Allena claims orphan status for 'devastating' rare disease therapy

X-ray of kidney stones. (Wikipedia)

Allena Pharma has been granted orphan status by the FDA for a drug to treat primary hyperoxaluria, a rare disease that causes kidney and bladder stones and can lead to kidney failure and death.

The drug—called ALLN-177—is a non-absorbed formulation of an enzyme designed to break down a substance called oxalate in the gastrointestinal tract. Normally high levels of oxalate in the body are passed in the urine but in hyperoxaluria the system breaks down, leading to the formation of calcium oxalate crystals in the urinary tract.

Primary hyperoxaluria is caused by an inherited defect that leads to an overproduction of oxalate in the liver, and according to Allena affects around 1 in 58,000 people—which would be equivalent to around 5,000 people in the US as a whole. People with the disease usually develop end-stage kidney disease in their twenties or thirties and right now the only therapy is dialysis and a transplant. ALLN-177—an oral formulation of oxalate decarboxylase—is in early-stage clinical testing for primary hyperoxaluria, according to Allena's pipeline.

"Primary hyperoxaluria is a devastating disease for patients and their families," said Craig Langman, M.D., a specialist in kidney diseases at Northwestern University and Lurie Children’s Hospital in Chicago." We desperately need better therapeutic options to treat this disease."

News of the orphan status for ALLN-177 comes as the privately-held company's backers are waiting news from a pair of phase 2b trials of in patients with kidney stones caused by secondary hyperoxaluria, where the disease is caused by a high intake of oxalate-rich foods like spinach, nuts and French fries, or other factors such as changes to the bacteria residing in a person's gut.

Around 2.6 million Americans suffer from kidney stones, and assuming ALLN-177 hits the mark in trials and reaches the market it will be interesting to see how Allena handles commercializing the drug both for a common condition and a very rare disease. A spokesperson for the company told FierceBiotech that "the phase 2 program for secondary hyperoxaluria has been completed and the results will be presented at the scientific meetings in the fall."

Allena licensed rights to ALLN-177 from Althea Technologies in 2012 for an undisclosed sum, and raised $53 million in a financing round in 2015 to help fund its two secondary hyperoxaluria trials.  At the time is said it was hoping to start a phase 3 program by the end of 2016.

The company isn't entirely alone in developing therapies for hyperoxaluria, although the pipeline is pretty thin. Dicerna and Alnylam both have gene-silencing therapies targeting another enzyme called glycated oxidase—respectively called DCR-PHXC and ALN-GO1—in early-stage development. Meanwhile, new start-up Captozyme is following Allena's lead with an oxalate-degrading enzyme (CZ2294) given orally that is also at the gestation stage.