Some people claim it has benefits.
From my personal experience. In the early 2000's I ask my liver doctor about it. He said if you want to try it go ok but there is no conclusive evidence it will help those with HCV and to make sure to stop if any side effects. Took the higher cost supposedly best extract quality one for 6 months and noticed no difference for myself.
Today GT2 almost 3 weeks tx SoOV/RBV should have 2 week VL results in a day or two. Before starting treatment was told by treatment doctor not to take any herbs or supplements during treatment without checking first. He said not to take St Johns Wort specifically and even other liver "herbs" like milk thistle because not much information about interaction with Sovaldi is know. Why take any chances while on treatment that already has a high percentage SVR rate.
Some links about milk thistle
http://www.webmd.com/heart-disease/milk-thistle-benefits-and-side-effects
Is Milk Thistle Good for the Liver?
At this point, there is not enough scientific data to say whether or not milk thistle can help liver problems. Some early research suggests milk thistle may aid people with alcohol-related liver disease. Other studies show no improvement in liver function in this group of people.
http://www.mayoclinic.org/drugs-supplements/milk-thistle/background/hrb-20059806
Milk thistle (Silybum marianum)
Milk thistle products are popular in Europe and the United States for various types of liver disease. Although numerous human trials have been published, most studies have lacked a strong design and strong conclusive evidence.
http://www.rxlist.com/milk_thistle/supplements.htm
Milk Thistle
Are there safety concerns?
Milk thistle is safe for most adults. Milk thistle sometimes causes a laxative effect. Other less common side effects are nausea, diarrhea, indigestion, intestinal gas, bloating, fullness or pain, and loss of appetite. Milk thistle can cause an allergic reaction in people sensitive to plants in the Asteraceae/Compositae family including ragweed, marigolds, daisies, and other related plants.
I wish you the best..
Milk thistle can be beneficial also Foltix, maybe you can ask your doc to prescribe it. It's a prescription only mix of the vitamin B's. I know my Hep C friends who are on it are coming back with better lab results. Good luck and God bless.