Bluejay Therapeutics Acquisition, Valuation, Funding & Investors

Bluejay Therapeutics was acquired by Mirum Pharmaceuticals for $820M in December 2025.

Bluejay Therapeutics acquisition price

$820M

Acquired by Mirum Pharmaceuticals · Dec 2025

Cumulative funding Bluejay Therapeutics raised

$242M

across 3 funding rounds

Key investors in Bluejay Therapeutics

Bluejay Therapeutics Overview

About Bluejay Therapeutics

Bluejay Therapeutics is a New York-based biopharmaceutical company. The firm develops therapies for chronic Hepatitis B using fully human anti-HBs monoclonal antibodies and oral HBsAg inhibitors. Bluejay Therapeutics advances clinical candidates toward functional cures for infectious diseases.


Founded

2019

HQ

United StatesSan Francisco, CA

Status

Acquired

Customer focus

B2B

Revenue model

Product sales

Valuation

$820M (acquired Dec 2025)

Bluejay Therapeutics Acquisition

Bluejay Therapeutics was acquired by Mirum Pharmaceuticals for $820M on 8 December 2025.

Before the acquisition Bluejay Therapeutics had raised $242M across 3 funding rounds.

Bluejay Therapeutics, a privately held biotechnology company focused on viral and liver diseases, developed brelovitug, a late-stage fully human monoclonal antibody targeting the surface antigen of chronic hepatitis delta virus (HDV) and hepatitis B virus (HBV). HDV, a severe coinfection with hepatitis B affecting 230,000 people in the US and Europe, lacks approved therapies in the US. Brelovitug has received FDA Breakthrough Therapy and Orphan designations, plus EMA PRIME designation, and is in the global AZURE Phase 3 registrational program evaluating biochemical and virologic responses for potential BLA submission and launch in 2027. Mirum Pharmaceuticals, a rare disease company marketing LIVMARLI for chronic itching due to Alagille syndrome and advancing volixibat, completed the acquisition of Bluejay in early 2026 after announcing a definitive agreement on December 8, 2025. The deal provides Mirum worldwide rights to brelovitug, strengthening its rare liver disease pipeline and positioning it for first-mover advantage in HDV. Strategic rationale leverages Mirum's expertise in rare liver disorders, provider relationships, and global development-commercial synergies to advance the asset through Phase 3 completion, regulatory filings, and launches. Deal terms include $250 million cash and $370 million in Mirum common stock (priced at $71.21 per share) for all Bluejay shares, plus up to $200 million in tiered sales-based milestones, valuing the upfront at $620 million and total potential at $820 million. Concurrently, Mirum raised approximately $268.5 million (initially targeted at $200 million) via private placement to existing and new healthcare investors to fund brelovitug's clinical development and commercialization. The transaction, approved by both boards, closed subject to regulatory approvals and customary conditions.

Bluejay Therapeutics acquisition details
AcquirerDateTypePrice
8 Dec 2025Strategic M&A$820M

Bluejay Therapeutics Funding History

Bluejay Therapeutics has raised a total of $242M across 3 funding rounds.

Bluejay Therapeutics' first fundraising round was a $19M undisclosed-stage round in June 2021. The most recent completed round was a $182M Series C in May 2024.

Bluejay Therapeutics funding rounds

Bluejay Therapeutics funding rounds
DateStageInvestorsRaisedDeal Summary
May 2024Series CFrazier Life Sciences (lead); Wellington Management; Novo Holdings; HBM Healthcare Investments; T. Rowe Price; Octagon Capital Advisors; RiverVest; Arkin Bio Ventures; RA Capital Management; Unicorn Capital Partners$182MBluejay Therapeutics closed a $182 million Series C financing in May 2024, co-led by Frazier Life Sciences and another life science institutional investor. Participants included RA Capital Management, T. Rowe Price, Wellington Management, Novo Holdings, RiverVest Venture Partners, Octagon Capital, Arkin Bio Ventures, HBM Healthcare Investments and Unicorn Capital Partners. The proceeds are to accelerate clinical development of BJT-778 and advance other pipeline candidates. Founder and CEO Keting Chu said the round reflected investor confidence in the company's strategy and team, and Daniel Estes of Frazier joined the board after the financing. Bluejay is based in San Mateo, California, and develops therapeutics for chronic hepatitis D and hepatitis B. Its lead candidate, BJT-778, received PRIME designation from the European Medicines Agency based on Phase 1/2 results in hepatitis D. The company is also advancing hepatitis B programs, including the TLR9 agonist cavrotolimod and the liver-targeted transcript inhibitor BJT-628, aiming for higher functional cure rates.
Aug 2022Series BArkin Bio Ventures (lead); Yonjin Venture; Octagon Capital Advisors; RiverVest; Synergenics$41MBluejay Therapeutics closed a $41 million Series B funding round on August 16, 2022, led by Arkin Bio Ventures with participation from Synergenics LLC, RiverVest Venture Partners, Yonjin Capital, Octagon Capital, and InnoPinnacle International. The company is a virology and liver disease-focused biotechnology firm developing treatments for chronic hepatitis B virus infection. Bluejay's pipeline includes two programs: BJT-778, a human anti-HBsAg monoclonal antibody, and BJT-574, an orally bioavailable small molecule HBsAg inhibitor. Both programs were licensed from Novartis and were in advanced preclinical stages at the time of the Series B. The funding was designated to support clinical development of the lead program BJT-778 to demonstrate proof-of-concept in chronic HBV patients, as well as advancement of BJT-574 into first-in-human clinical trials. Founder and CEO Keting Chu, who previously led biotech startups and worked as a venture partner at Silicon Valley VC firms, launched Bluejay in 2019 after raising a $20 million Series A in 2020. The company was positioned within a competitive landscape that included Arrowhead Pharmaceuticals, Dicerna Pharmaceuticals, Vir Biotechnology, and Arbutus Biopharma, most of which were already in clinical trials with partnerships from major pharmaceutical companies including Johnson & Johnson and Roche.
Jun 2021Undisclosed stage-$19MThe company later raised additional rounds, including a Series B on August 16, 2022, and a Series C for $182M on May 9, 2024, led by investors such as Frazier Life Sciences, RA Capital Management, T. Rowe Price, and others. Total funding across rounds reached approximately $242M by 2025. Bluejay's lead candidate BJT-778 (now brelovitug), a monoclonal antibody against hepatitis B surface antigen, received PRIME designation from the EMA and advanced to Phase 3 trials for HDV. The company focused on unmet needs in HDV, a severe condition lacking U.S. approvals, positioning brelovitug as a potential first-in-class therapy. Bluejay was acquired by Mirum Pharmaceuticals in December 2025 for $268.6M in cash and stock plus milestones, adding brelovitug's late-stage HDV program to Mirum's rare liver disease portfolio. Post-2021, Bluejay demonstrated capital efficiency with a 3.37x ratio relative to total capital raised by late 2025, when secondary market valuations reached $820M ahead of acquisition.

Who has invested in Bluejay Therapeutics?

12 investors have backed Bluejay Therapeutics across its funding rounds, including RiverVest, Octagon Capital Advisors, Arkin Bio Ventures, RA Capital Management, T. Rowe Price and Novo Holdings.

Lead investors include Frazier Life Sciences and Arkin Bio Ventures.


Bluejay Therapeutics Investors

Investors in Bluejay Therapeutics by funding rounds participated
InvestorHQRoundsRoleFirst check
Octagon Capital AdvisorsUnited StatesNew York City, NY2ParticipantAug 2022
RiverVestUnited StatesUnited States2ParticipantAug 2022
Arkin Bio VenturesIsraelHerzliya2LeadAug 2022
Wellington ManagementUnited StatesBoston, MA1ParticipantMay 2024
Novo HoldingsDenmarkCopenhagen1ParticipantMay 2024
HBM Healthcare InvestmentsSwitzerlandZug1ParticipantMay 2024
Yonjin VentureUnited StatesUnited States1ParticipantAug 2022
T. Rowe PriceUnited StatesBaltimore, MD1ParticipantMay 2024
Frazier Life SciencesUnited StatesSan Francisco, CA1LeadMay 2024
RA Capital ManagementUnited StatesBoston, MA1ParticipantMay 2024

This data is available for Pro users. Sign up to see all 12 Bluejay Therapeutics investors.

Start Free Trial

Benchmark 350K+ Funding Rounds and Disclosed VC Valuation Multiples

Sign up to see data on 350K+ funding rounds and disclosed revenue and EBITDA valuation multiples, from seed, through growth stage, to pre-IPO.

Start Free Trial

Bluejay Therapeutics Competitors

Bluejay Therapeutics competitors include listed companies like Kolon TissueGene, Keqian Biology, Latigo Biotherapeutics and Sanofi India, and private ones like Huisheng Biopharmaceutical and Stramsen Biotech.

Public and private companies comparable to Bluejay Therapeutics
CompanyHQStatusRevenueEBITDAValuationRevenue Multiple
Kolon TissueGeneUnited StatesUnited StatesPublicly listed$4M($143M)$821M229.0x
Keqian BiologyChinaChinaPublicly listed$143M$81M$814M4.1x
Huisheng BiopharmaceuticalChinaJilinPrivate--$809M-
Stramsen BiotechUnited StatesUnited StatesPrivate--$807M-
Latigo BiotherapeuticsUnited StatesUnited StatesPublicly listed-($112M)$835M-
Sanofi IndiaIndiaIndiaPublicly listed$194M$50M$804M3.8x

Bluejay Therapeutics Public Comps

Bluejay Therapeutics is no longer listed, but its public comps include Kolon TissueGene, Keqian Biology, Latigo Biotherapeutics, Sanofi India, Sanofi Consumer Healthcare India, Knight Therapeutics, Prime Medicine, Annexon, Suven Life Sciences and PeptiDream.

Last FYEV/RevenueEV/EBITDA
RevenueEBITDALast FYLTM2027ELast FYLTM2027E
Kolon TissueGene$4M($143M)209.0x229.0x(5.6x)(56.3x)
Keqian Biology$143M$81M3.9x4.1x6.8x8.5x
Latigo Biotherapeutics-($112M)--(3.9x)-
Sanofi India$194M$50M3.9x3.8x15.3x13.3x
Sanofi Consumer Healthcare India$93M$34M8.4x7.5x23.3x20.0x
Knight Therapeutics$321M$39M2.2x1.9x18.6x11.5x
Prime Medicine$5M($198M)182.1x98.4x(4.3x)(4.9x)
Annexon-($214M)--(2.9x)(2.7x)

This data is available for Pro users. Sign up to see all Bluejay Therapeutics competitors and their valuation data.

Start Free Trial

Common questions about Bluejay Therapeutics

When was Bluejay Therapeutics founded?Bluejay Therapeutics was founded in 2019.
Where is Bluejay Therapeutics headquartered?Bluejay Therapeutics is headquartered in San Francisco, CA, United States.
Is Bluejay Therapeutics publicly listed?No, Bluejay Therapeutics was acquired by Mirum Pharmaceuticals in December 2025.
Who acquired Bluejay Therapeutics?Bluejay Therapeutics was acquired by Mirum Pharmaceuticals in December 2025.
How much was Bluejay Therapeutics acquired for?Bluejay Therapeutics was acquired for $820M in December 2025.
How much funding has Bluejay Therapeutics raised?Bluejay Therapeutics has raised $242M across 3 funding rounds.
What was Bluejay Therapeutics' last funding round?Bluejay Therapeutics' last funding round was a $182M Series C in May 2024, led by Frazier Life Sciences.
Who are Bluejay Therapeutics' investors?Bluejay Therapeutics' investors include Octagon Capital Advisors, RiverVest, Arkin Bio Ventures, Wellington Management, Novo Holdings, HBM Healthcare Investments, Yonjin Venture, T. Rowe Price, Frazier Life Sciences, RA Capital Management and 2 others.
Which companies are comparable to Bluejay Therapeutics?Companies comparable to Bluejay Therapeutics include Kolon TissueGene, Keqian Biology, Huisheng Biopharmaceutical, Stramsen Biotech, Latigo Biotherapeutics and Sanofi India.

See companies similar to Bluejay Therapeutics

Start Your
Free Trial Today

Try Multiples for free for 3 days. Got questions or need a demo? Schedule a call with us below.

Start Trial