Sensei Biotherapeutics (NASDAQ: SNSE) 2025 loss narrows, lands $200M

Rhea-AI Filing Summary

Sensei Biotherapeutics reported full-year 2025 results and highlighted its strategic shift following the Faeth Therapeutics acquisition and a $200 million private placement. PIKTOR, an all-oral combination targeting the PI3K/AKT/mTOR pathway, is now the lead program in endometrial and HR+/HER2- advanced breast cancer.

Cash, cash equivalents and marketable securities were $21.2 million as of December 31, 2025. R&D expenses fell to $11.0 million from $18.6 million and G&A to $11.3 million from $13.0 million, helping narrow net loss to $21.1 million, or $(16.72) per share, from $30.2 million, or $(24.01) per share.

Positive

• $200 million private placement and Faeth acquisition strengthen Sensei Biotherapeutics’ balance sheet and add PIKTOR, a multi-node PI3K/AKT/mTOR inhibitor, as the new lead oncology program.
• Substantial operating expense reduction in 2025, with R&D down to $11.0 million from $18.6 million and G&A down to $11.3 million from $13.0 million, narrowed net loss to $21.1 million from $30.2 million.

Negative

• None.

Insights

Biotech equity analyst

Large financing and pipeline pivot, with meaningfully lower 2025 cash burn.

Sensei Biotherapeutics reports a full-year 2025 net loss of $21.1 million, improved from $30.2 million in 2024, as R&D and G&A expenses declined sharply. Total operating expenses dropped to $22.3 million from $32.6 million, indicating substantial cost discipline.

The company completed its acquisition of Faeth Therapeutics and secured a $200 million private placement, while making PIKTOR its lead program. PIKTOR is described as a multi-node inhibitor of the PI3K/AKT/mTOR pathway, now being advanced in endometrial and HR+/HER2- advanced breast cancer trials.

Management states that the financing, together with existing cash, is expected to support PIKTOR through key clinical milestones, including topline data from the Phase 2 endometrial cancer study and a planned Phase 1b breast cancer study by year-end 2026. Subsequent company filings may detail how the combined cash position evolves as these trials progress.

8-K Event Classification

2 items: 2.02, 9.01

2 items

Item 2.02 Results of Operations and Financial Condition Financial

Disclosure of earnings results, typically an earnings press release or preliminary financials.

Item 9.01 Financial Statements and Exhibits Exhibits

Financial statements, pro forma financial information, and exhibit attachments filed with this report.

Understanding 8-K Material Events →

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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): March 30, 2026

Sensei Biotherapeutics, Inc.

(Exact Name of Registrant as Specified in its Charter)

Delaware		001-39980		83-1863385
(State or Other Jurisdiction of Incorporation)		(Commission File Number)		(IRS Employer Identification No.)
1405 Research Blvd, Suite 125
Rockville, MD				20850
(Address of Principal Executive Offices)				(Zip Code)
451 D Street, Suite 710
Boston, MA				02210
(Former 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 symbol		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 March 30, 2026, Sensei Biotherapeutics, Inc. issued a press release announcing its financial results for the full year ended December 31, 2025. A copy of the press release is attached hereto as Exhibit 99.1.

The information in Item 2.02 and the exhibit attached hereto is 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 Number		Exhibit Description
99.1		Press Release of Sensei Biotherapeutics, Inc., dated March 30, 2026
104		The cover page from this Current Report on Form 8-K, formatted in Inline XBRL

2

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: March 30, 2026						/s/ Christopher W. Gerry
						Christopher W. Gerry
						President and General Counsel

3

Exhibit 99.1

Sensei Biotherapeutics Reports Full Year 2025 Financial Results and Provides Corporate Update

Faeth acquisition adds PIKTOR, an all-oral combination product candidate targeting multiple nodes of the PI3K/AKT/mTOR pathway

$200 million private placement supports key clinical milestones in endometrial and breast cancer

BOSTON, Mass., March 30, 2026 — Sensei Biotherapeutics, Inc. (Nasdaq: SNSE) today reported financial results for the full year ended December 31, 2025, following its previously announced acquisition of Faeth Therapeutics and concurrent $200 million private placement. The financing, together with the Company’s cash on hand, is expected to support advancement of PIKTOR through key clinical milestones, including topline data readouts from both the ongoing Phase 2 trial in advanced endometrial cancer (Study FTH-PIK-201) and the planned Phase 1b trial in HR+/HER2- advanced breast cancer (Study FTH-PIK-101).

Acquired through the Faeth transaction, PIKTOR is now Sensei’s lead program. The investigational, proprietary, all-oral combination of serabelisib and sapanisertib is designed to inhibit multiple nodes of the PI3K/AKT/mTOR pathway through PI3K-alpha and dual mTORC1/2 targeting.

“2025 was a year of focus and discipline for Sensei, and with the addition of Faeth and injection of new capital, we are entering 2026 with a clear path forward,” said Christopher Gerry, President & General Counsel of Sensei Biotherapeutics. “We are now focused on advancing PIKTOR through key clinical milestones, including topline data from the ongoing Phase 2 trial in advanced endometrial cancer and initiation of the planned Phase 1b trial in HR+/HER2- advanced breast cancer, both expected by year-end 2026.”

“The data to date suggest PIKTOR may achieve more comprehensive pathway suppression than single-node approaches, with an emerging tolerability profile that compares favorably to existing therapies, highlighting its potential to address significant unmet need in multiple solid tumor indications,” said Anand Parikh, Chief Operating Officer of Sensei Biotherapeutics. “We are focused on disciplined execution as we advance PIKTOR through clinical trials in endometrial and breast cancer, with additional opportunities in ovarian and lung cancer.”

Full Year 2025 Financial Results

Cash Position: Cash, cash equivalents and marketable securities were $21.2 million as of December 31, 2025 as compared to $41.3 million as of December 31, 2024.

Research and Development (R&D) Expenses: R&D expenses were $11.0 million for the year ended December 31, 2025, compared with $18.6 million for the year ended December 31, 2024. The decrease in R&D expenses was primarily attributable to reduced costs across personnel, facilities, lab supplies, clinical trials, and manufacturing.

General and Administrative (G&A) Expenses: G&A expenses were $11.3 million for the year ended December 31, 2025, compared to $13.0 million for the year ended December 31, 2024. The decrease in G&A expense was primarily attributable to lower personnel costs, partially offset by higher restructuring costs in 2025 and higher consulting costs.

Net Loss: Net loss was $21.1 million, or $(16.72) per basic and diluted share, for the year ended December 31, 2025, compared with a net loss of $30.2 million, or $(24.01) per basic and diluted share, for the year ended December 31, 2024.

Weighted-average common shares outstanding, basic and diluted, were 1,260,772 for the year ended December 31, 2025, compared with 1,255,776 for the year ended December 31, 2024.

Condensed Statements of Operations

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

		Year Ended 2025				Year Ended 2024
Operating expenses:
Research and development		$	10,960			$	18,627
General and administrative			11,328				13,036
Long-lived asset impairment			—				951
Total operating expenses			22,288				32,614
Loss from operations			(22,288	)			(32,614	)
Total other income			1,203				2,457
Net loss		$	(21,085	)			(30,157	)
Net loss attributable to common stockholders			(21,085	)			(30,157	)
Net loss per share, basic and diluted		$	(16.72	)		$	(24.01	)
Weighted-average common shares outstanding, basic and diluted			1,260,772				1,255,776

Selected Condensed Balance Sheet Data

(Unaudited, in thousands)

		December 31, 2025				December 31, 2024
Cash and cash equivalents		$	8,668			$	9,994
Marketable securities			12,516				31,341
Total assets			22,902				45,361
Total liabilities			4,310				6,975
Total stockholders’ equity			18,592				38,386

About Sensei Biotherapeutics

Sensei Biotherapeutics, Inc. (Nasdaq: SNSE) is a clinical-stage biotechnology company focused on improving outcomes for cancer patients through multi-node inhibition of critical oncogenic pathways. Following the acquisition of Faeth Therapeutics, Sensei’s lead program is PIKTOR, an investigational multi-node inhibitor of the PI3K/AKT/mTOR pathway in development for endometrial and breast cancer. Sensei is also completing a Phase 1/2 trial of solnerstotug, its V-domain Ig suppressor of T cell activation (VISTA) inhibitor, in patients with advanced solid tumors. Sensei intends to use its website as a means of disclosing material non-public information and for complying with its disclosure obligations under Regulation FD. For more information, please visit www.senseibio.com and follow the company on X @SenseiBio and LinkedIn.

Cautionary Note Regarding Forward-Looking Statements

Certain statements in this press release, other than purely historical information, may constitute “forward-looking statements” within the meaning of the federal securities laws, including for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995, concerning Sensei and Faeth, including the acquisition of Faeth by Sensei (the “Transaction”) and other matters. These forward-looking statements include, but are not limited to, express or implied statements relating to the company’s expectations, hopes, beliefs, intentions or strategies regarding the future including, without limitation, statements regarding: the Transaction, including the expected effects, perceived benefits or opportunities and related timing with respect thereto; expectations regarding or plans for the company’s pipeline, including its ongoing clinical trials, research and development programs and the expected timing for key milestones; the potential benefits of PIKTOR; and expectations regarding the use of proceeds from the concurrent financing and cash runway expectations therefrom, including such proceeds funding the company through key clinical milestones. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. The words “opportunity,” “potential,” “milestones,” “pipeline,” “can,” “goal,” “aim,” “strategy,” “target,” “seek,” “anticipate,” “achieve,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “might,” “plan,” “possible,” “predict,” “project,” “should,” “will,” “would” and similar expressions (including the negatives of these terms or variations of them) may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. These forward-looking statements are based on current expectations and beliefs concerning future developments and their potential effects. There can be no assurance that future developments affecting the company or the Transaction will be those that have been anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond the company’s control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to those uncertainties and factors described under the heading “Risk Factors” and “Summary of Risk Factors” in the company’s Annual Report on Form 10-K, filed with the Securities and Exchange Commission (the “SEC”) on March 30, 2026, as well as discussions of potential risks, uncertainties, and other important factors included in other filings by the company from time to time, as well as risk factors associated with companies, such as Faeth, that operate in the biotechnology industry. Should one or more of these risks or uncertainties materialize, or should any of the company’s assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. Nothing in this press release should be regarded as a representation by any person that the forward-looking statements set forth herein will

be achieved or that any of the contemplated results of such forward-looking statements will be achieved. You should not place undue reliance on forward-looking statements in this press release, which speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. The company does not undertake or accept any duty to release publicly any updates or revisions to any forward-looking statements. This press release does not purport to summarize all of the conditions, risks and other attributes of an investment in the company.

Investor Contact:

Stephanie Ascher, Precision AQ

Stephanie.ascher@precisionaq.com

Media Contact:

Patrick Schmidt, Consort Partners

senseibio@consortpartners.com

FAQ

How did Sensei Biotherapeutics (SNSE) perform financially in 2025?

Sensei Biotherapeutics reported a 2025 net loss of $21.1 million, or $(16.72) per share. This compares with a 2024 net loss of $30.2 million, or $(24.01) per share, reflecting lower operating expenses across research, development, and general and administrative functions.

What is PIKTOR and why is it important to Sensei Biotherapeutics?

PIKTOR is Sensei’s new lead program, acquired through Faeth Therapeutics. It is an investigational, all-oral combination of serabelisib and sapanisertib targeting multiple nodes of the PI3K/AKT/mTOR pathway, with development focused on advanced endometrial and HR+/HER2- advanced breast cancers.

What major financing did Sensei Biotherapeutics complete alongside the Faeth acquisition?

Sensei Biotherapeutics completed a $200 million private placement concurrent with the acquisition of Faeth Therapeutics. The company states that this financing, together with cash on hand, is expected to support PIKTOR through key clinical milestones in endometrial and breast cancer studies.

How did Sensei Biotherapeutics’ 2025 R&D and G&A expenses change versus 2024?

In 2025, R&D expenses were $11.0 million, down from $18.6 million in 2024. G&A expenses were $11.3 million, compared with $13.0 million in 2024. Management attributes these declines mainly to lower personnel and other operating costs.

What was Sensei Biotherapeutics’ cash and investment position at year-end 2025?

As of December 31, 2025, Sensei Biotherapeutics held $8.7 million in cash and cash equivalents and $12.5 million in marketable securities. Total assets were $22.9 million, with total liabilities of $4.3 million and stockholders’ equity of $18.6 million.

What clinical milestones does Sensei Biotherapeutics expect for PIKTOR by year-end 2026?

The company expects topline data from an ongoing Phase 2 trial in advanced endometrial cancer and initiation of a planned Phase 1b trial in HR+/HER2- advanced breast cancer, with both milestones anticipated by year-end 2026.

Filing Exhibits & Attachments

5 documents

Press Releases

• EX-99.1 EX-99.1 29.2 KB

Other Documents

• EX-101 XBRL TAXONOMY EXTENSION SCHEMA 3.4 KB
• EX-101 XBRL TAXONOMY EXTENSION DEFINITION LINKBASE 15.8 KB
• EX-101 XBRL TAXONOMY EXTENSION LABEL LINKBASE 26.1 KB
• EX-101 XBRL TAXONOMY EXTENSION PRESENTATION LINKBASE 16.5 KB