Eyeing the next regulatory frontier in autoimmune disease, argenx is spending $102M on a speedy future review for its "pipeline-in-a-product" efgartigimod.
Bluebird bio has sold argenx a rare pediatric disease priority review voucher (PRV) for $102 million, the companies said Wednesday. Bluebird got its hands on a pair of PRVs following the U.S. approval of its beta thalassemia gene therapy Zynteglo in August, plus its green light for Skysona in the rare neurological disorder cerebral adrenoleukodystrophy (CALD) in September.
For its part, argenx specified that the FDA voucher will go toward a future marketing application for its first-in-class Fc receptor blocker efgartigimod. The drug snagged its initial U.S. green light as Vyvgart in generalized myasthenia gravis (gMG) in December 2021.
Regarding the company’s efgartigimod pipeline, Argenx recently filed for FDA review of a subcutaneous version of Vyvgart, which is currently administered intravenously. The company is using a separate PRV it bought from Bayer in 2020 for that below-the-skin formulation, an argenx spokesperson said via email.
The drug is also in phase 3 studies in both IV and subQ formats for primary immune thrombocytopenia. Plus, intravenous efgartigimod is being studied in kids and teens with gMG from ages 2 to less than 18 years old. Vyvgart’s gMG approval last winter was in adults.
Argenx says it’s already validated the drug’s potential in four autoimmune diseases, with plans to be active in 15 disease targets by 2025, according to CEO Tim Van Hauwermeiren.
“With a priority review voucher available, we hope to expedite the approval process for one of our current or future indications to more quickly reach the patients who are in serious need of a new treatment option,” the chief executive said in a company statement.
As for bluebird, the sale has helped “significantly” boost the company’s financial outlook as it launches its pair of gene therapies in the U.S. and prepares for the submission of a third to the FDA, CEO Andrew Obenshain said in a statement. The company says it’s continuing to look into other financing opportunities, too, which could include the sale of its second voucher.
Bluebird was navigating dark skies earlier this year, but it’s hit a light patch thanks to twin gene therapy approvals in the U.S. this past summer. Bluebird also set records with the prices of its new meds: Zynteglo in beta thalassemia rolled out at a cost of $2.8 million, while Skysona costs $3 million per treatment. Both drugs are intended to be single-dose therapies.
Since then, however, a hemophilia gene therapy from CSL Behring and uniQure has taken the pharma pricing record, boasting a price tag of $3.5 million before discounts.
Pricing previously proved a point of contention for Zynteglo in Europe, where bluebird ultimately pulled its gene therapy from the market in 2021.
To help blunt the cost of Zynteglo stateside, bluebird's access strategy revolves around a one-time upfront payment with the option of a rebate for beta-thalassemia patients who don't achieve transfusion independence. That could in turn help patients recoup up to 80% of the one-time treatment cost, bluebird Chief Commercial Officer Tom Klima explained in an interview earlier this year.
Meanwhile, bluebird won’t offer an outcomes-based payment for Skysona because the rarity and complexity of CALD makes such an arrangement “extremely challenging to implement for both bluebird and payers,” Obenshain told investors during a conference call in September.
Editor's note: This story has been updated with a comment from argenx.