So now that we know that ZS-9 lower potassium, how much do you think it will cost?

One of the only positive trials at Kidney Week’s Late Breaking Trials Session was ZS-9, a novel potassium binding crystal that hopes to take the place of Kayexalate (Sodium Polysterene) in the hyperkalemic cocktail.

I wrote about the trial for eAJKD and was quoted in an article for MedPage Today.

Here is the skinny:

  • ZS-9 uses potassium specific pores to bind potassium rather than a cation exchange resin. It is highly specific for potassium, especially when compared to SPS.
  • In the phase 2 trial 10 grams lowered the potassium by 0.04 mEq/L per hour
  • In the phase 3 (753 patients!) trial the 10 gram dose lowered the potassium 0.78 mEq/L in 14 hours
  • No diarrhea
  • GI side effects were equal in the placebo and drug arms
I suspect this drug is on a smooth glide path for approval. My question is how expensive will it be? My guess is $200 per 10 grams. Please add your guess or over-under bet to the comments or @kidney_boy on Twitter.