With an IPO raise of $625 million, Kailera Therapeutics now holds the new record for the largest public market debut.
Biopharma opened the gates to the public markets in 1980—and first to go through was Genentech.
The company offered 1 million of its stock for sale at $35 apiece, an initial public offering (IPO) that The Wall Street Journal said at the time was “one of the most spectacular market debuts in recent history.” Genentech held a second IPO in 1999—re-entering the market after major shareholder Roche refloated a huge chunk of the company—amassing nearly $2 billion in proceeds.
After setting the IPO standard for the industry, Genentech has gone on to become one of the most successful biotechs of all time, now best known as the core component of Roche’s drug development engine.
A multi-billion biotech today seems impossible, as the pipeline to the public markets has slowed to a trickle.
This is especially true in the post-pandemic era, as the industry rightsizes following the influx of investments driven by the COVID-19 emergency. Last year, only eight biotechs braved the IPO waters—the lowest in at least five years.
But change seems to be in the cards this year. The IPO market has shown encouraging signs of recovery: just in the first quarter of 2026, 10 companies went public or have commenced offerings, already eclipsing the 2025 class. And while a couple of these raises have broken years-long records—Eikon Therapeutics’ $380 million plan, for instance, and Generate:Biomedicines’ $400 million offering—none have excited industry observers more than Kailera Therapeutics.
Massachusetts-based Kailera burst onto the scene in October 2024 with a massive $400 million series A and a clutch of China-derived assets for obesity. Earlier this month, Kailera launched its bid for the Nasdaq Global Select Market, aiming to raise up to $533 million.
The biotech went well over that mark, clocking the largest IPO in biopharma’s history. Here, BioSpace looks at the other record-smashers—the biotechs that have brought in staggering amounts of money in their IPOs—and where they are now.
1. Kailera Therapeutics
IPO Date: April 2026
IPO Value: $625 million
Kailera put up more than 39 million shares of its common stock up for sale for $16 a pop. This pricing would give the biotech $625 million in gross proceeds—surpassing some of the industry’s most prominent players, including Moderna ($604 million), Johnson & Johnson’s cancer collaborator Legend Biotech ($487.3 million) and fellow obesity star Metsera ($316.2 million).
It’s no surprise that obesity-focused Kailera would top the all-time IPO leaderboard. The industry, after all, has been pumping staggering amounts of money into the weight-loss market. Just in the first quarter of this year, biopharma has committed up to $22 billion in obesity and diabetes licensing deals, inclusive of milestones, according to an analysis by J.P. Morgan. This amount already exceeds the total deal value pledged in all of 2025 and doesn’t yet take acquisitions into account.
Estimates vary, but a separate J.P. Morgan report forecasts the obesity market to hit $200 billion in value by 2030.
Kailera’s pipeline is led by ribupatide, a dual agonist of the GLP-1 and GIP receptors that the biotech got from Jiangsu Hengrui Pharmaceuticals. An oral and injectable formulation of ribupatide is in the works.
Phase 2 data released in February showed 12.1% weight reduction at 25 weeks in patients treated with 25-mg or 50-mg ribupatide, whereas placebo comparators hit only 2.3% weight loss at this time point. These findings encouraged Kailera and Hengrui to push injectable ribupatide into Phase 3 development.
Kailera has earmarked $625 million for injectable ribupatide, which is currently in three Phase 3 studies, according to an April 13 securities filing. The pill form of ribupatide will get around $150 million, which will help bankroll a late-stage study set to start as early as the first half of 2027.
Aside from ribupatide, Kailera is also working on a daily GLP-1 pill KAI-7535, which will get $50 million to power a Phase 2 study.
2. Moderna
IPO Date: December 2018
IPO Value: $604.35 million
Even before exploding into the public’s consciousness during the COVID-19 pandemic, Moderna was a buzzy biotech, commanding attention and interest from investors almost as soon as it was founded in 2010.
Moderna attracted hefty sums of money, including a $450 fundraise in 2015 and a $500 million round in February 2018, which put the biotech at a $7 billion valuation, PitchBook reported, elevating it to be the most valuable company in Massachusetts at the time. Later that year, in December 2018, Moderna went public with a staggering $604 million raise and a market cap of $7.5 billion.
This IPO was record-breaking, easily eclipsing Allogene, which previously held the IPO crown with a $324 million Nasdaq debut. Allogene has now slipped to No. 12 on the list.
Moderna was able to take full advantage of the massive influx of money into biopharma during the coronavirus pandemic, leveraging its mRNA platform to develop a next-generation vaccine against the disease. Spikevax became the world’s third best-selling drug in 2021 with $17.7 billion in sales, according to an analysis by Fierce Pharma. That same year, Moderna reached its peak valuation of $167 billion.
But the post-COVID-19 market hasn’t been kind to Moderna, as leadership has struggled to parlay the pandemic success into another marketable product. Moderna’s net income and share price have been in freefall. As of writing, the biotech’s market cap has crashed to around $21 billion.
The challenges seem to keep coming for Moderna. In February, the FDA declined to even review the company’s flu vaccine, claiming that the application wasn’t backed by an adequate and well-controlled trial. This refusal, Moderna admitted, thwarted its plans to break even by 2028. The FDA later reversed course and decided to accept Moderna’s application with a decision set for August this year.
3. Sana Biotechnology
IPO Date: February 2021
IPO Value: $587.5 million
Cell engineering specialist Sana Biotechnology originally set its sights too low: The biotech first announced an intent to go public in January 2021, setting a fundraising target of $150 million. A few days later, bolstered by the interest in its business, Sana raised that goal to $323 million.
When Sana closed its IPO on Feb. 3, 2021, the final tally was $587.5 million.
Sana, which made the cut for BioSpace’s NextGen Class of 2021, is advancing a pipeline of cell therapies for diabetes and cancer. At the time of the IPO, the biotech pledged $380 million for its cell engineering platform, divided equally between in vivo and ex vivo technologies.
This investment started paying off in March this year, with first-in-human data showing that allogeneic islet cells were able to maintain insulin secretion for more than one year after transplantation. The investigational cell therapy, called UP421, is being studied by the Uppsala University Hospital in Sweden and was processed through Sana’s hypoimmune platform, which suppresses the immune response of transplant recipients and eliminates the need for immunosuppression.
These findings have emboldened Sana to double down on the preclinical cell therapy SC451, which uses the same hypoimmune technology to deliver stem cell-derived islet cells. A Phase 1 study in type 1 diabetes is planned for this year.
Sana has also run into some rough spots since the IPO. In November 2025, Sana deprioritized the development of two allogeneic CAR T assets—SC291 for B cell-mediated autoimmune disorders and SC262 for cancer—and funneled resources into SC451 and SG293, an in vivo CAR T therapy for which an investigational new drug application could come as early as 2027.
4. Acelyrin
IPO Date: May 2023
IPO Value: $540 million
When Acelyrin began its march toward Nasdaq in early 2023, biopharma was entering the second year of a post-pandemic slump, with funding streams starting to run dry after the torrent of money in 2020 and 2021. Acelyrin’s $540 million raise—which was not just one of the largest of that year but among the biggest in the industry’s history—was understandably met with much excitement and seen as a signal of the market’s recovery.
Much of the enthusiasm around Acelyrin centered around lead asset izokibep, an antibody mimetic that works by blocking IL-17A. This mechanism of action positioned izokibep as a potential therapy for a host of immune-driven disorders, such as hidradenitis suppurativa, psoriatic arthritis and uveitis.
Shortly after going public, however, izokipeb hit a losing streak that ultimately proved fatal. In September 2023, a Phase 2b/3 study in hidradenitis suppurativa found that the asset failed to elicit a higher clinical response than placebo. A few months later, Acelyrin uncovered dosing errors by a third-party contract researcher, forcing the biotech to conduct a sweeping review of its izokibep program.
In December 2024, izokibep again delivered a Phase 2b/3 disappointment, unable to elicit significant treatment benefits in patients with uveitis. Faced with another defeat, Acelyrin opted to discontinue izokibep.
A few months later, in February 2025, Acelyrin sought to exit by merging with fellow immune player Alumis in a deal that would give Acelyrin’s shareholders 45% of the resulting combined entity.
The move only attracted more controversy for Acelyrin. Shortly after announcing the merger, Kevin Tang’s cleanup company Concentra Biosciences sought to acquire Acelyrin—an offer that the biotech rejected and adopted a “poison-pill” defense against. A major Acelyrin shareholder, Trium Capital, also publicly denounced the proposed merger with Alumis, calling the deal one that is “substantially less than its cash value.”
Trium even pointed to the Tang offer as proof that Acelyrin is worth much more than what it would be getting from the Alumis merger.
The two immune biotechs pushed through, however, and closed their merger in May 2025.
5. Recursion
IPO Date: April 2021
IPO Value: $436.4 million
Capping off this list is Recursion, which went public in 2021 with a $436.4 million raise—marking one of the earliest instances of an AI-centric drug developer attracting a hefty sum from the life sciences investing community.
Instead of a biotech, Recursion, based in Salt Lake City, prefers to call itself a “TechBio” company—one that uses advanced AI models for its drug discovery and development engine, according to its website. The company relies on its proprietary Recursion Operating System platform, which guides target identification all the way through clinical trial enrollment.
Recursion is leveraging this approach to advance novel therapies for various indications, with a particular focus on cancer and rare diseases. The lead asset is REC-4881, an oral small-molecule blocker of the MEK1 and MEK2 proteins being tested for familial adenomatous polyposis, a rare disorder that predisposes patients to cancer. Recursion is set to meet with the FDA this year to align on a regulatory path for REC-4881.
Recursion’s AI-heavy approach has attracted several of the industry’s biggest players, including Sanofi, Roche and Bayer, but the techbio player has also had its fair share of challenges. In August 2024, Recursion merged with Exscientia—and proceeded to shed employees shortly after. In November 2024, Recursion announced layoffs that a spokesperson at the time said would affect less than 20% of the workforce.
The company followed this up with another round of cuts in June 2025, trimming another 20% of its headcount in line with “post-integration employee transitions” and in a bid to streamline its strategy. This move, Recursion said at the time, would keep it going into the fourth quarter of 2027.
