Assembly Biosciences (Nasdaq: ASMB) priced a registered underwritten offering of approximately $100 million in common stock and pre-funded warrants. The deal covers 3,358,602 shares at $26.50 each and 415,000 pre-funded warrants at $26.499, plus a 30-day option for 566,040 additional shares.
All securities are offered by the company, with closing expected around May 26, 2026. Proceeds are planned to fund clinical development of pipeline candidates and general corporate purposes. Participants include new and existing healthcare-focused investors such as Gilead Sciences and several specialist funds.
Loading…
Loading translation…
AI-generated analysis. Not financial advice.
Positive
- Gross offering proceeds expected at approximately $100 million
- Participation from healthcare-focused investors including Gilead Sciences and specialist funds
- 30-day underwriter option for up to 566,040 additional shares
- Net proceeds earmarked to fund clinical development pipeline and corporate needs
Negative
- Issuance of 3,358,602 new shares increases share count and may dilute existing holders
- Pre-funded warrants for up to 415,000 shares add potential future dilution
- Additional 566,040-share underwriter option could further increase dilution if exercised
Gross proceeds
$100,000,000
Expected gross proceeds from underwritten offering before fees
Common shares offered
3,358,602 shares
Shares of common stock in the underwritten offering
Pre-funded warrants
415,000 warrants
Pre-funded warrants to purchase common shares
Common share offer price
$26.50 per share
Offering price per share of common stock
Pre-funded warrant price
$26.499 per warrant
Offering price per pre-funded warrant
Warrant exercise price
$0.001 per share
Exercise price per share underlying each pre-funded warrant
Underwriters’ option
566,040 shares
30-day option for additional common shares
$28.20
Last Close
Volume
Volume 48,989 vs 20-day average 130,262 (relative volume 0.38) ahead of the offering news.
low
Technical
Shares at $26.485, trading below 200-day MA of $28.88 and about 33.3% under the 52-week high.
ASMB is up 0.91% while scanner peers show mixed moves: IMRX up 7.47% and RCKT down 2.88%, suggesting a stock-specific reaction rather than a coordinated biotech move.
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| May 13 |
HDV Phase 1a data |
Positive |
+2.9% |
Announcement of upcoming topline Phase 1a ABI-6250 data at EASL 2026. |
| May 11 |
Conference presentation |
Neutral |
+2.3% |
Notification of BofA healthcare conference presentation and webcast access. |
| May 07 |
Q1 2026 earnings |
Positive |
-3.9% |
Q1 2026 results with solid cash runway and pipeline milestones but shares fell. |
| Apr 09 |
HSV Phase 1b data |
Positive |
+1.7% |
Positive Phase 1b data for ABI-5366 and ABI-1179 in recurrent genital herpes. |
| Mar 19 |
FY 2025 earnings |
Positive |
+3.5% |
Year-end 2025 results with strong cash, Gilead fees and pipeline progress. |
Recent ASMB headlines, especially pipeline and collaboration updates, have most often coincided with modest positive price reactions, with one earnings report showing a negative divergence.
Over the past six months, ASMB has reported earnings and multiple pipeline updates, often tied to its collaborations and clinical progress. Year-end 2025 and Q1 2026 results highlighted strong cash levels, Gilead collaboration revenue, and advancement of HSV and HDV candidates, with mixed price reactions around earnings. Scientific meeting presentations on ABI‑5366, ABI‑1179 and ABI‑6250 have generally seen mildly positive moves. Today’s equity offering follows this period of active clinical and financial disclosure, adding new capital on top of previously reported cash balances.
$400,000,000
registered capacity
An effective S-3 shelf filed on 2026-03-19 registers up to $400,000,000 of securities, including a $100,000,000 at-the-market common stock program with Jefferies LLC as sales agent. Today’s underwritten offering utilizes this registered capacity and represents additional potential dilution on top of the existing ATM authorization.
This announcement prices a sizeable underwritten equity and pre-funded warrant offering, targeting gross proceeds of about $100,000,000 via 3,358,602 new shares and 415,000 pre-funded warrants at roughly the current trading level. It draws on an effective S-3 shelf for up to $400,000,000, which also includes a $100,000,000 ATM. Investors may track how efficiently these funds support clinical development, while considering cumulative dilution from both this deal and any future shelf or ATM usage.
pre-funded warrants
financial
“pre-funded warrants to purchase up to 415,000 shares of common stock at an offering price…”
Pre-funded warrants are financial instruments that give investors the right to purchase a company’s stock at a set price, but with most or all of the purchase price paid upfront. They function like a coupon or gift card for stock, allowing investors to buy shares later at a fixed price, which can be beneficial if they want to avoid future price increases. This makes them important for investors seeking flexibility and certainty in their investment plans.
underwritten, registered offering
financial
“today announced the pricing of an underwritten, registered offering (the offering)…”
An underwritten, registered offering is a sale of securities that has been formally filed with regulators (registered) and arranged by one or more investment banks that commit to buy and resell the securities (underwritten). Think of it as a store getting a municipal permit to sell a new product and a wholesaler agreeing to buy the first shipment: it shows regulatory clearance and a guaranteed market for the issue, but can dilute existing holders and affects share supply, price and costs to the issuer.
shelf registration statement
regulatory
“A shelf registration statement relating to the securities being sold in the offering has been filed…”
A shelf registration statement is a document a company files with regulators that allows it to sell shares or bonds quickly when it’s a good time to raise money. It’s like having a pre-approved plan ready so the company can act fast without going through lengthy paperwork each time they want to sell, making fundraising more flexible.
prospectus supplement
regulatory
“A preliminary prospectus supplement and a final prospectus supplement relating to the offering will be filed…”
A prospectus supplement is an additional document provided alongside a company’s main offering details, offering updated or extra information about a specific financial product being sold. It helps investors understand the latest terms, risks, and details of the investment, similar to how an update or revision clarifies or expands on original instructions, ensuring they have current and complete information before making a decision.
Securities and Exchange Commission (SEC)
regulatory
“has been filed with the Securities and Exchange Commission (SEC) and was declared effective…”
A U.S. federal agency that oversees the stock and securities markets, requiring public companies and brokers to register and share accurate financial information so investors can see the facts. It enforces rules, investigates fraud and can pause or change market activity; think of it as a referee whose decisions and investigations affect investor confidence, legal risk and the value of traded securities.
AI-generated analysis. Not financial advice.
SOUTH SAN FRANCISCO, Calif., May 22, 2026 (GLOBE NEWSWIRE) — Assembly Biosciences, Inc. (Nasdaq: ASMB), a biotechnology company developing innovative therapeutics targeting serious viral and liver diseases, today announced the pricing of an underwritten, registered offering (the offering) of an aggregate of 3,358,602 shares of common stock at an offering price per share of common stock of
The offering includes participation from new and existing investors, including Gilead Sciences, Inc., Commodore Capital, Farallon Capital Management, Seven Fleet Capital, Sirenia Capital Management LP, Columbia Threadneedle Investments, Paradigm BioCapital Advisors, Squadron Capital Management, a large global mutual fund, and other healthcare-dedicated investors.
All shares of common stock and pre-funded warrants to be sold in the offering will be offered by Assembly Bio. The offering is expected to close on or about May 26, 2026, subject to the satisfaction of customary closing conditions.
Assembly Bio plans to use the net proceeds from the offering to fund clinical development of pipeline candidates and for general corporate purposes.
Guggenheim Securities and UBS Investment Bank are acting as joint book-running managers for the offering. Mizuho is also acting as a book-running manager for the offering. H.C. Wainwright & Co. is acting as lead manager for the offering.
A shelf registration statement relating to the securities being sold in the offering has been filed with the Securities and Exchange Commission (SEC) and was declared effective on March 27, 2026. A preliminary prospectus supplement and a final prospectus supplement relating to the offering will be filed with the SEC and will be available on the SEC’s website at www.sec.gov. When available, copies of the preliminary prospectus supplement and final prospectus supplement may be obtained by contacting Guggenheim Securities, LLC, Attention: Equity Syndicate Department, 330 Madison Avenue, 8th Floor, New York, New York 10017, by telephone at (212) 518-9544, or by email at GSEquityProspectusDelivery@guggenheimpartners.com; or UBS Securities LLC, Attention: Prospectus Department, UBS Investment Bank, 11 Madison Avenue, New York, New York 10010 or by email at ol-prospectus-request@ubs.com.
This press release shall not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.
About Assembly Biosciences
Assembly Biosciences is a biotechnology company dedicated to the development of innovative small-molecule therapeutics designed to change the path of serious viral and liver diseases and improve the lives of patients worldwide. Led by an accomplished team of leaders in viral and liver diseases, Assembly Bio is committed to improving outcomes for patients struggling with the serious, chronic impacts of herpesvirus, hepatitis delta virus (HDV) infections, cholestatic liver diseases and hepatitis B virus (HBV).
Forward-Looking Statements
The information in this press release contains forward-looking statements that are subject to certain risks and uncertainties that could cause actual results to materially differ. These forward-looking statements include statements about the offering, including the expected timing and completion thereof and use of proceeds therefrom. These risks and uncertainties include: Assembly Bio’s ability to realize the potential benefits of its collaboration with Gilead Sciences, Inc. (Gilead), including all financial aspects of the collaboration and equity investments; Assembly Bio’s ability to initiate and complete clinical studies involving its therapeutic product candidates, including studies contemplated by Assembly Bio’s collaboration with Gilead, in the currently anticipated timeframes or at all; safety and efficacy data from clinical or nonclinical studies may not warrant further development of Assembly Bio’s product candidates; clinical and nonclinical data may not differentiate Assembly Bio’s product candidates from other companies’ candidates; Assembly Bio’s ability to maintain financial resources necessary to continue its research activities, clinical studies and other business operations; potential effects of changes in government regulation; results of nonclinical studies may not be representative of disease behavior in a clinical setting and may not be predictive of the outcomes of clinical studies; and other risks identified from time to time in Assembly Bio’s reports filed with the U.S. Securities and Exchange Commission (the SEC). You are urged to consider statements that include the words may, will, would, could, should, might, believes, hopes, estimates, projects, potential, expects, plans, anticipates, intends, continues, forecast, designed, goal or the negative of those words or other comparable words to be uncertain and forward-looking. Assembly Bio intends such forward-looking statements to be covered by the safe harbor provisions contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. More information about Assembly Bio’s risks and uncertainties are more fully detailed under the heading “Risk Factors” in Assembly Bio’s filings with the SEC, including its most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. Except as required by law, Assembly Bio assumes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events or otherwise.
Contacts:
Investors:
Patrick Till
Meru Advisors
(484) 788-8560
investor_relations@assemblybio.com
Media:
Jamie Strachota
Sam Brown Healthcare Communications, Inc.
(703) 819-7647
ASMBMedia@sambrown.com
FAQ
What did Assembly Biosciences (ASMB) announce on May 22, 2026?
Assembly Biosciences announced pricing of a roughly $100 million underwritten offering of common stock and pre-funded warrants. According to Assembly Bio, all securities are being sold by the company to support clinical development and general corporate purposes.
What are the key terms of Assembly Biosciences’ $100 million stock offering (ASMB)?
The offering includes 3,358,602 common shares at $26.50 and 415,000 pre-funded warrants at $26.499. According to Assembly Bio, underwriters also have a 30-day option to buy up to 566,040 additional shares at the public offering price, excluding discounts.
How will Assembly Biosciences (ASMB) use the proceeds from its May 2026 offering?
Assembly Biosciences plans to use net proceeds to fund clinical development of pipeline candidates and for general corporate purposes. According to Assembly Bio, the capital raise supports advancement of its therapeutics targeting serious viral and liver diseases.
When is Assembly Biosciences’ (ASMB) new stock and warrant offering expected to close?
The offering is expected to close on or about May 26, 2026, subject to customary conditions. According to Assembly Bio, Guggenheim Securities, UBS Investment Bank, Mizuho, and H.C. Wainwright & Co. are managing the transaction as book-runners or lead manager.
Who is participating in Assembly Biosciences’ May 2026 stock offering (ASMB)?
The offering includes participation from new and existing investors such as Gilead Sciences, Commodore Capital, Farallon Capital Management, and other healthcare-focused funds. According to Assembly Bio, the investor group also features a large global mutual fund.