Kazia Therapeutics’ (ASX: KZA) lead drug candidate paxalisib has been awarded rare paediatric disease designation (RPDD) for the treatment of a highly-aggressive childhood brain cancer known as atypical rhabdoid teratoid tumour (AT/RT).
The designation was handed down by the US Food and Drug Administration (FDA) and means Kazia may be entitled to receive a paediatric priority review voucher (pPRV) if paxalisib is initially approved for the cancer.
A pPRV grants the holder an expedited six-month review of a new drug application.
The vouchers are tradeable and have historically commanded prices in excess of $146 million.
Paxalisib was previously granted orphan drug designation (ODD) for AT/RT by the US FDA in June.
The FDA’s award of RPDD follows Kazia’s presentation of promising pre-clinical data for paxalisib in the treatment of AT/RT at an annual meeting held by the American Association of Cancer Research (AACR) in April.
Kazia chief executive officer Dr James Garner said it demonstrates the importance of childhood brain cancer in the overall paxalisib development program.
“Brain cancer is the most common cause of cancer death in children, but the outcomes in many forms of [this disease] have not improved in decades,” he said.
“We very much hope that paxalisib can make a difference to families affected by DIPG (diffuse intrinsic pontine glioma) and AT/RT, and we will be working closely with clinicians, researchers and the FDA to determine optimal ways to move the drug forward.”
Rare paediatric disease designation can be granted to drugs in development for diseases which: primarily affect children (under the age of 18 years); are serious or life-threatening; and report less than 200,000 new cases per year in the US.
A sponsor of a drug with RPDD may request a priority review voucher from the FDA at the time of a marketing application.
A voucher effectively shortens the FDA’s review period from 12 months to six months.
For a large company launching a billion-dollar drug, the six-month acceleration in regulatory reviews can be of substantial economic value.
In 2019, five paediatric PRVs were granted by the FDA.