FDA Tysabri/pml info
 

My daughter in-law found some info that I wanted to pass along. Not much different except when you click on "Info For Health Care Professionals" it states minimal chance for pml after 35 infusions.

http://www.fda.gov/Safety/MedWatch/S...afetyAlertsfor HumanMedicalProducts/ucm182667.htm

Hi Linda,

Your link didn't work so I tried to link to it here, maybe this one will work?

http://www.fda.gov/Drugs/DrugSafety/.../ucm107198.htm

[QUOTE=Grammie 2 3;570658]My daughter in-law found some info that I wanted to pass along. Not much different except when you click on "Info For Health Care Professionals" it states minimal chance for pml after 35 infusions.

http://www.fda.gov/Safety/MedWatch/S...afetyAlertsfor HumanMedicalProducts/ucm182667.htm[/QUOTE

The FDA stated that there is limited experience past 35 infusions. No way to tell what the risk is past 35 infusions until more patients have taken the drug for that long.

I'm not sure where you are reading that, but what I see is:

"The risk for developing PML appears to increase with the number of Tysabri infusions received. The number of monthly infusions of Tysabri in the 13 patients who developed PML ranged from 12 to 35 infusions. The average number of infusions received before the diagnosis of PML was 25. There is minimal experience in patients who have received more than 35 infusions of Tysabri."

So, while they seem to be recognizing that the more infusions a person gets, the more the risk there is for them to develop PML ... they don't have enough patient experience to determine how high the risk might go beyond 35 infusions.

Cherie

Cherie,

Without enough usage experience there is no way to tell what the risk is (whether it might be higher or lower or the same). Certainly depends upon what the risk factors for developing PML are. Time certainly seems to be somewhat of a factor (No PML before 12 months) but what are the others?

I would hope they are following those that were in the trials that are still taking Ty post marketing. Of those we haven't heard of any pml cases.

Grammie,

They're following thousands of patients in STRATA and Tygris trials, through the TOUCh program, and in investigation of the PML cases. I've heard rumblings that they may be rolling out a leukocyte assay with data on how it may indicate risk of PML in the near future. Unfortunately, proof that it works will require the passage of time with no or much fewer PML cases.

Chris

According to the FDA, "time" is relative to the number of infusions:

So, if they are correct, the more infusions you have, they are predicting the bigger your risk of contracting PML ...

Cherie

That would be people who are currently at 35+ infusions, and they are saying there aren't enough people yet to assess this.

Cherie

I would like to read up on this. Where do you find this info ? Since they came up with 1/1000 after the trials I figured there were 3,000 in the trials. If only half stayed on Tysabri and you add those post marketing I would think they could make an assessment:confused:
Thanks,
Linda