AnaptysBio (NASDAQ:ANAB) CEO Daniel Faga outlined progress on the company’s planned separation into two entities, provided an update on its royalty streams and ongoing litigation related to GSK’s Jemperli, and discussed the clinical and commercial rationale for the biopharma assets that will be spun into a new company, First Tracks Bio (expected ticker: FSTX), during a recent investor event hosted by David Risinger.
Plan to separate into a royalty company and a spun-out biopharma business
Faga said Anaptys announced roughly six months ago that it intended to “break the company into two,” and he described the separation as nearing completion. He said the company filed a Form 10 “last week” and that the separation could occur in “approximately 45 days,” with a target of the end of April, describing that timing as both the “best case scenario” and the company’s “base case.”
He emphasized that the separation is not dependent on the outcome or timing of the company’s litigation with GSK, noting that Anaptys announced the intent to separate “long before the litigation existed.” He also said “effectively all our employees will be transitioning over to First Tracks Bio.”
Jemperli royalty outlook and key upcoming catalysts
Faga said the parent company will retain two royalty streams: Jemperli, described as a commercial oncology program sold to GSK, and imsidolimab, which he said has a PDUFA date in mid-to-late December of this year and will be sold by Vanda. He said the company expects to exit the year with “two commercial royalties.”
On Jemperli, Faga said he continues to see “quarter-over-quarter excitement” in the U.S. endometrial cancer launch, with more recent momentum in Europe and continued European expansion expected this year. He said Jemperli “ended on a $1.4 billion run rate,” and noted that GSK has guided to peak sales “far north of” $2.7 billion. He characterized current growth as “mid-teens%, quarter-over-quarter.”
Faga also pointed to potential catalysts later this year, including “pivotal data in rectal cancer” that GSK has guided to release later in 2026, and said GSK received a priority voucher that could enable rolling submissions and an “approval timeframe” of one to two months. He said it is conceivable Jemperli could be approved in a second indication in dMMR rectal cancer, where he said Keytruda “is not even present.”
Royalty economics and parent-company cost structure
Faga described what he called an “outsized royalty” on Jemperli, stating it is 8% at $1 billion in sales and escalates up to 25% above $2.5 billion. He said Anaptys generated about $100 million in royalties last year, and that this year could be “closer to $200 million.” At what he described as peak—potentially “as soon as 2029”—he said royalties could approach $400 million if GSK achieves $2.7 billion in sales.
He also said the parent company could become cash-flow positive as early as mid-2027 after paying down non-recourse debt that remains outstanding. Operationally, he described the remaining royalty company as requiring limited infrastructure—“less than $10 million of OpEx” and “less than 10 FTEs”—and said it would be “generally speaking, a virtual company.”
Update on litigation with GSK
Faga said the ongoing litigation relates to what Anaptys views as contractual breaches regarding how GSK is developing its oncology portfolio in combination with PD-1 antagonists. He said GSK is evaluating combinations of its antibody-drug conjugates (ADCs) not only with Jemperli, but also with Keytruda, and that Anaptys believes this violates contractual provisions related to exclusivity and disclosures, as well as a “CRE obligation.”
He characterized the CRE obligation as a high bar requiring “optimum commercial return” for Jemperli, and argued that spending to develop or commercialize competitor combinations could come “at the expense of Jemperli.” Faga said Anaptys has three different claims and that, if it wins on any of them, the contract states Jemperli would revert to AnaptysBio.
Faga also said GSK filed a counterclaim that initiated the public litigation and that a hearing was held last week regarding Anaptys’ motion to dismiss. He said a decision on that motion is expected within 60 days of the hearing. He added that the trial for Anaptys’ claims is scheduled for July 14 as a bench trial in the Delaware Chancery Court.
First Tracks Bio: ANB033 in celiac disease and eosinophilic esophagitis
Turning to the spun-out biopharma business, Faga described ANB033 as the “anchor” program, with initial focus on celiac disease and eosinophilic esophagitis (EoE). He said celiac disease has no approved therapies for patients who are not controlled on a gluten-free diet, and cited an estimate of 250,000 diagnosed U.S. patients not controlled by diet.
Faga described ANB033 as a CD122 antagonist intended to block IL-15 and IL-2 signaling. He said differentiation includes subcutaneous administration and potency, citing phase 1a data in healthy individuals that, at a mid-dose single ascending dose, eliminated 98% of CD122-expressing NK cells in the periphery and reduced CD8 CD122-expressing cells in the “mid-70%” range.
For the phase 1b celiac study, he said the trial enrolls 60 patients split into two 30-patient cohorts, randomized 1:1 (15 drug, 15 placebo per cohort). He described one cohort as a gluten-challenge design with biopsy at week six, and a second cohort that includes patients with baseline mucosal injury (VHCD ratio less than two), with biopsies at week 12 to assess healing after dosing at weeks 0, 2, and 4. Faga said the company expects data across both cohorts in the fourth quarter of this year and stated enrollment began in Australia and New Zealand, with expansion into Europe and later the U.S., adding that timelines remain on track.
On safety, Faga said the company has not observed infections or other safety issues in phase 1a to date and said the broader IL-15/CD122 class has not shown major issues so far, citing Teva’s long-term data as supportive of durability without observed safety problems.
In EoE, Faga cited proof-of-concept data from CALY-002 (an IL-15 program acquired by Novartis) showing that blocking IL-15–driven CD8 activity can prevent recruitment of eosinophils. He noted Dupixent is currently the only approved EoE therapy and said the addressable U.S. biologic-eligible population is about 175,000 patients. He discussed a hypothesis that IL-15 may correlate with lack of response in a subset of Dupixent-treated patients and argued CD122 blockade could potentially address both Th2/ILC2-driven and CD8-driven pathways. He said First Tracks expects EoE data in 2027.
Faga also said the company is evaluating additional indications beyond celiac and EoE, aiming—depending on capital allocation—to progress toward multiple phase 2b programs by 2027–2028, while noting that the amount of cash allocated to First Tracks will be disclosed once the Form 10 becomes effective.
About AnaptysBio (NASDAQ:ANAB)
AnaptysBio, Inc is a clinical-stage biotechnology company focused on the discovery and development of therapeutic antibody product candidates in immunology and inflammation. Founded in 2012 and headquartered in San Diego, California, AnaptysBio leverages a proprietary somatic hypermutation platform to rapidly generate and refine human antibodies with optimized efficacy and safety profiles. The company’s technology is designed to accelerate target validation and candidate selection across a range of immune-mediated conditions.
The company’s pipeline includes multiple clinical-stage programs addressing dermatological and inflammatory disorders.
