo Clinic in MN because they did wonders for him. He had the Cidofovir and had great success with it. The problem is, my brother's doctor in PA feels that there has not been enough studies done on this drug and does not feel the side effects are worth taking a chance. I have placed a call to his previous doctor in NYC to see what his opinion is. Would you please give us your opinion on this? We feel there has got to be something out there that will help him improve more than he has. He has come along way since his lowest point in February, 2000 but he still has a long way to go. I will not give up until I have exhausted every possibility!! Thanks for taking the time to answer my question. You have been a great help since my brother became ill.

There has been limited formal study of cidofovir for PML, but so far the results aren't very encouraging. The drug is active in the lab against the JC virus that causes PML, but often activity in the lab doesn't translate into clinical benefit. There are also toxicities associated with its use, especially abnormalities of kidney function.

That said, if your brother hasn't responded adequately to HIV meds alone, it may be worth considering a course of cidofovir, just in case it may help if you're willing to accept the possibility of some toxicity (which can be minimized by careful monitoring before subsequent doses and adequate hydration). Good luck!