false 0001829802 0001829802 2022-08-09 2022-08-09





Washington, D.C. 20549







Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 9, 2022



Sensei Biotherapeutics, Inc.

(Exact Name of Registrant as Specified in its Charter)




Delaware   001-39980   83-1863385

(State or Other Jurisdiction

of Incorporation)



File Number)


(IRS Employer

Identification No.)


451 D Street, Suite 710

Boston, MA

(Address of Principal Executive Offices)   (Zip Code)

Registrant’s telephone number, including area code: (240) 243-8000



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 Securities Exchange Act of 1934:


Title of each class





Name of each exchange

on which registered

Common Stock   SNSE   The Nasdaq Stock Market LLC

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 August 9, 2022, Sensei Biotherapeutics, Inc. (the “Company”) issued a press release announcing its financial results for the quarter ended June 30, 2022. A copy of the press release is attached hereto as Exhibit 99.1.


Item 7.01

Regulation FD Disclosure.

On August 9, 2022, the Company updated its corporate presentation for use in meetings with investors, analysts and others. A copy of the presentation is furnished as Exhibit 99.2 to this Current Report on Form 8-K.

The information in Item 2.02 and Item 7.01 and the exhibits attached hereto are being furnished and shall not be deemed “filed” for the 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 they be deemed incorporated by reference into any filing under the Exchange Act or the Securities Act of 1933, as amended, whether filed before or after the date hereof and regardless of any general incorporation language in such filing.


Item 9.01

Financial Statements and Exhibits.

(d) Exhibits




Exhibit Description

99.1    Press Release of Sensei Biotherapeutics, Inc., dated August 9, 2022
99.2    Sensei Biotherapeutics, Inc. corporate presentation, dated August 2022
104    The cover page from this Current Report on Form 8-K, formatted in Inline XBRL





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.


      Sensei Biotherapeutics, Inc.
Date: August 9, 2022      

/s/ John Celebi

      John Celebi
      President and Chief Executive Officer




Exhibit 99.1

Sensei Biotherapeutics Reports Second Quarter 2022 Financial Results and Recent Business Highlights

- SNS-101 pre-IND feedback received from FDA with program on track for IND filing in first half of 2023 -

- New SNS-101 single dose pharmacokinetic data in non-human primates to be presented in the third quarter of 2022 -

- On track with SNS-102 candidate selection, including generation of pH-sensitive parental antibodies -

- Strong balance sheet with cash runway into the first quarter of 2025 -

BOSTON, MA – August 9, 2022 – Sensei Biotherapeutics, Inc. (NASDAQ: SNSE), an immuno-oncology company focused on the discovery and development of next generation therapeutics for cancer, today reported financial results for the second quarter ended June 30, 2022 and provided recent business updates.

“This has been a productive and rewarding time as we progress our TMAb platform in pursuit of potentially revolutionary therapies for cancer patients that address the challenge of resistance to checkpoint blockade. Our TMAb platform is designed to generate conditionally active antibodies with enhanced tumor specificity. Notably, we have been pleased with the breakthrough preclinical data on SNS-101, our anti-VISTA antibody, which we believe support our hypothesis that an antibody binding selectively in low-pH environments has the potential to effectively inhibit tumor growth across a range of indications without on-target, off-tumor effects,” said John Celebi, president and chief executive officer of Sensei Biotherapeutics. “We have also achieved a milestone with the generation of pH-sensitive antibodies for a second program targeting VSIG4. With cash runway into 2025, we believe we are well positioned to achieve near-term milestones, including the anticipated submission of an Investigational New Drug application for SNS-101 in the first half of 2023.”

Highlights and Milestones


Sensei continues preclinical studies to evaluate SNS-101, a monoclonal antibody targeting the immune checkpoint VISTA (V-domain Ig suppressor of T cell activation), which is implicated in resistance to PD-1/PD-L1 therapy and correlates with poor survival across numerous cancers. Recent updates for SNS-101 include:



Sensei has received pre-IND meeting feedback from the U.S. Food and Drug Administration and expects to submit an IND in the first half of 2023.



The Company plans to present new data from a single dose pharmacokinetic (PK) and toxicology model in non-human primates in the third quarter of 2022.



Sensei will present new preclinical cytokine release data comparing SNS-101 to a non-pH-selective anti-VISTA antibody at the Sixth CRI-ENCI-AACR International Cancer Immunotherapy Conference: Translating Science Into Survival, being held September 28 - October 1, 2022 in New York City.


In April 2022, Sensei presented preclinical data demonstrating that SNS-101 had a favorable pharmacokinetic profile in a single-dose mouse model. Notably, SNS-101 demonstrated a long mean residence time in the blood, indicating a lack of significant target-mediated drug disposition and clearance in non-malignant tissues.



Also in April 2022, preclinical data in an MC38 syngeneic tumor model in human VISTA knock-in mice demonstrated synergistic anti-tumor activity in combination with anti-PD-1 therapy.



SNS-101 has demonstrated excellent manufacturing productivity to date and GMP manufacturing timelines remain on track.


Sensei is advancing several pH-sensitive antibodies targeting VSIG4 (V-Set and Immunoglobulin Domain Containing 4). VSIG4 is a B7-family related protein that is a potent inhibitor of T cell activity and is frequently overexpressed on tumor-associated macrophages.



Sensei remains on track to select a product candidate and initiate IND-enabling studies in 2023.



Sensei has identified eight parental pH-sensitive antibodies targeting VSIG4 for further optimization.



The Company aims to develop a pH-dependent, high-affinity inhibitory antibody which selectively binds VSIG4 in the tumor microenvironment versus normal tissue.




Sensei remains on track to select a product candidate in 2023 for SNS-103, a monoclonal antibody targeting ENTPDase1 (ecto-nucleoside triphosphate diphosphohydrolase-1, also known as CD39), the upstream, rate-limiting enzyme that leads to the breakdown of extracellular ATP.

Second Quarter 2022 Financial Results

Cash Position: Cash, cash equivalents and marketable securities were $123.7 million as of June 30, 2022, as compared to $147.6 million as of December 31, 2021. Sensei expects its current cash balance to fund operations into the first quarter of 2025.

Research and Development (R&D) Expenses: R&D expenses were $6.4 million for the quarter ended June 30, 2022, compared to $5.9 million for the quarter ended June 30, 2021. The increase in R&D expenses was primarily attributable to increased headcount and inflation on supplies to support Sensei’s research, development, and manufacturing activities.

General and Administrative (G&A) Expenses: G&A expenses were $4.3 million for the quarter ended June 30, 2022, compared to $3.9 million for the quarter ended June 30, 2021, with the increase mainly driven by franchise tax increases.

Net Loss: Net loss was $10.5 million for the quarter ended June 30, 2022, compared to $9.8 million for the quarter ended June 30, 2021.

Condensed Statements of Operations

(Unaudited, in thousands except share and per share data)


     Three Months Ended June 30,  
     2022      2021  

Operating expenses:


Research and development

   $ 6,393      $ 5,898  

General and administrative

     4,319        3,886  







Total operating expenses

     10,712        9,784  







Loss from operations

     (10,712      (9,784

Total other income (expense)

     177        13  

Net loss

     (10,535      (9,771

Net loss per share, basic and diluted

   $ (0.34    $ (0.32







Weighted-average common shares outstanding, basic and diluted

     30,701,758        30,588,495  







Selected Condensed Balance Sheet Data

(Unaudited, in thousands)


     June 30,
     December 31,

Cash and cash equivalents

   $ 9,899      $ 7,159  

Marketable Securities

     113,815        140,462  

Total assets

     138,036        153,225  

Total liabilities

     12,120        6,712  

Total stockholders’ equity (deficit)

     125,916        146,513  

About Sensei Biotherapeutics

Sensei Biotherapeutics (NASDAQ: SNSE) is an immuno-oncology company focused on the discovery and development of next generation therapeutics for cancer. Sensei has designed two unique approaches to develop highly selective therapeutics – its TMAb (Tumor Microenvironment Activated biologics) platform, which disables checkpoints and other immunosuppressive signals in the tumor microenvironment to unleash existing T cells against tumors, and the ImmunoPhage platform, which trains new T cells to recognize and kill malignant cells. Using its TMAb platform, the company is developing SNS-101, a fully human antibody designed to block the V-domain Ig suppressor of T cell activation (VISTA) checkpoint selectively only within the low pH tumor microenvironment, where VISTA acts as a suppressor of T cells by binding the receptor PSGL-1. The company is also using its platforms to develop other preclinical programs targeting multiple solid tumor indications. For more information, please visit, and follow the company on Twitter @SenseiBio and LinkedIn.

Cautionary Note Regarding Forward-Looking Statements

Any statements contained in this press release that do not describe historical facts may constitute forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements may be identified by words and phrases such as “believe”, “designed to,” “expect”, “may”, “plan”, “potential”, “will”, and similar expressions, and are based on Sensei’s current beliefs and expectations. These forward-looking statements include expectations regarding the development and potential therapeutic benefits of Sensei’s product candidates and platforms, the expected safety profile of Sensei’s product candidates, the availability of data from Sensei’s preclinical studies, the timing of selection of product candidates, the timing of IND submissions to the FDA, and its belief that its existing cash and cash equivalents will be sufficient to fund its operations at least into the first quarter of 2025. These statements involve risks and uncertainties that could cause actual results to differ materially from those reflected in such statements. Risks and uncertainties that may cause actual results to differ materially include uncertainties inherent in the development of therapeutic product candidates, such as the risk that any one or more of Sensei’s product candidates will not be successfully developed or commercialized; the risk of delay or cessation of any planned clinical trials of Sensei’s product candidates; the risk that prior results, such as signals of safety, activity or durability of effect, observed from preclinical trials, will not be replicated or will not continue in ongoing or future studies or clinical trials involving Sensei’s product candidates; the risk that Sensei’s product candidates or procedures in connection with the administration thereof will not have the safety or efficacy profile that we anticipate; risks associated with Sensei’s dependence on third-party suppliers and manufacturers, including sole source suppliers, over which we may not always have full control; risks regarding the accuracy of our estimates of expenses, capital requirements and needs for additional financing; and other risks and uncertainties that are described in Sensei’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (SEC) on March 15, 2022 and Sensei’s other Periodic Reports filed with the SEC. Any forward-looking statements speak only as of the date of this press release and are based on information available to Sensei as of the date of this release, and Sensei assumes no obligation to, and does not intend to, update any forward-looking statements, whether as a result of new information, future events or otherwise.

Investor Contact:

Michael Biega

Senior Director, Investor Relations

Sensei Biotherapeutics

Media Contact:

Chris Railey

Ten Bridge Communications


Slide 1

Next Generation Immuno-Oncology Medicines John K. Celebi, MBA President & Chief Executive Officer AUGUST 2022  |  Nasdaq: SNSE Exhibit 99.2

Slide 2

Disclaimer This presentation has been prepared by Sensei Biotherapeutics, Inc. (the “Company,” "we," "us") and is made for informational purposes only. The information set forth herein does not purport to be complete or to contain all of the information you may desire. Statements contained herein are made as of the date of this presentation unless stated otherwise, and neither the delivery of this presentation at any time, nor any sale of securities, shall under any circumstances create an implication that the information contained herein is correct as of any time after such date or that information will be updated or revised to reflect information that subsequently becomes available or changes occurring after the date hereof.  This presentation contains estimates and other statistical data made by independent parties and by us relating to market shares and other data about our industry. This presentation also contains "forward-looking" statements as that term is defined in the Private Securities Litigation Reform Act of 1995 that are based on our management's beliefs and assumptions and on information currently available to management. These forward-looking statements include, without limitation, expectations regarding the development of our product candidates and platforms, the availability of data from our preclinical studies, the timing of selection of product candidates, the timing of IND submissions to the FDA, and our belief that our existing cash and cash equivalents will be sufficient to fund our operations at least into the first quarter of 2025. When used in this presentation, the words and phrases "designed to," "may," "believes," "intends," "seeks," "anticipates," "plans," "estimates," "expects," "should," "assumes," "continues," "could," "will," "future" and the negative of these or similar terms and phrases are intended to identify forward-looking statements. Forward-looking statements involve known and unknown risks, uncertainties and other 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. Risks and uncertainties that may cause actual results to differ materially include uncertainties inherent in the development of therapeutic product candidates, such as preclinical discovery and development, conduct of clinical trials and related regulatory requirements, our reliance on third parties over which we may not always have full control, and other risk and uncertainties that are described in our Annual Report on Form 10-K filed with the SEC on March 15, 2022 and our other Periodic Reports filed with the SEC. Forward-looking statements represent our management's beliefs and assumptions only as of the date of this presentation and include all matters that are not historical facts. Our actual future results may be materially different from what we expect. Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in the forward-looking statements, even if new information becomes available in the future.   Certain information contained in this presentation relates to, or is based on, studies, publications, surveys and other data obtained from third-party sources and the Company's own internal estimates and research. While the Company believes these third-party sources to be reliable as of the date of this presentation, it has not independently verified, and makes no representation as to the adequacy, fairness, accuracy or completeness of, any information obtained from third-party sources. In addition, all of the market data included in this presentation involves a number of assumptions and limitations, and there can be no guarantee as to the accuracy or reliability of such assumptions. Finally, while we believe our own internal research is reliable, such research has not been verified by any independent source.

Slide 3

Positioned to Drive Value with Next Generation Product & Platform Development Two Platforms Generate Broad Pipeline Opportunities TMAb™ ImmunoPhage™ Innovative Pipeline of Differentiated IO mAbs Business Development Strong Cash Position Ended 2Q 2022: $123.7M ** Cash runway into Q1 2025 *Tumor Microenvironment Activated biologics **Consists of cash, cash equivalents and marketable securities

Slide 4

Innovative Pipeline of IO Drugs with Broad Commercial Potential Program (Target) Indication Discovery IND-enabling Phase 1 / 2 Clinical TMAb SNS-101 (VISTA) Solid Tumors SNS-102 (VSIG4) Solid Tumors SNS-103 (ENTPDase1/CD39) Solid Tumors ImmunoPhage SNS-401-NG (Multiple Tumor Antigens) Merkel Cell Carcinoma Multiple Indications

Slide 5

The Modern-Day Challenge in Immuno-Oncology No Survival Benefit 70% Survival Benefit 20-30% ~$30B ~$90B 2020 2026 Global PD-1/PD-L1 Market2 1. Gerber et al., Biochemical Pharmacology 2016 2. Market estimates from PD-1 and PDL-1 Inhibitors Market Size in 2021 – MarketWatch, 360 Research

Slide 6

Two Major Types of Non-Responders to PD-1 Blockade Green = T-cells Purple = tumor Non-Responders T-cells Absent T-cells Inactive or Outside Tumor Responders T-cells Inside Tumor Anti-PD-1 or PD-L1 Treatment Adapted from Van der Woulde-LL, et al, Trends in Cancer, 2017 Hot (inflamed) tumor Cold (excluded) tumor Cold (ignored) tumor

Slide 7

Two Platforms Designed to Unleash Anti-Cancer T-cell Activity ImmunoPhage™ Platform Powerfully self-adjuvanted nanoparticle vaccine designed to drive B cell and T cell responses Multi-antigen vaccine potentially enables personalized approach from “off-the-shelf” components Targets APCs Enhanced through addition of immunostimulatory nanobodies & cytokines TMAb™ (Tumor Microenvironment Activated Biologics) Platform Next-generation tumor activated mAbs Designed to bind only in the low-pH tumor microenvironment Target checkpoints and/or other immune pathways Preclinical data have shown improved PK/PD and toxicity profiles Unleash anti-tumor T-cells Generate anti-tumor T-cells

Slide 8

pH-sensitive Antibodies Selectively Bind Their Targets in the Low-pH Tumor Microenvironment  Antibodies that bind at physiological pH may encounter a “sink” Prevents effective binding at the tumor and may lead to toxicity TMAb antibodies are expected to bypass tissue compartments other than the low-pH tumor microenvironment Goal is to unlock previously undruggable immune targets through potential for improved safety and clinical activity profile pH 7.4 pH 7.4 pH 7.4 pH~ 6 pH~ 6 pH~ 6 TMAb Platform Sensei’s technology identifies pH-sensitive antibodies designed to bind only at the tumor The tumor microenvironment of pH ~6 is lower than physiological pH of 7.4

Slide 9

VISTA: An Emerging Checkpoint Target on Myeloid Cells Target Overview: B7 family ligand Extensive expression on myeloid cells1 correlating with poor survival rates across multiple cancers Novel development program with no approved therapies Large market opportunity Sensei’s Competitive Advantage: Extensive understanding of VISTA biology Unique tumor selective antibody 1. Lines et al. Cancer research vol. 74,7 (2014) 2. Gao et al. Nature medicine vol. 23,5 (2017) VISTA is a Negative Regulator of T cell Function

Slide 10

Increased Understanding of VISTA as a Promising Target to Address the Needs of Patients with Cancer

Slide 11

Key to Unlocking the Power of VISTA Block the pH-dependent binding of VISTA to PSGL-1 on T cells at low pH Selectively bind VISTA at low pH to avoid: target mediated drug disposition (TMDD) on-target/off-tumor side effects Utilize an Fc-competent IgG backbone to engage and activate FcƔR on tumor-infiltrating myeloid cells

Slide 12

VISTA Checkpoint is Activated at the Low pH of the Tumor Microenvironment VISTA’s extracellular domain is uniquely rich in histidines¹ Histidines are protonated at low pH enabling VISTA to distinguish the active (acidic pH) and inactive (neutral pH) PSGL-1 binding interface 1. Johnston et al., Nature 2019 Antibodies that block protonated VISTA histidines interrupt PSGL-1 binding1

Slide 13

SNS-101 Has >600-Fold Selectivity for Active VISTApH6 R [RU] [Vista] – 7.5 nmol – 0.2 nmol ka = 4.59E+06 M-1s-1 Kd = 1.00E-03 s-1 KD = 2.18E-10 M SNS-101 ka = 7.11E+05 M-1s-1 Kd = 1.78E-04 s-1 KD = 2.5E-10 M [Vista] – 15 nmol – 0.2 nmol [Vista] – 7.5 nmol – 0.2 nmol [Vista] – 15 nmol – 0.2 nmol Biophysical characterization demonstrates >600-fold selectivity for VISTA at pH 6.0 Picomolar binding at low pH No significant binding observed at physiological pH (7.4) pH7.4 pH 6.0 pH-dependent “benchmark” pH-independent “benchmark” pH-independent “benchmark” ka = 1.45E+06 M-1S-1 Kd = 2.25E-03 S-1 KD = 1.55E-09 M [Vista] – 15 nmol – 0.2 nmol ka = 4.162E+05 M-1S-1 Kd = 9.27E-05 S-1 KD = 2.23E-10 M [Vista] – 15 nmol – 0.47 nmol pH-dependent “benchmark” R [RU] SITC 2021: Poster titled: Antagonistic pH-selective VISTA antibody SNS-101 potentiates anti-PD-1/PD-L1-induced anti-tumor immunity. pH 6.0 pH 7.4 Monovalent Affinity (KD) [nM]​ 0.218​ 132​ (~No binding)

Slide 14

No Significant Binding of SNS-101 to Monocytes, Neutrophils, NK Cells and T-cells in Whole blood at Physiological pH T-cells NK cells FOB 1.57 FOB 2.0 FOB 1.0 FOB 8.75 FOB 12.4 FOB 1.36 Monocytes FOB 9.9 FOB 13.5 FOB 1.4 FOB 2.2 FOB 2.5 FOB 1.0 Neutrophils CYNO HUMAN FOB 7.4 FOB 8.8 FOB 1.0 Clinical mAb #1 Clinical mAb #2 SNS101 Control FOB 2.0 FOB 2.0 FOB 0.5 Clinical mAb #1 Clinical mAb #2 SNS101 Control FOB 1.66 FOB 1.9 FOB 0.95 FOB 9.7 FOB 10.7 FOB 1.31

Slide 15

SNS-101 Displays a Favorable PK Profile No significant TMDD in human VISTA KI mice Pharmacokinetics of Single Dose 5 mg/kg SNS-101 in VISTA Knock-in Mice Demonstrated a long mean residence time in the blood, indicating a lack of significant target-mediated drug disposition (TMDD) and clearance in non-malignant tissues Week 1 Week 2 Week 3 Week 4 Tumor (MB49) in VISTA KI mice VISTA KI mice No Target WT mice

Slide 16

SNS-101 Demonstrates Activity in a PD-1 Resistant Syngeneic Tumor Model SNS-101* in Combination with Anti-mouse PD-1 Tumor Growth Inhibition Anti-PD-1 + SNS-101 Anti-PD-1 Control Isotype Control 0/10 Anti-PD-1 (1/10) Anti-PD-1 + SNS-101 (5/10) Survival *SNS-101 was grafted on to a mouse IgG2a framework to decrease anti-drug antibody production

Slide 17

SNS-101 VISTA.18 (BMS) KVA12.1 (Kineta) CI-8993; JNJ-61610588 (J&J/Curis) K01401-020; W0180 (Pierre Fabre) HMBD-002 (Hummingbird) Inhibit PSGL-1 Binding Yes Yes unknown Yes unknown No pH Sensitive Binding Yes Yes No No No No Fc Active Yes (IgG1) No (IgG4) Yes (IgG1) Yes (IgG1) N/A No (IgG4) Stage Preclinical Preclinical Preclinical Phase I Phase I Phase I Clinical Data / Notes Demonstrated activity in preclinical models Demonstrated potential for best-in-class safety profile and PK in mouse model IND-enabling studies underway N/A N/A JNJ initiated Phase I study in 2016 12 pts enrolled; initial dose 0.005 mg/kg Only patient treated at 0.3 mg/kg experienced grade 3 CRS-associated encephalopathy; trial was halted Phase I ongoing Not published Not published SNS-101 Is a Differentiated Anti-VISTA Antibody TMAb Platform Johnston et al, Nature, 2019; Kineta website; Snyder et al, AACR Annual Meeting 2016; Pierre Fabre website; Hummingbird website; Thakkar et al, J of Immunother Cancer, 2022

Slide 18

VSIG4 Plays a Critical Suppressive Role in T-cell Activation B7 family related protein Expressed primarily on macrophages and inhibits T-cell activation As of August 2022, Sensei has: Identified 8 parental antibodies for further optimization; and Identified novel VSIG4 receptors on primary T-cells by Hi-Res proteomics, which are currently in verification stage   Select product candidate & initiate IND-enabling studies in 2023 Adapted from Zang et al., J Clin Invest. 2006

Slide 19

Cell Surface Expressed VSIG-4 Suppresses Primary Human T-cell Activation Zang et al. J Clin Invest. 2006;116(10):2590-2593 Cryopreserved PBMCs CD4+ T cell Purification IFNg Proliferation Cell Isolation Day 3 Activation-induced Expansion No Stimulation Control aCD3 + aCD28 Day 4 Day 3- IFNg Production Day 4- Proliferation T cells, HEK, Stim. + T cells, No HEK, Stim. + T cells, No Stimulation Cell Trace Violet 3/3 Donors Responsive 1) HEK 2) HEK VSIG-4 VSIG-4 Division Index T cells, HEK VSIG-4, Stim. + Isotype Control VSIG-4 Donor 2111403021(CE0007305) pg/mL

Slide 20

ENTPDase1 (CD39) is the Rate Limiting Enzyme in the Production of Immunosuppressive Adenosine ATP AMP Adeno-sine Figure adapted from: Moesta et al, Nat Rev Immunol. 2020; 20 (12)​ Primary function is conversion of extracellular ATP / ADP to adenosine​, which exerts immunosuppressive properties through binding to A2a/A2b receptors Expressed on various immune cells in both tumors and normal tissues Development of a TMAb antibody has potential for improved safety and PK profile compared to competitor CD39 mAbs First set of parental antibodies expected August 2022 Blocking CD39 leads to: Immune Activation

Slide 21

Designed to Generate Strong Antibody and T-cell Responses ImmunoPhage™ Platform Viral DNA (self-adjuvant) Target antigen The ImmunoPhage™ bacteriophage is an icosahedron with a tail. This configuration can be viewed as an activating signal to the immune system Bacteriophage virus is engineered and manufactured with both antigen and immune stimulatory viral DNA

Slide 22

Phortress: Proprietary Library of Personalized Vaccine Cocktails with Off-the-Shelf ImmunoPhage “Ingredients” These “cocktails” are defined by the disease or patient genetics Combinations are customized to cover multiple epitopes, protein domains or targets Each ImmunoPhage is pre-manufactured to target a discrete antigen Immunologically reactive B-and T-cell target epitopes

Slide 23

Routine Biopsy Tumor Sequencing Personalized yet Off-the-shelf ImmunoPhage Cocktail Neoantigen Prediction Neoantigen ImmunoPhage️ Manufacturing ImmunoPhage Injection Including Neoantigens Clinical biopsy of tumor as input material Tumor DNA Tumor RNA Normal DNA Assemble a personalized cocktail from off-the-shelf TAA ImmunoPhage for administration Identify additional tumor specific neoantigens Engineer novel ImmunoPhages️ expressing distinct tumor specific epitopes Deliver neoantigen ImmunoPhage️ cocktail for administration and add neoantigen phages to bank for future use Personalized Immunotherapy Approach Could Accelerate Speed to Treatment High speed and low cost-of-goods of ImmunoPhage potentially allows a broader array of antigens  Off-the-Shelf + Patient-specific Neoantigen Therapy Personalized yet Off-the Shelf TAA Therapy

Slide 24

SNS-101 (anti-VISTA) Q3 2022: Non-Human Primate (NHP) PK data Q3 2022: Cytokine Release Data 1H 2023: IND filing SNS-102 (anti-VSIG4) 2023: Select product candidate / initiate IND-enabling studies SNS-103 (anti-ENTPDase1/CD39) 2023: Select product candidate Expected Program Milestones

Slide 25

Proven Team With Deep Experience Patrick Gallagher Acting Chief Business Officer Elisabeth Colunio VP, Human Resources Edward van der Horst, Ph.D. SVP, TMAb Antibodies John Celebi, MBA President and CEO Robert Pierce, M.D. Chief R&D Officer Erin Colgan Chief Financial Officer HansPeter Waldner,Ph.D. SVP, Cancer Immunology Christopher Gerry, J.D. VP, General Counsel

Slide 26

HQ: 451 D St, Unit 710 , Boston, MA 02210 / MD: 1405 Research Blvd, Suite 125, Rockville, MD 20850