TOPIC:

I have been looking at the prescribing information here:
fixhepc.com/forum/forum-gp-cheat-sheet.html

"Medications (Daclatasvir and Ledipasvir in particular have many interactions) you can check with this tool www.hep-druginteractions.org/checker

I checked with the tool and it is not showing any interactions for dac and led. It's giving a green light.

So which is correct?
Thanks,
dt

Oh duh! I see that the prescribing info meant that both dac and led have many interactions with OTHER drugs.
I was thinking it meant they have many interactions with EACH OTHER.

Anyway, I am still unclear on the subject of whether dac and led have interactions with each other. I cannot find any information which suggests that they do. I also cannot find any evidence which proves that they don't. I want to know if the concentration of either drug will be lowered by the presence of the other during a switchover from led to dac, while keeping sof the same?

Possibly this is still one of the many as yet unanswered questions about using the DAAs.

dt

PS
I meant to say "efficacy', not "concentration" which may not be the same thing.

I suspect there is little research on what you are asking as:

- It would require crosslabel trials which tend to be expensive.
- the standard treatment approach seems to be to use one NS5A inhibitor thoughout treatment and if that treatment fails to retreat preferably using another NS5A inhibitor that expresses itself via a different path if such an drug exists. This would apparently reduce any risk of resistance effecting the retreatment. I don't know whether Dac and Led differ sufficiently to do that or whether they are entirely analogous.

I'm not a scientist just an interested reader so the above is just my take on it.