false 0001609809 0001609809 2022-03-01 2022-03-01












Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 1, 2022




(Exact name of Registrant as Specified in Its Charter)




Delaware   001-37465   27-4326290

(State or other jurisdiction

of incorporation)



File Number)


(IRS Employer

Identification No.)


200 Sidney Street - 4th Floor

Cambridge, MA

(Address of principal executive offices)   (Zip Code)

Registrant’s telephone number, including area code: (617) 945-9626

Not Applicable

(Former Name or Former Address, if Changed Since Last Report)



Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:


Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)


Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)


Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))


Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:


Title of each class





Name of each exchange

on which registered

Common stock, par value $0.001 per share   MCRB   The Nasdaq Stock Market LLC
    (Nasdaq Global Select Market)

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐




Item 2.02.

Results of Operations and Financial Condition.

On March 1, 2022, Seres Therapeutics, Inc. (the “Company”) announced its financial results for the quarter and year ended December 31, 2021 and provided operational updates. The full text of the press release issued in connection with the announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K (the “Current Report”).

The information in this Item 2.02 of this Current Report (including Exhibit 99.1) shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.


Item 9.01.

Financial Statements and Exhibits.

(d) Exhibits

The following Exhibit 99.1 relates to Item 2.02 and shall be deemed to be furnished, and not filed:


99.1    Seres Therapeutics, Inc. Press Release issued March 1, 2022
104    Cover Page Interactive Data File (embedded within the Inline XBRL document)


Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.


Date: March 1, 2022   By:  

/s/ Thomas J. DesRosier

  Name:   Thomas J. DesRosier
  Title:   Chief Legal Officer and Executive Vice President

Exhibit 99.1



Seres Therapeutics Reports Fourth Quarter and Full Year 2021 Financial Results and Provides Business Updates

SER-109 Phase 3 study results in recurrent C. difficile infection published in New England Journal of Medicine

– Biologics License Application (BLA) filing for SER-109 anticipated in mid-2022

– Investor webcast highlighted the broad potential of microbiome therapeutics as a novel approach for Infection Protection in medically compromised individuals –

– Conference call at 8:30 a.m. ET today –

CAMBRIDGE, Mass., March 1, 2022 Seres Therapeutics, Inc. (Nasdaq: MCRB), a leading microbiome therapeutics company, today reported fourth quarter and full year 2021 financial results and provided business updates.

“The progress made throughout 2021 has set the stage for an exciting year ahead for Seres, highlighted by the anticipated BLA filing for SER-109 with the U.S. Food and Drug Administration (FDA) for recurrent C. difficile infection (rCDI) in mid-2022 which, if approved, we expect to be the first ever microbiome therapeutic” said Eric Shaff, Chief Executive Officer at Seres. “In collaboration with Nestlé Health Science, we are executing on our plans for a successful SER-109 product launch. Together, we are committed to bringing this potentially transformative therapeutic option to patients suffering with rCDI.”

“As highlighted during our recent investor event, we are also advancing our earlier stage efforts in Infection Protection, including the recently initiated SER-155 Phase 1b study to evaluate safety and efficacy in individuals undergoing allogeneic hematopoietic stem cell transplantation. We believe that our microbiome approach has the potential to result in transformative new medicines for Infection Protection, a therapeutic category in great need of innovation,” continued Mr. Shaff.

Program and Corporate Updates

SER-109 Phase 3 ECOSPOR III study in recurrent C. difficile infection: SER-109, an investigational oral, live microbiome therapeutic, achieved its primary endpoint of superiority to placebo in reducing CDI recurrence in a Phase 3 clinical trial in patients with rCDI. The Company continues to prepare for a BLA filing with the FDA.

Seres has achieved target enrollment in its open-label study of SER-109 in patients with rCDI (ClinicalTrials.gov identifier: NCT03183141), which also admits patients with a single recurrence of rCDI, to expand the SER-109 safety database. Based on FDA commentary, Seres believes the ECOSPOR III efficacy results should support a BLA filing as a single pivotal study. Seres intends to finalize a BLA submission, including data from the open-label study, in mid-2022.

While executing multiple activities necessary to support the BLA submission, Seres is also preparing for a successful product launch with Aimmune, the division within Nestlé Health Science leading commercialization efforts. The Company believes that a substantial commercial opportunity exists for SER-109. The cost of a patient with recurrence of CDI has been estimated to result in approximately $34,000 in annual direct healthcare expenses; this does not include the substantial indirect costs associated with this disease. There are approximately 170,000 cases of rCDI annually in the U.S. and CDI results in over 20,000 deaths.

In January 2022, the New England Journal of Medicine (NEJM) published data from the SER-109 Phase 3 ECOSPOR III study evaluating SER-109 for the treatment of rCDI. The publication highlights key results including that SER-109 was superior to placebo in reducing CDI recurrence, with 88% of SER-109 patients achieving a sustained clinical response compared to 60% on placebo. SER-109 was well tolerated, with a side effect profile comparable to placebo and no serious drug-related adverse events observed.

In November 2021, the Company initiated a SER-109 expanded access program at various sites across the U.S. The program is designed to enable eligible adults with rCDI to obtain access to SER-109 prior to a potential FDA product approval.

In October 2021, Seres announced the presentation of an exploratory analysis of its SER-109 Phase 3 ECOSPOR III study at the American College of Gastroenterology 2021 Annual Meeting. Data demonstrate that SER-109 reduced the risk of rCDI, as compared to subjects administered placebo, in individuals with risk factors for recurrence, including those taking acid-reducing medications such as proton pump inhibitors and H2 blockers.

In November 2021, Seres announced a collaboration with Bacthera, a specialized contract development and manufacturing organization to manufacture SER-109, Seres’ lead product candidate for rCDI. The collaboration is designed to expand upon existing production capacity to meet demand growth beyond the initial phase of an anticipated product launch.

SER-155 Phase 1b clinical study activities: In December 2021, Seres announced the enrollment of the first patient in the Company’s Phase 1b clinical study of SER-155 designed to evaluate safety, microbiome alterations, and the impact on infections and/or graft versus host disease (GvHD) associated with SER-155 in adult subjects who are undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). The study is currently being conducted with Memorial Sloan Kettering Cancer Center and the University of Chicago.

SER-155 is an investigational oral, rationally designed, cultivated microbiome therapeutic designed to reduce the incidence of gastrointestinal infections, bloodstream infections, and graft versus host disease (GvHD) in patients receiving allo-HSCT. SER-155 is a consortium of bacterial species selected using Seres’ reverse translation discovery and development platforms. The design incorporates microbiome biomarker data from human clinical data and nonclinical human cell-based assays and in vivo disease models. The SER-155 composition aims to decrease infection and translocation of antibiotic-resistant bacteria in the gastrointestinal tract and modulate host immune responses to decrease GvHD. In addition to SER-109, SER-155 represents Seres’ second active development program in its Infection Protection franchise.

Infection Protection Investor Event: In January 2022, Seres held a webcast event that highlighted development of microbiome therapeutics as a novel approach for Infection Protection in medically compromised individuals. Building upon SER-109, and in addition to SER-155, Seres is also evaluating additional preclinical stage programs in indications such as cancer neutropenia, solid organ transplant, and antimicrobial resistant infections more broadly.

Ulcerative colitis (UC) development efforts: In July 2021, Seres announced topline results from the Phase 2b ECO-RESET study evaluating SER-287, a donor-derived investigational microbiome therapeutic candidate, in patients with mild-to-moderate UC. The study did not meet its primary endpoint of improving clinical remission rates compared to placebo. Both dosing regimens of SER-287 were generally well tolerated. In December 2021, Seres announced preliminary microbiome drug pharmacology analyses from the study. Engraftment of SER-287 bacteria was statistically significant in patients receiving SER-287 versus placebo (p ≤ 0.001 at all timepoints), however, unlike the Phase 1b study, anticipated changes in disease-relevant metabolites post-administration with SER-287 in the Phase 2b study were not observed. As previously reported, SER-287 Phase 2b clinical and microbiome data suggest that there may be an opportunity to utilize biomarker-based patient selection in future UC development efforts.

Seres has completed preliminary data analysis data from the first cohort of the SER-301 Phase 1b study in subjects with mild-to-moderate UC, which included 15 subjects. Evaluation of the first cohort data by an independent Data Safety Monitoring Board indicated that it would be safe to proceed to the placebo-controlled second cohort. While clinical efficacy was not a defined endpoint in the first cohort, evaluation of outcome data indicated that no subjects achieved clinical remission as defined by the FDA using the Three-Component Modified Mayo Score after 10 weeks of treatment, though there were improvements in one or more individual components, (endoscopic, stool frequency and rectal bleeding sub scores) in some patients.

SER-301 led to modulation of the metabolic landscape in the gastrointestinal tract, including in short-chain and medium-chain fatty acids, tryptophan-derived metabolites, bile acids, and other microbe-associated metabolites, as well as host metabolites associated with a non-disease state. SER-301 strains were observed to engraft in subjects across the trial period. The degree of metabolic changes observed following SER-301 administration appeared to be dependent on the baseline metabolic profile of the study subjects, providing support for the potential for microbiome therapeutics to be developed in biomarker-identified UC patient subpopulations.

The SER-287 and SER-301 clinical and drug pharmacology data sets obtained to date provide a robust set of insights into the role of the microbiome in UC, and Seres continues to conduct analyses of data from our SER-287 and SER-301 programs to inform next steps for further development.

Appointment of Executive Vice President, Chief People Officer: In February 2022, Seres announced that Paula Cloghessy joined Seres, bringing more than 20 years of human resources expertise with broad business experience. She most recently served as Chief People Officer at Translate Bio, Inc., where she led the talent architecture and people strategy. She previously served as vice president of human resources at Joule Unlimited Technologies, Inc. She has also held human resources positions at Interleukin Genetics, Inc. and NUCRYST Pharmaceuticals, Inc.

Financial Results

Seres reported a net loss of $65.6 million for the full year of 2021, as compared to a net loss of $89.1 million for the prior year. Seres reported a net loss of $50.0 million for the fourth quarter of 2021, as compared to a net loss of $18.3 million for the same period in 2020.

Research and development expenses for the fourth quarter of 2021 were $36.8 million, as compared to $24.9 million for the same period in 2020. The research and development expenses were primarily related to Seres’ late-stage SER-109 clinical development program and manufacturing costs, as well as personnel expenses.

General and administrative expenses for the fourth quarter were $20.5 million, as compared to $10.6 million for the same period in the prior year. General and administrative expenses were primarily related to personnel expenses, professional fees, including SER-109 commercial readiness and pre-launch expenses, and facility costs.

Seres amended its debt financing agreement with Hercules Capital in February 2022, providing the Company with an additional $50 million in capital, for up to $100 million in total. Upon closing, Hercules advanced $50 million to the Company under the facility, of which $22.1 million was previously outstanding, resulting in proceeds of $27.6 million, net of fees and expenses. The Company will make interest only payments through December 31, 2023, extendable to December 31, 2024 with SER-109 approval. There are two subsequent tranches of $25 million each, one of which becomes available to the Company upon the FDA’s approval of the BLA for SER-109 by December 15, 2023 and the second of which becomes available upon the satisfaction of certain conditions, including Hercules’ investment committee approval.

Seres ended the 2021 year with approximately $291.2 million in cash, cash equivalents and short and long-term investments as compared with approximately $353.2 million at the end of the third quarter 2021.

Conference Call Information

Seres’ management will host a conference call today, March 1, 2022, at 8:30 a.m. ET. To access the conference call, please dial 844-277-9450 (domestic) or 336-525-7139 (international) and reference the conference ID number 6277858. To join the live webcast, please visit the “Investors and News” section of the Seres website at www.serestherapeutics.com.

A webcast replay will be available on the Seres website beginning approximately two hours after the event and will be archived for at least 21 days.

About Seres Therapeutics

Seres Therapeutics, Inc. (Nasdaq: MCRB) is a leading microbiome therapeutics company developing a novel class of multifunctional bacterial consortia that are designed to functionally interact with host cells and tissues to treat disease. Seres’ SER-109 program achieved the first-ever positive pivotal clinical results for a targeted microbiome drug candidate and has obtained Breakthrough Therapy and Orphan Drug designations from the FDA. The SER-109 program is being advanced to reduce the recurrence of C. difficile infection and has potential to become a first-in-class FDA-approved microbiome therapeutic. Seres is evaluating SER-301 in a Phase 1b study in patients with ulcerative colitis and SER-155 in a Phase 1b study in patients receiving allogeneic hematopoietic stem cell transplantation to reduce incidences of gastrointestinal infections, bloodstream infections and graft-versus-host disease as well as additional preclinical stage programs targeting Infection Protection in medically compromised patients.

For more information, please visit www.serestherapeutics.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including the potential approval of SER-109 and its status as a first-in-class therapeutic, the timing of a BLA filing, the market for SER-109, and our capacity for commercial supply of SER-109; the anticipated indication and potential impact of infection protection microbiome therapeutics; the ability to utilize biomarker-based patient selection in UC development; plans, timing and potential impact of the release of additional preclinical and clinical data; our development opportunities, including the future of development in UC; the ultimate safety and efficacy data for our products; the potential of microbiome therapeutics to treat and prevent disease; the safety, efficacy and regulatory and clinical progress of our product candidates; the potential benefits of our collaborations; and other statements which are not historical fact.

These forward-looking statements are based on management’s current expectations. These statements are neither promises nor guarantees, but involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including, but not limited to, the following: we have incurred significant losses, are not currently profitable and may never become profitable; our need for additional funding; our limited operating history; the impact of the

COVID-19 pandemic; our unproven approach to therapeutic intervention; the lengthy, expensive and uncertain process of clinical drug development; our reliance on third parties and collaborators to conduct our clinical trials, manufacture our product candidates and develop and commercialize our product candidates, if approved; and our ability to retain key personnel and to manage our growth. These and other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission, or SEC, on November 10, 2021, and our other reports filed with the SEC could cause actual results to differ materially from those indicated by the forward-looking statements made in this press release. Any such forward-looking statements represent management’s estimates as of the date of this press release. While we may elect to update such forward-looking statements at some point in the future, we disclaim any obligation to do so, even if subsequent events cause our views to change. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.



(In thousands, except share and per share data)


     December 31,  
     2021     2020  



Current assets:


Cash and cash equivalents

   $ 180,002     $ 116,049  

Short term investments

     110,704       137,567  

Prepaid expenses and other current assets

     12,922       5,774  

Accounts receivable

     —         9,387  







Total current assets

     303,628       268,777  

Property and equipment, net

     17,938       13,897  

Operating lease assets

     18,208       9,041  

Restricted cash

     8,000       —    

Restricted investments

     1,401       1,400  

Long term investments

     495       49,825  

Other non-current assets

     5,189       —    







Total assets

   $ 354,859     $ 342,940  







Liabilities and Stockholder’s Equity


Current liabilities:


Accounts payable

   $ 13,735     $ 4,018  

Accrued expenses and other current liabilities (1)

     45,094       14,226  

Operating lease liabilities

     6,610       5,115  

Short term portion of note payable, net of discount

     —         454  

Deferred revenue - related party

     16,819       22,602  







Total current liabilities

     82,258       46,415  

Long term portion of note payable, net of discount

     24,643       24,639  

Operating lease liabilities, net of current portion

     17,958       10,561  

Deferred revenue, net of current portion - related party

     86,998       85,572  

Other long-term liabilities (2)

     11,495       1,003  







Total liabilities

     223,352       168,190  







Commitments and contingencies


Stockholders’ equity:


Preferred stock, $0.001 par value; 10,000,000 shares authorized at December 31, 2021 and 2020; no shares issued and outstanding at December 31, 2021 and 2020

     —         —    

Common stock, $0.001 par value; 200,000,000 shares authorized at December 31, 2021 and 2020; 91,889,418 and 91,459,239 shares issued and outstanding at December 31, 2021 and 2020

     92       91  

Additional paid-in capital

     745,829       723,482  

Accumulated other comprehensive loss

     (60     (47

Accumulated deficit

     (614,354     (548,776







Total stockholders’ equity

     131,507       174,750  







Total liabilities and stockholders’ equity

   $ 354,859     $ 342,940  









Includes related party amounts of $21,098 and $0 at December 31, 2021 and December 31, 2020, respectively


Includes related party amounts of $10,585 and $0 at December 31, 2021 and December 31, 2020, respectively



(In thousands, except share and per share data)


     Year Ended December 31,  
     2021     2020     2019  



Collaboration revenue - related party

   $ 143,857     $ 11,897     $ 27,188  

Grant revenue

     1,070       4,157       1,102  

Collaboration revenue

     —         17,161       6,215  










Total revenue

     144,927       33,215       34,505  

Operating expenses:


Research and development expenses

   $ 141,891     $ 90,570     $ 80,141  

General and administrative expenses

     69,261       30,775       24,748  

Collaboration (profit) loss sharing—related party

     (1,732     —         —    

Restructuring expenses

     —         —         1,492  










Total operating expenses

     209,420       121,345       106,381  










Loss from operations

     (64,493     (88,130     (71,876










Other (expense) income:


Interest income

     2,870       946       1,033  

Interest expense

     (2,910     (2,924     (502

Other (expense) income

     (1,045     981       1,066  










Total other (expense) income, net

     (1,085     (997     1,597  










Net loss

   $ (65,578   $ (89,127   $ (70,279

Net loss per share attributable to common stockholders, basic and diluted

   $ (0.72   $ (1.12   $ (1.24










Weighted average common shares outstanding, basic and diluted

     91,702,866       79,789,220       56,649,220  










Other comprehensive loss:


Unrealized loss on investments, net of tax of $0

     (12     (47     —    

Currency translation adjustment

     (1     —         —    










Total other comprehensive loss

     (13     (47     —    










Comprehensive loss

   $ (65,591   $ (89,174   $ (70,279










PR Contact

Kristin Ainsworth


IR Contact

Carlo Tanzi, Ph.D.