Biotech Values

[DewDiligence]

Re: Tyzeka resistance

Viral resistance to a drug like Tyzeka only matters when the drug works at suppressing the HBV virus in the first place. When the drug does not work, who cares if the patient develops a resistant strain?

Thus, the most relevant resistance rates for Tyzeka that have been disclosed are not the aggregate numbers cited by Werber but rather these (from NVS’ PR yesterday, #msg-14377860):

“For telbivudine-treated patients who achieved PCR negativity at week 24, the per-protocol rates of resistance at two years were 4 percent in HBeAg-positive patients and 2 percent in HBeAg-negative patients. Per GLOBE study protocol, resistance was defined as HBV DNA return to >5 log, or to within 1 log of baseline.”

It would be nice to know the resistance rates for patients who were PCR-negative at later time points and I’m hoping NVS and IDIX will disclose those numbers. But the main point is that the numbers cited by Werber are essentially anti-IDIX propaganda in the same vein as his preposterously low sales projections.