Hello Honker,
1b is the genotype of choice (if choice was an option).
Here are the overall stats for Sof/Led
Sofosbuvir Ledipasvir
NAIVE
default: svr: 97%, trials: ION-1 98% (142/145) ION-3 96% 96% (165/172) Aggregate 96.8% (307/317)
gt1a: default: svr: 97%, trials: ION-1 98% (142/145) ION-3 96% 96% (165/172) Aggregate 96.8% (307/317)
gt1b: default: svr: 99%, trials: ION-1 100% (67/67) ION-3 98% (43/44) Aggregate 99.1% (110/111)
F4
default: svr: 97%, trials: ION-1 97% (32/33)
w12: svr: 97%, trials: ION-1 97% (32/33)
w12riba: svr: 100%, trials: ION-1 100% (33/33)
w24: svr: 97%, trials: ION-1 97% (31/32)
w24riba: svr: 100%, trials: ION-1 100% (36/36)
FAIL
default: svr: 94%, trials: ION-3 94% (102/109)
w12: svr: 94%, trials: ION-3 94% (102/109)
w12riba: svr: 96%, trials: ION-3 96% (107/111)
w24: svr: 99%, trials: ION-3 99% (108/109)
w24riba: svr: 99%, trials: ION-3 99% (110/111)
These don't show GT1 8 week results, but ION-3 does:
www.hepatitisc.uw.edu/page/treatment/clinical-trials/61
Now if you look at slide 5 you see 94% and probably go - ick!
But if you look at slide 6 you will see that of the 215 people in the 8 week arm only 2% (2/123) with viral load < 6 million failed versus 10% (9/92) who had higher viral loads.
On slide 9 you will see that 18% had NS5A RAVs at baseline (of who the vast majority still got to SVR)
Not shown in the slides are the SVR rates comparing 1a and 1b in ION-1 and ION-3 but the upshot of that was that 1b is a little more responsive than 1a
With 1b, treatment naive, non cirrhotic, Viral load < 6 million 8 weeks Harvoni offers 98-99% cure rate. Treating past that point is probably a waste of time and money because by 8 weeks the chances are a patient is cured. The last 4 weeks might help somebody in that remaining 2%, but for most patients they don't need it.
That said for ~ $500 USD I would take the full 12 weeks myself for peace of mind, but if finances are an issue and you're treatment naive, not cirrhotic and have a VL < 6 million 8 weeks is not a bad option for both GT1a and GT1b.