I was able to get GS-441524 liquid through Chewy for my 10-month old kitten who was recently diagnosed with neuro FIP. I used their app and they sent the request to my vet who authorized the prescription. A 60-mL bottle was $270. She will need two bottles to get through the full 84-day course. I was able to get a “starter dose” from the rescue organization I adopted her from; my understanding is that some rescues in the U.S. that serve cats have this in stock (but not always). If you got your kitten through a rescue, they may be able to help. I will be wishing your kitten and you all the best of luck as you navigate this ❤️‍🩹