Primary hyperoxaluria type 1 (PH1) is a rare disease affecting the kidneys caused due to accumulation of oxalate, which is generally filtered through the kidneys and excreted in the urine. Patients suffering from this disease are reported to have oxalate deposited in the kidneys and urinary tract. The oxalate combines with calcium to form calcium oxalate which results in formation of kidney and bladder stones.¹This may progressively cause damage to the kidneys leading to results in end-stage renal disease.²

Lumasiran has been approved as the first drug for treating patients suffering from primary hyperoxaluria type 1 (PH1) both in the US and Europe in both adult and pediatric patients. Lumasiran inhibits the production of oxalate. This was further evident from the phase 3 open-label trial studies. The study included 39 patients in the age group of more than 6 years. The patients received subcutaneous lumasiran monthly for 3 months followed by quarterly maintenance doses at 3 mg/kg. Results showed a 65% average reduction of oxalate in the urine among patients being administered lumasiran compared to an average reduction of 12% with placebo. Also, a normal 24-hour urinary oxalate level at 6 months was observed in 52% of patients receiving lumasiran, compared with no patients in the placebo group. The study also confirmed the safety and tolerability of the drug. No severe adverse effects were reported except mild injection-site reaction.^3,4

Lumasiran has been designated as Orphan Drug in both the United States and Europe. Is has also been regarded as Breakthrough Therapy and Rare Pediatric Disease Designations from the FDA.^3,4

Reference:

1. https://rarediseases.info.nih.gov/diseases/2835/primary-hyperoxaluria-type-1
2. https://www.alnylam.com/wp-content/uploads/pdfs/Lumasiran-Fact-Sheet.pdf
3. https://www.ajmc.com/view/market-of-sirnas-poised-to-expand-beyond-3-currently-approved-drugs
4. Zhang MM, Bahal R, Rasmussen TP, Manautou JE, Zhong X-B. The growth of siRNA-based therapeutics: Updated clinical studies. Biochem Pharmacol. Published online January 26, 2021. doi:10.1016/j.bcp.2021.114432