Moxidectin hasnt been approved for human use (yet) however it has passed phase 3 trials (ie safe for larger scale efficacy testing) for onchocerciasis, aka river blindness, a worm infection.
In this trial the dosages tested were 2mg, 4 mg or 8 mg and there were no serious side effects. It was also effective:
Moxidectin is being looked at for scabies, and it is intersting because it has a long half life, so continues to act for some weeks.
This recent review covers it: http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0004389
Dosing trials have been tried out on pigs to test efficacy for scabies, at 0.3 ug/kg (that is 0.3 micrograms per kilogram)see study:
It was also more effective than ivermectin here.
The dose used in horse wormer is 0.4 ug/kg for a variety of nematode. It is also of interest because of its long half life - from the above reading, this is around 20 days in humans I think. In the SPC for the horse paste it states a persistent efficacy of 2 weeks, with egg suppression for longer.
I would guess a dose of 0.3 ug/kg would cure scabies based on the study in pigs. The human trial however went to a dose of 8 mg which is actually probably half that, and was effective.
Because the horse paste (sold as Equest) in the UK is at 0.4ug/kg, the paste syringe allows you measure out a dose per kg. So if you wanted to take 0.3 ug/kg you would extract to 3/4 of your weight on the syringe for that. As mentioned the first trial I posted used lower amounts, so you could half that if being cautious, and I suggest you. For if it has a long half life you could space it out.
Personally, I would start on the lower side and check for any reactions first and be cautious. I am not a doctor and cant recommend this, because you could have a reaction to it (though the same is true for ANY medication). (That said it seems quite likely this drug will be a possible break through for various parasitical conditions in the nearish future).
I realise this is 7 mo late, but hey, maybe it will help someone else.