- Sudo Biosciences, a drug startup working to develop so-called TYK2 inhibitors for inflammatory diseases, has raised $37 million in Series A funding.
- The Menlo Park, Calif. company, which was founded in 2020, has four TYK2-targeting drugs in preclinical development for disorders such as psoriasis, psoriatic arthritis and lupus. The new funds, from Frazier Life Sciences and Velosity Capital, will help bring its most advanced prospects into human testing.
- TYK2 inhibitors, which target an enzyme involved in inflammation, have captured the attention of scientists and investors, offering a new way to treat autoimmune diseases. That interest is likely to grow further following the U.S. approval of Bristol Myers Squibb’s Sotyktu — the first drug of this type to reach the market, but a medicine that startups like Sudo claim they may be able to top.
September has been a busy month for developers of TYK2-targeting drugs.
First, the Food and Drug Administration cleared Sotyktu with a clean label, opting against putting strict warnings around its use or requiring patients try other medicines first.
That decision answered a question that had hung over TYK2 inhibitors, which target a protein related to the Janus kinases blocked by drugs like Xeljanz, Rinvoq and Olumiant. Those medicines have been linked to serious heart problems and cancer, so the FDA’s decision to consider Sotyktu apart boosted the prospects of others like it.
Since the FDA’s approval, two companies developing newer TYK2 blockers — Nimbus Therapeutics and now Sudo — have drawn in fresh funds from venture investors. Another developer, publicly traded biotechnology company Ventyx Biosciences, raised $177 million after its share price surged more than 60% on the Sotyktu news. Sudo, which has operated in stealth for the past two years, says they’re all buoyed by heightened interest in TYK2 inhibitors.
“I don’t think there’s any question the level of interest with investors has gone up,” said Scott Byrd, Sudo’s CEO, in an interview. “The confidence is growing that not only is there a huge class, but there's an opportunity to improve on it. ”
Though Sudo did not disclose specifics around its four research programs or say when human testing will begin, the company is targeting many of the same diseases as its competitors, such as psoriatic arthritis and lupus. It eventually plans to expand testing to include other conditions like Crohn’s disease or ankylosing spondylitis.
Sudo faces competition from both fellow startups and larger biotechs. Nimbus, for instance, has been developing a TYK2 blocker for years and is using its latest round to prepare for late-stage trials. Alumis, a startup formerly known as Esker Therapeutics, has raised $300 million to advance a TYK2 program. Ventyx, which went public in 2021, recently announced results from a Phase 1 trial and plans to start mid-stage testing later this year.
Established pharmaceutical companies are also developing TYK2 inhibitors. Galapagos is expecting to start a Phase 2 trial in dermatomyositis by the end of 2022. Pfizer was developing its own until last year, when it spun out two experimental TYK2 inhibitors into a new company named Priovant Therapeutics.
Still, Byrd says his company is confident it can hold its own. The biotech claims to be developing “precision” TYK2 medicines, but didn’t provide details.
“There are some ways to create fit-for-purpose programs that we think will allow us to compete very effectively and in innovative ways with those that are both on the market and developing products,” Byrd said.
That includes designing drugs Byrd says can compete with Sotyktu, offering “opportunity for greater efficacy” without increasing the risk of adverse effects, he said.