- Akebia Therapeutics has secured a tool that could help narrow the gap between its drug and a closer-to-market rival from AstraZeneca and Fibrogen.
- On Friday, Akebia effectively gained access to a regulatory fast pass just purchased by its partner, Vifor Pharma. In exchange for a $10 million payment, Vifor has agreed to hold onto the newly procured Priority Review Voucher, or PRV, until the companies decide what to do with it. Deal terms hold that the companies will either use the voucher on the approval application for Akebia's experimental anemia drug, or resell it and share the proceeds.
- Analysts at Piper Sandler predict that, with a voucher attached, the Food and Drug Administration could make an approval decision on Akebia's drug in the middle of 2021. That timeline would put Akebia and Vifor roughly six months behind AstraZeneca and Fibrogen, which have a similar anemia drug set to receive an approval decision by Dec. 20, 2020.
PRVs can be a handy tool for drug developers looking to beat a rival to market or to get a jump start on sales from an expected blockbuster. Yet they don't always work as intended.
One early example came from Novartis, which wanted its drug canakinumab, also known as Ilaris, approved for gouty arthritis and used a voucher to speed the review process. The FDA ended up rejecting the application, however, erasing any potential market advantage the voucher could have provided.
On the other hand, companies may miss out on millions of dollars if they don't have a voucher in their arsenal or don't use it on the right drug. One relatively recent analysis concluded that Merck & Co.'s Januvia, a type 2 diabetes medication, would have experienced a $793 million benefit had the company attached a PRV to its application.
The financial pressure surrounding PRVs is arguably even greater if a company spent money to acquire it. AbbVie, for instance, shelled out $350 million in 2015 to get its hands on a voucher held by United Therapeutics. AbbVie went on to successfully deploy the voucher on its rheumatoid arthritis drug Rinvoq, which the company expects to hit blockbuster status in the not-too-distant future.
Vifor, meanwhile, told Regulatory Focus before confirming to BioPharma Dive that it spent around $100 million to acquire its voucher from an unnamed seller.
According to Regulatory Focus, there are around 18 PRVs awarded by the FDA that have yet to be used. Some of the most recent awardees include Vertex, Merck, Sarepta Therapeutics and Bavarian Nordic, which sold its voucher in December to an undisclosed buyer for $95 million.
Akebia is now evaluating whether to use Vifor's voucher on vadadustat, a drug which inhibits an enzyme called hypoxia-inducible factor prolyl hydroxylase. The drug is under investigation as a treatment for anemia due to chronic kidney disease, for both dialysis-dependent and dialysis-independent adult patients.
That's the same mechanism of action and patient group that AstraZeneca and Fibrogen are targeting with roxadustat, an approval application for which was submitted in late December. Notably, the companies didn't use a PRV on the application, nor did the FDA grant their drug priority review.
"Now it's a horse race," wrote Christopher Raymond, an analyst at Piper Sandler, in a Tuesday investor note that explained the PRV could shorten vadadustat's review from 12 months to eight, and reduce roxadustat's potential time alone on market from a year to six months. Piper Sandler models global vadadustat revenue of $67 million in 2021 and $1.49 billion in 2025.
The Food and Drug Administration typically takes 10 months to review a drug approval application, though a priority review voucher or designation is supposed to push the agency to cut that time down to six months.