The flurry of immunology biotech launches continues.
Boston-based Hillstar Bio on Tuesday became the latest immunology startup launch, unveiling a $67 million Series A round funded by Droia Ventures, Frazier Life Sciences, Novo Holdings and LifeArc Ventures.
The biologics developer has been in the works since 2023, CEO Robert Mabry told
Endpoints News
. Mabry joined Hillstar in recent months after departing his chief scientific officer post at RNA medicines outfit
Orna Therapeutics
.
“It’s just such a fantastic time for biologics right now. You’re seeing just a renaissance. All the technology is coming to fruition,” Mabry said.
With the Series A, Hillstar expects to get into the clinic next year with its first biologic. The startup will begin in axial spondyloarthritis, or axSpA. The inflammatory condition leads to lower back pain, causing arthritis in the spine and other joints and organs. Approved medicines for the condition include Novartis’
Cosentyx,
UCB’s
Bimzelx
and AbbVie’s
Rinvoq
. Others, like Acelyrin, once
had ambitions
in the space.
Hillstar’s HSB-101 biologic targets TRBV9
+
T cells. The goal is to invoke an “immune reset,” Mabry said.
Beyond its lead asset, Hillstar could go into cold agglutinin disease, or CAD, according to a job posting for the company. In the rare condition, a patient’s immune system prematurely kills red blood cells. Sanofi sold Enjaymo, its approved drug for the condition,
to Recordati for $825 million
in October.
“It’s still an area that we’re exploring,” Mabry said of CAD. “What we’ve been able to generate is a proprietary dataset using patient samples in that area, so we’re very excited about that as one of many different autoimmune diseases that we can go after.”
Leading the biotech’s development is former Boston Pharmaceuticals clinical development SVP Mitchell Keegan. Hillstar’s chief operating officer is Lauren Mifflin, a principal of company creation at one of the startup’s key investors, Frazier Life Sciences.
Hillstar’s board includes Mabry, Ingram, Novo Holdings senior partner Kenneth Harrison, Frazier General Partner Dan Estes, Droia Managing Partner Luc Dochez and Droia Partner Matthias Van Woensel.
Mabry emphasized that the startup is an asset-focused company with drugs near the clinic — a profile investors have favored over the last few years of a moribund biotech sector.
“We’re an asset company, a pipeline company — we’re not a platform technology company,” Mabry said. “That really changes the way you can run a biotech company. It changes the way you use the capital.”
Along with the investment funds, another key Hillstar backer is Hummingbird Bioscience, a Singapore-based biotech that originated about a decade ago and that has antibody and antibody-drug conjugate platforms. Earlier this month, Frazier and Novo Holdings backed an ADC spinout from Hummingbird called
Callio Therapeutics
.
“They’ve been a great shareholder for us and so being able to leverage them as part of our development, but also gaining access to other technologies that provide a lot of insight into development, that’s been a great partnership for us,” Mabry said of Hummingbird.