Innovation Pharmaceuticals Inc (IPIX)

[KMBJN]

The black-box warning for Prurisol would be for hypersensitivity reactions to the drug, for people with HLA-B*57:01, as exists for abacavir.

Basically, everyone needs to be tested for HLA type before they receive Prurisol (abacavir acetate) or Ziagen (abacavir sulfate), since those with HLA-B*57:01 would be more likely to develop a potentially life threatening allergic reaction.

From Wikipedia:

"The mechanism underlying abacavir hypersensitivity syndrome is related to the change in the HLA-B*5701 protein product. Abacavir binds with high specificity to the HLA-B*5701 protein, changing the shape and chemistry of the antigen-binding cleft. This results in a change in immunological tolerance and the subsequent activation of abacavir-specific cytotoxic T cells, which produce a systemic reaction known as abacavir hypersensitivity syndrome.[18]"

Then again, as BK said, maybe the dose of abacavir in Prurisol would be low enough for it to be less of a problem.

I do recall exclusion of HLA-B*57:01 subjects in the Phase I Prurisol study:

"Positive test for HLA-B*5701 allele by certified laboratory"

http://clinicaltrials.gov/show/NCT02101216