# EDGAR Filing Document

**Accession Number:** 0001829802
**File Stem:** 0001193125-25-173043
**Filing Date:** 2025-8
**Character Count:** 16315
**Document Hash:** 8412c197c5dbb914d767d3d21bb5a942
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-25-173043.hdr.sgml**: 20250805

**ACCESSION NUMBER**: 0001193125-25-173043

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 13

**CONFORMED PERIOD OF REPORT**: 20250805

**ITEM INFORMATION**: Results of Operations and Financial Condition

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20250805

**DATE AS OF CHANGE**: 20250805

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Sensei Biotherapeutics, Inc.
- **CENTRAL INDEX KEY:** 0001829802
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-39980
- **FILM NUMBER:** 251182812

**BUSINESS ADDRESS:**
- **STREET 1:** 1405 RESEARCH BLVD, SUITE 125
- **CITY:** ROCKVILLE
- **STATE:** MD
- **ZIP:** 20850
- **BUSINESS PHONE:** (240) 243-8000

**MAIL ADDRESS:**
- **STREET 1:** 1405 RESEARCH BLVD, SUITE 125
- **CITY:** ROCKVILLE
- **STATE:** MD
- **ZIP:** 20850

?xml version='1.0' encoding='ASCII'? 8-K

### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

### FORM 8-K

#### CURRENT REPORT

#### Pursuant to Section 13 or 15(d)

#### of the Securities Exchange Act of 1934

#### Date of Report (Date of earliest event reported): August 5, 2025

## Sensei Biotherapeutics, Inc.

#### (Exact Name of Registrant as Specified in its Charter)

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-39980** | **83-1863385** |
| **(State or Other Jurisdiction**<br> **of Incorporation)** | **(Commission**<br> **File Number)** | **(IRS Employer**<br> **Identification No.)** |
| **1405 Research Blvd, Suite 125**<br> **Rockville, MD** | **1405 Research Blvd, Suite 125**<br> **Rockville, MD** | **20850** |
| **(Address of Principal Executive Offices)** | **(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** | **Trading**<br> **symbol** | **Name of each exchange**<br> **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. ☐

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---

| | |
|:---|:---|
| **Item 2.02** | **Results of Operations and Financial Condition.**  |

---

On August 5, 2025, Sensei Biotherapeutics, Inc. issued a press release announcing its financial results for the quarter ended June 30, 2025. A copy of the press release is attached hereto as Exhibit 99.1.

The information in this Item 2.02 and the exhibit 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

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| | |
|:---|:---|
| **Exhibit<br>Number** | **Exhibit Description** |
| 99.1 | [Press Release of Sensei Biotherapeutics, Inc., dated August 5, 2025](d46736dex991.htm) |
| 104 | The cover page from this Current Report on Form 8-K, formatted in Inline XBRL |

---

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#### SIGNATURES
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 5, 2025 | /s/ Christopher W. Gerry |
|  | Christopher W. Gerry |
|  | General Counsel and Secretary |

---

## Exhibit 99.1

**Exhibit 99.1** 

**Sensei Biotherapeutics Reports Second Quarter 2025 Financial Results and Provides Corporate Update** 

*- Full data for Phase 1/2 dose expansion cohort expected by year-end 2025 -* 

*- Cash runway into the second quarter of 2026 -* 

**BOSTON, MA – August 5, 2025–** Sensei Biotherapeutics, Inc. (Nasdaq: SNSE), a clinical stage biotechnology company focused on the discovery and development of next-generation therapeutics for cancer patients, today reported financial results for the second quarter 2025, and provided a corporate update.

"The second quarter was a key inflection point for Sensei, as we now transition from early response-focused readouts to longer-term and commercially relevant efficacy signals with the maturity of the data from our Phase 1/2 study of solnerstotug," said John Celebi, President and CEO of Sensei. "Solnerstotug has demonstrated a favorable safety profile and in combination with cemiplimab has not demonstrated significant additional toxicity relative to what is typically observed with PD-(L)1 monotherapy, which we believe could translate into better patient adherence and more meaningful long-term outcomes with continued treatment, as well as physician preference and payor interest."

"As we look to next steps in the clinical advancement of solnerstotug, we envision multiple Phase 2 studies across PD-(L)1 resistant tumor types, aligned with unmet need and commercial potential. We view these differentiated opportunities as potentially derisking overall, while positioning solnerstotug for multiple indications in high-value immunotherapy segments of the ~$50 billion PD-(L)1 market," added Mr. Celebi. "We continue to work on finalizing the Phase 2 strategy for solnerstotug, which will be strongly influenced by the full dose expansion dataset we plan to present later this year."

Solnerstotug (formerly SNS-101) is a conditionally active antibody designed to selectively target the immune checkpoint VISTA (V-domain Ig suppressor of T cell activation) within the tumor microenvironment. VISTA is implicated in numerous cancer indications and its expression correlates with low survival rates.

Sensei's ongoing multi-center Phase 1/2 clinical trial is evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of solnerstotug as both a monotherapy and in combination with Regeneron's PD-1 inhibitor Libtayo<sup>®</sup> (cemiplimab) in patients with advanced solid tumors.

**Clinical Program Highlights:** 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Full dose expansion data, including 6-month progression free survival
(PFS), from the Phase 1/2 study continues to be expected by year-end 2025.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Enrollment in the Phase 1/2 dose expansion cohort is complete with a total of 64 patients, including:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 10 "cold" MSS CRC patients in the monotherapy arm

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• 54 patients in the cemiplimab combination arm consisting of 10 "cold" MSS CRC patients and 44
"hot" tumor patients. 41/44 patients in the "hot" tumor cohort had received and progressed on a prior PD-(L)1 inhibitor.

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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• <u>On March 27<sup>th</sup></u>, Sensei announced favorable preliminary
clinical data in PD-(L)1 resistant patients from the dose expansion stage of its ongoing Phase 1/2 trial, demonstrating favorable activity in patients with PD-(L)1 resistant "hot" tumors. Solnerstotug continued to be well tolerated, with no dose-limiting toxicities, and the majority of AEs Grade 1 or 2 in severity.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• A replay of the March 2025 webcast related to the preliminary data, featuring study investigator Dr. Shiraj
Sen, is available on the <u>Sensei website</u>.

**Corporate Updates:** 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• On July 30<sup>th</sup>, the Company announced that clinical data from
the dose expansion cohort of the Phase 1/2 trial of solnerstotug alone and in combination with cemiplimab will be presented in a mini oral session at the European Society for Medical Oncology (ESMO) Congress 2025, being held October 17-21, 2025 in Berlin, Germany.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• Sensei regains Nasdaq compliance following the 1-for-20 reverse split of its common stock, which became effective at 5:00 p.m. ET on June 16th, and subsequent 10-day bid price remaining above $1.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;• On April 7<sup>th</sup>, John Celebi participated in a panel discussion
titled "New Radiotherapy and Targeted Therapy Approaches" at the Canaccord Genuity Horizons in Oncology Virtual Conference. The panel focused on emerging innovations in cancer treatment and Sensei's approach to selectively modulating
the tumor microenvironment.

**Second Quarter 2025 Financial Results** 

**Cash Position:** Cash, cash equivalents and marketable securities were $28.6 million as of June 30, 2025, as compared to $41.3 million as of December 31, 2024. Sensei expects its current cash balance to fund operations into the second quarter of 2026.

**Research and Development (R&D) Expenses:** R&D expenses were $2.5 million for the quarter ended June 30, 2025, compared to $4.6 million for the quarter ended June 30, 2024. The decrease in R&D expenses was primarily attributable to lower personnel and facilities costs, and reduced manufacturing cost.

**General and Administrative (G&A) Expenses:** G&A expenses were $2.7 million for the quarter ended June 30, 2025, compared to $3.2 million for the quarter ended June 30, 2024. The decrease in G&A expense was primarily attributable to lower personnel costs.

**Net Loss:** Net loss was $4.9 million for the quarter ended June 30, 2025, compared to $7.1 million for the quarter ended June 30, 2024.

**About Sensei Biotherapeutics**

Sensei Biotherapeutics (Nasdaq: SNSE) is a clinical stage biotechnology company focused on the discovery and development of next-generation therapeutics for cancer patients. Through its TMAb<sup>™</sup> (Tumor Microenvironment Activated biologics) platform, Sensei develops conditionally active therapeutics designed to disable immunosuppressive signals or activate immunostimulatory signals selectively in the tumor microenvironment to unleash T cells against tumors. Sensei's lead product candidate is solnerstotug, a conditionally active antibody designed to block the V-domain Ig suppressor of T cell activation (VISTA) checkpoint selectively within the low pH tumor microenvironment, where VISTA acts as a suppressor of T cells by binding the receptor PSGL-1. For more information, please visit www.senseibio.com, and follow the company on X @SenseiBio and LinkedIn.

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**Condensed Statements of Operations** 

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

---

| | | |
|:---|:---|:---|
|  | **Three Months Ended**<br>**June 30,** | **Three Months Ended**<br>**June 30,** |
|  | **2025** | **2024** |
|  Operating expenses: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Research and development | $2533 | $4584 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; General and administrative | 2673 | 3203 |
|  Total operating expenses | 5206 | 7787 |
|  Loss from operations | (5206) | (7787) |
|  Total other income | 270 | 645 |
|  Net loss | (4936) | (7142) |
|  Net loss attributable to common stockholders | (4936) | (7142) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Net loss per share, basic and diluted | $(3.91) | $(5.69) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Weighted-average common shares outstanding, basic and diluted | 1260867 | 1255145 |

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**Selected Condensed Balance Sheet Data** 

**(Unaudited, in thousands)** 

---

| | | |
|:---|:---|:---|
|  | **June 30,<br>2025** | **December 31,<br>2024** |
|  Cash and cash equivalents | $12557 | $9994 |
|  Marketable securities | 16071 | 31341 |
|  Total assets | 31783 | 45361 |
|  Total liabilities | 4469 | 6975 |
|  Total stockholders' equity | 27314 | 38386 |

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**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, the timing of Sensei's Phase 1/2 clinical trial of solnerstotug, including reporting of data therefrom, the planning and strategy for Phase 2 clinical studies of solnerstotug, and its belief that its existing cash and cash equivalents will be sufficient to fund its operations into the second quarter of 2026. 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

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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 studies and clinical 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 Sensei anticipates; risks associated with Sensei's dependence on third-party suppliers and manufacturers, including sole source suppliers, over which Sensei may not always have full control; risks regarding the accuracy of Sensei's estimates of expenses, capital requirements and needs for additional financing; and other risks and uncertainties that are described in Sensei's Quarterly Report on Form 10-Q filed with the U.S. Securities and Exchange Commission (SEC) on August 5, 2025 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 and Media Contact:** 

Joyce Allaire

LifeSci Advisors

<u>Jallaire@lifesciadvisors.com</u>