Rapros (Beraprost)
Rapros (beraprost sodium) is a drug in the prostacyclin (PGI2) family made by Toray Industries in Japan.
Beraprost belongs to the prostanoid family of drugs. These medications are vasodilators, i.e. they relax the blood vessels. Role of nitric oxide and prostacyclin as vasoactive hormones released by the endothelium (2007) Mitchell JA, Ali F, Bailey L, Moreno L & Harrington LS Experimental Physiology 93(1) pp141–147 says "Nitric oxide and prostacyclin are arguably the most important cardioprotective hormones yet described." This class of medication is commonly used in humans to treat pulmonary arterial hypertension, though beraprost is not the most effective drug for that purpose.
It is not uncommon to use heart medications for patients with CKD (see ACE inhibitors and ARBs above). Beraprost sodium improves survival rates in anti-glomerular basement mmbrane glomerulonephritis and 56 nephrectomized chronic kidney disease in rats (2013) Yamaguchi S, Inada C, Tamura M, Sato N, Yamada M, Itaba S, Okazaki S, Matsuura H, Fujii S, Matsuda F, Goto Y, Mochizuki H, Kurumatani H, Miyamoto M European Journal of Pharmacology 714 pp325-331 reports on trials of the medication in rats with kidney problems.
Toray Industries also produce a human medicine containing beraprost, which is licensed in Japan and other countries. Orally active prostacyclin analogue beraprost sodium in patients with chronic kidney disease: a randomized, double-blind, placebo-controlled, phase II dose finding trial(2015) Koyama A, Fujita T, Gejyo F, Origasa H, Isono M, Kurumatani H, Okada K, Kanoh H, Kiriyama T & Yamada S BMC Nephrology 16 pp165 reports on a short trial in humans which was trying to find the correct dose for kidney disease patients.
Nikkei Asian Review reports that beraprost was approved in Japan for the treatment of CKD in cats with effect from April 2017. A double-blind placebo-controlled multicenter prospective randomized study of beraprost sodium treatment for cats with chronic kidney disease (2018) Takenaka M, Iio A, Sato R, Sakamoto T & Kurumatani H Journal of Veterinary Internal Medicine 32(1) pp236-248 looked at the use of beraprost in CKD cats in 22 veterinary practices in Japan. The cats in the study had a USG below 1.035, creatinine over 1.6mg/dl (140 mmol/l) and a UPC ratio below 1.5. After six months creatinine and the phosphorus:calcium ratio increased in the placebo cats but not in the cats receiving beraprost. The study found that beraprost appears to be safe but "there was was no significant change in the USG in either group."
The manufacturer of Rapros claims it may slow the progression of CKD. At present the jury is out on whether ACE inhibitors and ARBs can do this and I think the same probably applies to Rapros.
I am not aware of any plans to launch Rapros outside the Japanese market.
https://www.felinecrf.org/proteinuria.htm#rapros
A Double-blind, Placebo-controlled, Multicenter, Prospective, Randomized Study of Beraprost Sodium Treatment for Cats with Chronic Kidney Disease.
https://www.ncbi.nlm.nih.gov/pubmed/29131397
There is much more to be found under the name Beraprost.
