Dr Belostotsky is Associate Professor in the Division of Pediatric Nephrology. He completed his training in this subspecialty at Great Ormond Street Hospital and Royal Manchester Children Hospital in the UK and joined McMaster in 2011. His clinical interest is pediatric nephrolithiasis, and he runs McMaster kidney stones clinic since 2012. Primary hyperoxaluria is a rare cause of nephrolithiasis but caries a significant risk of kidney failure and mortality. Until recently combined liver kidney transplant was the only cure, but new RNA therapies are promising to change this. In this session of Grand Rounds, Dr. Belostotsky reviews pathophysiology of oxalate production and excretion, and challenges of previous available therapies. He also introduces two RNA medications: Lumasiran (approved by Health Canada in March 2022) and Nedosiran (currently going through phase 2-3 trials).