AnaptysBio is splitting itself in two — and betting that Wall Street will value each half more than the sum of the whole.
The San Diego biotech announced Thursday that its board has approved a spin-off of First Tracks Biotherapeutics, a clinical-stage immunology company that will begin regular-way trading on Nasdaq under the ticker TRAX on April 20, 2026, according to a Globenewswire release. First Tracks launches with $180 million in cash: $100 million contributed by Anaptys, plus an $80 million private placement that brought in a syndicate of institutional investors including Point72, Janus Henderson, Adage Capital Partners, Ally Bridge, Palo Alto Investors, TCGX, and Woodline Partners, among 13 institutions total, according to the Manila Times. EcoR1 Capital, a known Anaptys shareholder, receives $65 million of the PIPE proceeds — a sizable position that reflects a bet that First Tracks is worth building.
Daniel Faga, Anaptys' president and CEO since 2022, will run both companies post-spin: president and CEO of First Tracks, and CEO of the remaining Anaptys entity, according to an AnaptysBio press release. Ajim Tamboli, who brings over 25 years of life sciences experience as an investor, equity research analyst, and CFO at public and private biotechs, joins as CFO of First Tracks. Susannah Gray, who spent 14 years as CFO of Royalty Pharma before retiring in 2019, joins the Anaptys board.
The structure Anaptys is left with after the spin-off is unusual in biotech — and unusually clean. Post-separation, Anaptys will operate with fewer than 10 full-time contractors, annual operating expenses under $10 million, and an EBIT margin projected above 95%. There are no employees in the conventional sense, no labs to maintain, no clinical trials to run. The entire economic model rests on Jemperli, a PD-1 inhibitor licensed to GSK that is growing at a clip that makes the royalty pharma comparison apt.
GSK reported $343 million in Q4 2025 sales for Jemperli, implying an annualized run rate above $1.4 billion — up more than 13% quarter-over-quarter in both USD and GBP. Anaptys received a $75 million commercial milestone payment in December 2025 when Jemperli crossed $1 billion in worldwide net sales, and the company expects to collect more than $390 million annually at GSK's peak sales guidance of above $2.7 billion, which GSK projects as early as 2029, according to an AnaptysBio press release. Anaptys ended 2025 with $311.6 million in cash and investments, down from $420.8 million at the end of 2024 — a decrease of $109.2 million primarily attributable to $130.6 million used for operating activities and $68.6 million in share repurchases, partially offset by $75 million received from GSK and $15 million received from Vanda Pharmaceuticals. The cash position gives the royalty vehicle real durability even without additional milestones. The company also announced a $100 million stock repurchase plan.
First Tracks, by contrast, carries the clinical risk — and the upside. The company lists three assets: Rosnilimab, a Tph cell-depleting antibody that completed Phase 2b for rheumatoid arthritis and is in a separate Phase 2 trial for ulcerative colitis; ANB033, a CD122 antagonist entering Phase 1b for celiac disease; and imsidolimab, an anti-IL-36R antibody whose biologics license application for generalized pustular psoriasis was accepted by the FDA in February 2026 with a target action date of December 12, 2026.
Rosnilimab is the most clinically advanced and the most interesting structurally. According to AnaptysBio Phase 2b trial results, the Phase 2b RENOIR trial enrolled 424 patients with rheumatoid arthritis. By Week 6, Tph cells — a population of pathogenic memory T cells implicated in rheumatoid arthritis activity — were reduced more than 90% in peripheral blood across all dose cohorts, and in the synovium at the two highest doses. The 38-week safety readout showed no malignancies in the treatment period, and a durable off-drug signal that will need to be confirmed in Phase 3 but is notable given the class risk profile. Tph cell depletion as a mechanism has generated significant interest in autoimmune indications; the durability signal suggests the effect may outlast the dosing window, which would matter substantially for a rheumatoid arthritis therapy given the chronic nature of the disease and the burden of continuous dosing. Separately, rosnilimab failed a Phase 2 trial in ulcerative colitis in November 2025, with 7% clinical remission at Week 12 versus placebo — not statistically different from placebo.
ANB033 is the near-term catalyst. Phase 1b celiac disease top-line data is anticipated in Q4 2026, with an eosinophilic esophagitis Phase 1b trial initiated in Q1 2026 and top-line data expected in 2027. CD122 — the IL-2 receptor beta subunit — is a different mechanism than CD40-CD40L costimulation blockade; the target has been of interest in autoimmune GI disease and the bispecific landscape has made it a more crowded space — First Tracks will need to show a clean safety profile and meaningful histological signals to stand out. The celiac indication is commercially attractive: no approved therapies that address the underlying immunology exist today.
The PIPE syndicate is worth dwelling on. Point72, Janus Henderson, and Adage Capital Partners are not casual biotech investors. Adage in particular has a track record of taking concentrated positions in situations where the public market undervalues a royalty stream or a pipeline split. The fact that 13 institutions participated suggests institutional demand for the TRAX ticker was real — not a bridge financing or a compromise deal, but a genuine market test that came in clean.
AnaptysBio has been an odd duck in the biotech landscape for years: a clinical-stage company with a royalty business bolted onto it, generating confusion about what kind of company it was and what metric mattered. The spin-off resolves that ambiguity, for better and for worse. Anaptys post-spin is not a biotech company in any meaningful sense — it is a lottery ticket attached to GSK's commercial execution. First Tracks is the opposite: a well-funded, clearly-structured clinical-stage bet with a notable safety signal in a competitive but high-value indication.
Faga runs both. That is not without tension: the incentive structures of a royalty company and a clinical-stage biotech are fundamentally different, and the board composition and governance of each entity will matter for how conflicts are managed. Royalty companies do not need to run clinical trials. Clinical-stage companies cannot avoid it. Whether Faga's attention splits productively or dangerously is a question worth asking — and one that neither Anaptys nor First Tracks filings will answer directly.
The broader question is whether the public market has appetite for a pure-play immunology royalty company in an era when investors have largely soured on "pipeline in a product" stories. Anaptys' >95% EBIT margin and sub-$10 million OpEx are genuinely unusual numbers — they describe something closer to an intellectual property holding company than a biotech. If Jemperli continues to grow at its current rate, the Anaptys ticker becomes a synthetic royalty play that may trade on GSK's commercial execution rather than any internal science. That is a different risk profile than most biotech, and whether it deserves a premium or a discount to the underlying royalty stream is a question the April 20 listing will begin to answer.
First Tracks, meanwhile, has the capital to run Phase 3 preparations for Rosnilimab without immediate dilution pressure — $180 million is a meaningful war chest for a Phase 2b company, but not a comfortable one if a rheumatoid arthritis Phase 3 program costs $200 million or more. The PIPE math implies a valuation that the market will either accept or revisit. Either way, TRAX will be a ticker worth watching once it starts trading.