Macrocyclic peptides are designed to engage complex targets like biologics but pass through cell membranes like small molecule drugs.
Argenx has entered a multi-target research pact that could be worth up to $1.5 billion with Unnatural Products, Inc.—also known as UNP—to advance oral macrocyclic peptides for several “traditionally ‘undruggable’” disease targets.
Tuesday’s agreement involves a “double-digit million-dollar upfront payment” to UNP, though the companies did not provide an exact amount. UNP will also be eligible for up to $1.5 billion in future research, development, regulatory and commercial milestones and option commitments. California-based UNP is also eligible to receive tiered royalties on net sales of products arising from the collaboration.
In an email to BioSpace, a spokesperson for UNP noted that Tuesday’s announcement is the largest licensing deal to date in the macrocyclic peptide space. Argenx has also pledged to participate in UNP’s upcoming series B fundraising round, the spokesperson added.
At the center of this partnership is UNP’s proprietary drug discovery platform, an AI-driven engine that can generate synthetic peptides that mimic macrocycles. These naturally occurring molecules can bind to complex targets like biologics do, but can easily move through the cell membrane similar to small-molecule drugs.
Under the terms of Tuesday’s agreement, UNP will use its macrocyclic peptide technology to discover orally available drug candidates for multiple targets as determined by argenx. UNP will usher these molecules through early assessments until investigational new drug-enabling studies, after which argenx will have the option to take them into the clinic.
Argenx’s business is currently highly dependent on one asset: the FcRn blocker efgartigimod, which is approved as Vyvgart for generalized myasthenia gravis (gMG). A reformulated version of the drug called Vyvgart Hytrulo—which contains other components that allow it to be delivered subcutaneously—is also approved for gMG as well as chronic inflammatory demyelinating polyneuropathy (CIDP), according to the biotech’s website.
In April, the FDA approved a prefilled syringe version of Vyvgart Hytrulo for gMG and CIDP.
The Vyvgart franchise brought in $2.2 billion in 2024—earnings that could be put at risk in coming years once patent protections for the drug expire. Vyvgart is protected through at least 2033, but with Tuesday’s deal, argenx appears to be in the process of expanding and diversifying its pipeline. The biotech is also working on the complement blocker empasiprubart for CIDP, multifocal motor neuropathy and other indications, as well as ARGX-119, a MuSK-targeting candidate for amyotrophic lateral sclerosis and congenital myasthenic syndrome.
