In a milestone for the next wave of AI-focused biotechs, Generate:Biomedicines is headed to Phase 3.
The Somerville, MA-headquartered biotech said Monday it is launching two large studies for its lead drug candidate, which is an anti-TSLP antibody called GB-0895, in severe asthma. It appears set to be the first Phase 3 start for an AI-focused biotech, a sign that the field is maturing beyond not just building models but advancing drug programs.
But the advancement is not without caveats. GB-0895 is not a
de novo
antibody, but the result of an optimization campaign that looked for the best tweaks to make to Amgen’s Tezspire, a TSLP antibody that has turned into a blockbuster since its 2021 approval.
Founded in 2018 out of Flagship Pioneering, Generate has grown into one of the largest AI-focused biotechs, with 310 employees and roughly $700 million in capital raised. CEO Mike Nally told
Endpoints News
that it has about $240 million in cash and hasn’t sought to raise since a $273 million Series C in 2023.
Generate also said IND filings are imminent for two oncology programs. The biotech also has an IL-13 antibody called GB-7624
in a Phase 1 study
that started earlier this year. Those programs also use its “generative optimization stack” to improve a starting molecule, rather than begin as
de novo
proteins.
While it has
published on its
de novo
design efforts
— a red-hot research area in 2025 — GB-0895 was first synthesized back in 2021, Nally said, before transformer and diffusion models swept through protein design.
The initial goal was to see if they could make an antibody that was five-fold better at binding to TSLP than Tezspire, and also extend the drug’s half-life. The idea was to stretch dosing to once every three months, from monthly.
Relying on earlier computational methods, it changed about 20% of the binding region, or the antibody’s CDRs, which recognize and bind to a target protein. Traditional optimization methods can typically change by up to 10%, Nally said, effectively allowing Generate to consider more possibilities.
“These techniques allowed you to change more of that binding interface to get to that optimal answer,” Nally said. “I don’t think you could have done this using historical techniques and search that space as effectively.”
The lab results wound up showing a 20-fold improvement in binding. Nally called it a 100-femtomolar binder, with a femtomolar being 1,000 times smaller than a nanomolar, a common scale in measuring drug binders. That opened up the early possibility of dosing every six months, double their target, as the dosing regimen they’ll now test in Phase 3.
GB-0895 started Phase 1 testing two years ago in mild to moderate asthmatics. Generate
presented interim results in September
at a European medical conference, saying the data supported a six-month dosing regimen.
“We’re now going into Phase 3 after just about four years,” said Laurie Lee, a GSK and CSL Behring veteran who joined the biotech in September as chief medical officer of its immunology and inflammation portfolio. “Without generative AI, we would be going into Phase 1 at this time.”
They’ve done so in part by skipping over Phase 2, which drugmakers often use to lock in an optimal dose for pivotal studies and to check safety. Instead, the biotech’s leaders are confident that the Phase 1 data are sufficient to choose a 300 mg dose every six months. (Larger doses, going up to 1,200 mg, didn’t show much added benefit.)
The start of Phase 3 put Generate in the lead as a would-be challenger to Tezspire. Pfizer, Sanofi, GSK, Johnson & Johnson, and Upstream Bio all have clinical-stage TSLP-targeting programs — some as standalone antibodies, others as part of bispecifics or trispecifics — but none has started Phase 3. AstraZeneca has also said it is in the early research stages on a potential inhaled TSLP molecule.
“I’m sure there are a number of very viable competitors,” Nally said. “At the same time, we believe we will be the first long-acting anti-TSLP to market by somewhere between 12 and 18 months.” If all goes to plan, Generate intends to file for approval in 2029, Nally said.