PLSE: First‑in‑Human nPulse Study Shows 100% Posterior Box Isolation

Rhea-AI Filing Summary

Pulse Biosciences reported late-breaking first‑in‑human feasibility results for its nPulse™ Cardiac Surgical System. The study has treated 44 patients across three investigators, with an initial cohort of 24 patients evaluated by electroanatomical mapping about ~3 months after ablation. Key clinical outcomes: posterior box isolations were acutely successful in 100% of cases in the high‑dose cohort; pulmonary vein isolation (PVI) success per vein at ~3 months was 94% (63 of 67); average total ablation time was 50 seconds with an average of 13 applications. No esophageal or phrenic nerve damage and no ablation‑related severe or major adverse events were reported. The company attached a press release as Exhibit 99.1 describing presentation of these results at the European Association for Cardio‑Thoracic Surgery annual meeting.

Positive

• 94% PVI success per vein at ~3 months (63/67)
• 100% acute posterior box isolation in the high‑dose cohort
• No esophageal or phrenic nerve injuries reported
• No ablation‑related severe or major adverse events reported
• Average total ablation time 50 seconds with 13 applications

Negative

• Limited sample size: only 24 patients had ~3‑month electroanatomical mapping
• Short follow‑up of approximately ~3 months, limiting durability assessment
• Early feasibility stage: results require confirmation in larger, multi‑center studies
• No financial impact or regulatory pathway disclosed in the filing

Insights

Clinical Affairs Specialist

Early safety and durability signals appear favorable in a small first‑in‑human cohort.

The study reports 94% PVI success per vein at roughly ~3 months and 100% acute posterior box isolation in the high‑dose cohort, suggesting the device can achieve electrical isolation efficiently with an average 50‑second total ablation time and 13 applications. The absence of esophageal or phrenic nerve injuries and no reported severe or major ablation‑related adverse events are positive safety signals.

These results depend on limited patient numbers (24 with mapping data, 44 treated overall) and short follow‑up; confirmatory larger studies and longer‑term durability data beyond ~3 months are needed to assess sustained efficacy and rare adverse events within a typical clinical adoption timeline of 12–36 months.

Cardiovascular MedTech Analyst

Operational metrics indicate fast procedures, which may reduce procedure time if replicated.

The reported 50‑second average ablation time and 13 applications imply a compact energy delivery profile that could shorten case duration compared with conventional methods; this could influence hospital workflow and cost if validated in broader cohorts. The presentation at a major society meeting supports peer engagement and visibility.

Key dependencies are scalability of results across more operators and centers, reimbursement acceptance, and demonstration of long‑term durability past ~3 months. Watch for planned pivotal study designs, enrollment timelines, and any regulatory submissions in the next 12–24 months.

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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): October 10, 2025

Pulse Biosciences, Inc.
(Exact Name of Registrant as Specified in Its Charter)
Delaware	001-37744	46-5696597
(State or Other Jurisdiction of Incorporation)	(Commission File Number)	(IRS Employer Identification No.)
601 Brickell Key Drive, Suite 1080
Miami, Florida 33131
(Address of Principal Executive Offices) (Zip Code)
510-906-4600
(Registrant’s Telephone Number, Including Area Code)

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 (see General Instruction A.2. below):

☐ 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	Trading Symbol(s)	Name of Each Exchange on Which Registered
Common stock, $0.001 par value per share	PLSE	The Nasdaq Stock 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 8.01 Other Events.

On October 10, 2025, Pulse Biosciences, Inc. (the “Company”) issued a press release announcing late-breaking clinical study results from its nPulse™ Cardiac Surgical System first-in-human feasibility study. To date, 44 patients have been treated by three investigators in the study. In the initial cohort, twenty-four patients have had the ablation effectiveness and durability evaluated by electroanatomical mapping at approximately three months post the ablation procedure. Initial cohort study results include:

●		All (100%) posterior box isolations were acutely successful in the high-dose cohort
●		Success rate of PVI (per vein) at ~3 months was 94% (63/67)
●		Average total ablation time of 50 seconds with average number of 13 applications
●		No reports of esophageal or phrenic nerve damage
●		No ablation-related severe or major adverse events

A copy of the press release related to the matters set forth herein is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number	Description
99.1	Press Release issued by Pulse Biosciences, Inc. dated October 10, 2025 - Pulse Biosciences Announces Presentation of Late-Breaking Data from the nPulse™ Cardiac Surgical System First-In-Human Feasibility Study at the 39th European Association for Cardio-Thoracic Surgery Annual Meeting
104	Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURE

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, thereunto duly authorized.

	PULSE BIOSCIENCES, INC.
Date: October 10, 2025	By:	/s/ Paul A. LaViolette
		Paul LaViolette
		Chief Executive Officer (Principal Executive Officer)

FAQ

What results did Pulse Biosciences (PLSE) report from the nPulse first‑in‑human study?

The company reported 94% PVI success per vein at ~3 months (63/67) and 100% acute posterior box isolation in the high‑dose cohort.

How many patients were treated in the study referenced by PLSE?

A total of 44 patients have been treated, with 24 patients in the initial cohort evaluated by electroanatomical mapping at ~3 months.

Were there any safety issues reported in the PLSE filing?

No esophageal or phrenic nerve damage and no ablation‑related severe or major adverse events were reported.

What procedural metrics did PLSE disclose for the nPulse system?

The company reported an average total ablation time of 50 seconds and an average of 13 applications per procedure.

Has Pulse Biosciences provided long‑term durability data?

No. The filing reports mapping data at approximately ~3 months; longer‑term durability beyond that period was not disclosed.