Johnson & Johnson, Pfizer, Argenx and more are unlocking new immunology targets and looking to improve on existing ones in an attempt to catch some of the magic brought about by AbbVie’s Humira and Sanofi and Regeneron’s Dupixent.
Aside from cancer—and in recent years, obesity—immunology is one of biopharma’s hottest therapeutic areas, producing some of the biggest franchises in the industry’s history.
AbbVie’s Humira, approved for a wide range of immune-mediated conditions, was the world’s top-selling drug for nearly a decade, from 2012 to 2020. The anti-TNF antibody was only dethroned in 2021 by Pfizer and BioNTech’s COVID-19 vaccine Comirnaty, but Humira remained a commercial juggernaut that year, slipping only to second with $20.7 billion in sales.
“AbbVie remains the commercial benchmark,” Stuti Mahajan, consulting manager at DelveInsight told BioSpace in an email interview. Even as Humira drops off after losing key patent protections, Mahajan noted, the pharma has built a robust immunology portfolio with the IL-23 blocker Skyrizi and the JAK inhibitor Rinvoq, both of which were among the industry’s best-selling drugs last year.
Then there’s Sanofi and Regeneron’s IL-4Rα blocker Dupixent, another immunology powerhouse approved for a wide array of indications—including asthma, urticaria and atopic dermatitis—that brought in $17.8 billion revenue in 2025. But Dupixent, too, is nearing the end of its primary revenue years, with key U.S. exclusivity lasting into 2031.
To take advantage of these openings in the massive immunology and inflammation (I&I) market, many other drugmakers—big and small—are advancing novel and innovative mechanisms for immune-driven diseases.
There are the usual Big Pharma suspects, such as Johnson & Johnson, which Mahajan contended has “the most strategically complete portfolio” with IL-23 blockers Tremfya and Icotyde plus the FcRn inhibitor Imaavy and additional programs.
Bristol Myers Squibb and Merck are also challengers in the I&I space, Mahajan said. BMS is combining the TYK2-targeting Sotyktu with next-generation cell therapies, while Merck is proposing the TL1A inhibitor tulisokibart for ulcerative colitis and Crohn’s disease. Meanwhile, smaller specialists like Protagonist Therapeutics, argenx and Oruka Therapeutics are also advancing novel assets to address emerging pathologic pathways or improve upon current approaches to well-established disease drivers.
Here, BioSpace looks at six of the biggest immunology targets and the companies tackling them.
J&J, Argenx, more home in on FcRn
Because of how central it is to autoimmune diseases, FcRn has become one of the bigger immunology targets, according to Matt Phipps, group head of biotechnology equity research at William Blair. The protein, a receptor expressed by tissues throughout the body, recycles IgG antibodies and prolongs their lifespan—in turn sustaining the activity of autoreactive antibodies.
Several biopharma players have focused their drug development efforts on FcRn, Phipps told BioSpace via email. Not least of these is Johnson & Johnson, which owns Imaavy, a monoclonal antibody approved for generalized myasthenia gravis (gMG) and warm autoimmune hemolytic anemia. J&J is also testing Imaavy for systemic lupus erythematosus. Data from a Phase 2 trial demonstrated significant reduction in disease activity, according to a June readout. A late-stage study in this indication is ongoing.
Imaavy is also currently in development for Sjogren’s disease, fetal and neonatal alloimmune thrombocytopenia and idiopathic inflammatory myopathy.
Also in the FcRn arena is argenx. The biotech’s only commercial franchise is the FcRn inhibitor Vyvgart, approved for gMG. A subcutaneous formulation of the drug, called Vyvgart Hytrulo, is approved for gMG and chronic inflammatory demyelinating polyneuropathy. The biotech continues to study the asset in other immunology indications, such as immune thrombocytopenia and Graves’ disease.
Other companies targeting FcRn include Immunovant with imeroprubart, also known as IMVT-1402, which is in Phase 3 studies for a range of autoimmune conditions—though the company recently stopped pursuing lupus after a mid-stage failure—and UCB Pharma with the FDA-approved Rystiggo.
Mahajan agrees that FcRn is currently one of the most valuable immunology targets, offering “the broadest theoretical pipeline-in-a-product potential.”
STAT6 could pave path to ‘oral Dupixent’
Another immunology target attracting significant attention is STAT6, a signaling pathway that plays a central role in the activity of B cells—the immune players that produce antibodies. Faulty regulation of this pathway is known to result in a host of disorders, such as atopic dermatitis, asthma and food allergies.
STAT6 “is clearly of interest to people,” William Blair’s Phipps told BioSpace, referring to the target’s potential to produce an “oral Dupixent.” That blockbuster antibody targets IL-4 and IL-13, both of which lie upstream of STAT6 in the immune cascade.
One leader in this space is Kymera Therapeutics, which is working on the orally available degrader KT-621, being tested for atopic dermatitis and asthma. Phase 1b data presented in March demonstrated “deep STAT6 degradation” at both 100-mg and 200-mg dose levels in patients with moderate-to-severe atopic dermatitis, with median reductions of 94% in the skin and 98% in the blood, Kymera said at the time. The candidate also elicited “robust reductions” in several disease-relevant type 2 inflammatory blood biomarkers.
The early-stage study’s primary endpoint is safety, which the March readout found to be “favorable,” according to a company presentation. There were no serious or severe adverse events, nor did any of the patients drop out due to treatment-emergent adverse events (TEAE). Data from the Phase 2b BROADEN2 study are expected by the end of this year.
Also in the STAT6 race are Nurix Therapeutics and powerhouse partner Sanofi. Together, the companies are advancing the oral STAT6 degrader SAR448272/NX-3911, which last month advanced into Phase 1 development for type 2 inflammatory diseases.
Sanofi in April 2025 licensed an undisclosed Nurix program targeting a previously undruggable transcription factor for autoimmune diseases for $15 million upfront and the possibility of up to $465 million in milestones. The companies first came together in December 2019 in a multi-year collaboration to advance targeted degraders in which Sanofi paid Nurix $55 million upfront.
Next-gen IL-13/IL-4 blockers seek to improve on Dupixent
While the STAT6 developers seek to package the Dupixent magic in a pill, another group of drugmakers is developing next-gen molecules that could improve upon the blockbuster drug’s already-impressive efficacy profile, H.C. Wainwright Senior Analyst Mitchell Kapoor told BioSpace in an email.
Among the companies leading this charge are Eli Lilly and LEO Pharma, he said, which own Ebglyss and Adbry, respectively. Like Dupixent, both of these medicines are antibodies that disrupt the IL-13/IL-4 pathway and are approved to treat moderate-to-severe atopic dermatitis.
Many others still in the clinic could not only improve upon Dupixent’s efficacy but also allow for less frequent dosing, Kapoor said. These include Aclaris Therapeutics’ bispecific therapy ATI-052, which blocks IL-4 and TSLP, another crucial immune signaling molecule. Phase 1a data in January showed favorable safety outcomes for the asset, as well as a potential “best-in-class” pharmacokinetic profile, according to the biotech. Aclaris expects topline data from Phase 1b proof-of-concept trials in atopic dermatitis and asthma in the second half of this year.
Kapoor also pointed to Sanofi, which is taking a similar approach with the bispecific therapy lunsekimig, which works by targeting TSLP and IL-13. In April, the company announced mid-stage data showing that lunsekimig improved symptom burden in patients with asthma and rhinosunisitis, but failed to ease severity in a Phase 2b trial of atopic dermatitis. Sanofi is also testing the asset for chronic obstructive pulmonary disease (COPD).
Pfizer, meanwhile, is developing the trispecific molecule tilrekimig, which targets IL-13, IL-4 and TSLP. A Phase 2 readout in March demonstrated statistically significant improvements in eczema severity at 16 weeks, encouraging the pharma to advance the asset into late-stage studies for atopic dermatitis in 2026. Tilrekimig is also being studied for asthma and COPD.
IL-17/IL-23 still fertile for innovation after several approvals
Arguably among the most-addressed disease drivers in the immunology space are IL-17 and IL-23, cytokines that lie close to each other on the inflammation signaling cascade. Secreted by immune cells in response to certain stimuli, IL-23 is more upstream and works to activate helper T cells, which in turn produce IL-17.
Both cytokines help kick off the inflammatory response—and therefore offer attractive opportunities for drugmakers to intervene.
Indeed, some of the industry’s biggest immunology players and franchises target IL-23 or IL-17, including Novartis’ Cosentyx, Johnson & Johnson’s Tremfya and AbbVie’s Skyrizi.
But while there are already several drugs on the market addressing these targets, Phipps argued that there is still a lot of room for development in the space as companies make headway with oral options.
H.C. Wainwright’s Kapoor agreed, pointing in particular to IL-23, which he said “remains attractive” as the lead target in psoriasis as novel products emerge with more convenient dosing schedules.
In March, for instance, J&J won the FDA’s approval for Icotyde, an oral IL-23 receptor blocker indicated for severe plaque psoriasis. There’s also Takeda, which is developing zasocitinib, an oral drug that inhibits IL-23 signaling. Zasocitinib is under FDA review for moderate-to-severe plaque psoriasis with a decision expected early next year.
Meanwhile, Ascletis Pharma is advancing an investigational oral IL-17 inhibitor called ASC50 for psoriasis. Phase 1 data presented in December 2025 showed strong target engagement, painting what CEO Jinzi Jason Wu claimed is a “best-in-class” profile.
But even as pills start entering the market, “Skyrizi’s continued growth is pushing back on the idea that oral drugs will inevitably displace injectable biologics,” Kapoor said. “Patients continue to choose injections because infrequent dosing can actually be more convenient than taking a pill every day.” This is especially true for patients with controlled disease, he noted, who want to think about their conditions “as little as possible.”
Oruka Therapeutics is pushing this particular hypothesis to a “logical extreme,” he continued, with its injectable IL-23 inhibitor ORKA-001 that could potentially be dosed once a year, according to the biotech. The asset set to enter Phase 3 development in the first half of 2027.
