New nPulse atrial fibrillation data for Pulse Biosciences (NASDAQ: PLSE)

Filing Impact

(High)

Filing Sentiment

(Neutral)

Form Type

8-K

Rhea-AI Filing Summary

Pulse Biosciences, Inc. furnished an update on its first-in-human clinical study of the nPulse Cardiac Catheter System for atrial fibrillation, highlighting sustained procedure success and efficiency metrics from a multicenter feasibility study in Europe.

At Heart Rhythm 2026, investigators reported 100% procedural success at 6 months in 95 evaluable patients and 96% procedural success at one year in 51 evaluable patients, with a 90% Kaplan-Meier estimate of freedom from AF/AFL/AT at one year. Among 177 treated patients, serious adverse events related to the primary safety endpoint occurred in 1.7% of subjects. The company also posted an updated investor presentation and a detailed press release with these results.

Insights

Early nPulse AF data show high durability and low serious events but remain feasibility-stage.

Pulse Biosciences reported updated feasibility data for its nPulse Cardiac Catheter System in atrial fibrillation. In the 5‑second ablation cohort, procedural success remained high, with 100% success at 6 months in 95 evaluable patients and 96% at one year in 51 evaluable patients.

The study also showed a 90% Kaplan–Meier estimate of freedom from AF/AFL/AT at one year, alongside short average procedure times and low fluoroscopy exposure. Across 177 treated patients, 1.7% (3/177) experienced serious adverse events related to the primary safety endpoint, which is a relatively low rate for early-stage ablation technology.

These findings suggest the non-thermal nsPFA approach can deliver durable pulmonary vein isolation with efficient workflows in a multicenter European setting. However, results come from an ongoing feasibility study, and future regulatory, larger-scale, and longer-term data will be important to understand potential commercial impact.

8-K Event Classification

2 items: 7.01, 9.01

2 items

Item 7.01 Regulation FD Disclosure Disclosure

Material non-public information disclosed under Regulation Fair Disclosure, often investor presentations or guidance.

Item 9.01 Financial Statements and Exhibits Exhibits

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

Key Figures

Procedural success at 6 months: 100% (95/95 evaluable patients) Procedural success at 12 months: 96% (51/53 evaluable patients) Freedom from AF/AFL/AT at 1 year: 90% Kaplan-Meier estimate +5 more

8 metrics

Procedural success at 6 months 100% (95/95 evaluable patients) Holter-confirmed success at 6 months in feasibility study

Procedural success at 12 months 96% (51/53 evaluable patients) Holter-confirmed success at one year

Freedom from AF/AFL/AT at 1 year 90% Kaplan-Meier estimate Durability of rhythm control at one year

Patients treated 177 patients Total cohort in ongoing feasibility study

Serious adverse event rate 1.7% (3/177 subjects) Events related to primary safety endpoint

Total procedure time 60.2 ± 27.7 minutes Average total procedure duration

Fluoroscopy time 9.4 ± 5.9 minutes Average fluoroscopy exposure per procedure

Left atrial dwell time 18.6 ± 13.0 minutes Average left atrial dwell time

Key Terms

first-in-human clinical study, Kaplan-Meier estimate, Nanosecond Pulsed Field Ablation, pulmonary vein isolation, +2 more

6 terms

first-in-human clinical study medical

"additional key findings from the first-in-human clinical study of its nPulse Cardiac Catheter System"

A first-in-human clinical study is the initial test of a new drug, vaccine, or medical device in human volunteers after laboratory and animal work; it checks basic safety, dose ranges, and how the body responds. Investors watch these studies like a company’s first product demo — positive safety and clear biological effects reduce risk and can unlock larger, more expensive trials or partner deals, while setbacks often lower a program’s commercial value.

Kaplan-Meier estimate medical

"Sustained 90% Kaplan-Meier estimate of freedom from AF/AFL/AT at one year"

Nanosecond Pulsed Field Ablation medical

"using proprietary Nanosecond Pulsed Field Ablation™ (nanosecond PFA or nsPFA™) energy"

Nanosecond pulsed field ablation is a medical technique that uses extremely short, high‑voltage electrical pulses—each lasting billionths of a second—to selectively disable small areas of tissue, most often to treat irregular heart rhythms. Like a precise, ultra‑brief electric zap that spares surrounding structures, it matters to investors because it can shorten procedure time, reduce complications and recovery, and therefore reshape demand, pricing and adoption for cardiac ablation devices and related services.

pulmonary vein isolation medical

"The durability of pulmonary vein isolation combined with the procedural efficiency"

Pulmonary vein isolation is a medical procedure that treats a common heart rhythm problem by using targeted energy to block abnormal electrical signals coming from the veins that return blood from the lungs to the heart. Think of it like disconnecting a shorted wire so the rest of the electrical system runs normally. Investors care because the procedure drives demand for specific medical devices, hospital services and follow-up care, and shifts potential revenue and regulatory risk in companies that make the tools and technologies used.

serious adverse event medical

"1.7% (3/177) of subjects experiencing a SAE related to the primary safety endpoint"

A serious adverse event is an unexpected medical problem tied to a treatment or trial that leads to death, is life‑threatening, requires (or prolongs) hospitalization, causes lasting disability, or results in a birth defect. Investors care because such events can prompt regulatory investigations, clinical holds, added safety studies, or product withdrawals—like a major car recall that halts sales, adds costs and damages trust, potentially affecting a company’s value and timelines.

feasibility study medical

"The ongoing feasibility study is assessing the initial safety and efficacy"

A feasibility study is an assessment that evaluates whether a proposed project or idea is practical and likely to succeed before investing significant time and resources. It considers factors like costs, potential benefits, and challenges, helping stakeholders decide if moving forward makes sense. Think of it as a detailed plan that gauges if a new venture is worth pursuing.

Understanding 8-K Material Events →

04/27/2026 - 09:18 AM

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): April 25, 2026

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 7.01

Regulation FD Disclosure.

On April 25, 2026, Pulse Biosciences, Inc. (the “Company”) issued a press release announcing additional key findings from the first-in-human clinical study of its nPulse Cardiac Catheter System to treat atrial fibrillation (the “study”). The findings were presented at Heart Rhythm 2026 in Chicago, Illinois, by Dr. Vivek Reddy, Director of Cardiac Arrhythmia Services at the Mount Sinai Fuster Heart Hospital. Key findings from the study include:

	●	Sustained 100% procedural success of evaluable patients by holter at 6 months (95/95);
	●	Sustained 96% procedural success of evaluable patients by holter at one year (51/53);
	●	Sustained 90% Kaplan-Meier estimate of freedom from AF/AFL/AT at one year;
	●	Consistently efficient procedural performance, including:
		Left atrial dwell time: 18.6 ± 13.0 minutes;
		Total procedure time: 60.2 ± 27.7 minutes;
		Fluoroscopy time: 9.4 ± 5.9 minutes;
		Average applications per-patient for PVI: 12.3 ± 2.6; and
	●	Safety profile across total cohort: maintained low serious adverse event rate, with 1.7% (3/177) of subjects experiencing a SAE related to the primary safety endpoint.

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.

On April 25, 2026, the Company also posted an updated investor presentation on its website (“Investor Deck”). This updated investor presentation discloses, among other things, some of the key findings from the study. The Company has used this updated Investor Deck and expects to continue to use it, either in whole or in part, and possibly with modifications, in connection with presentations to investors, analysts and others. A copy of the Investor Deck is attached hereto as Exhibit 99.2 and incorporated by reference in this Item 7.01. The Investor Deck is also available on the Company’s website at www.pulsebiosciences.com under “Investors.”

Except for the Investor Deck, information contained on, or accessible through, the Company’s website is not a part of, and is not incorporated by reference in, this Current Report on Form 8-K. The information contained in the Investor Deck itself is summary information only and it contains forward looking statements that are subject to risks and uncertainties, including those set forth in the Company’s filings with the U.S. Securities and Exchange Commission. Also, the information in the Investor Deck is as of April 2026, and the Company undertakes no obligation to publicly update or revise the information contained in the Investor Deck or this Item 7.01, except as required by law, although it made do so from time to time.

The information contained in Item 7.01 to this Current Report on Form 8-K and Exhibit 99.1 attached hereto 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 by the Company under the Securities Act of 1933, as amended, or the Exchange Act, unless expressly stated otherwise.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number	Description
99.1	Press Release issued by Pulse Biosciences, Inc. dated April 25, 2026 - Late-Breaking Updated Data from nPulse™ Cardiac Catheter System at Heart Rhythm 2026.
99.2	Investor Deck, dated April 25, 2026.
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: April 27, 2026	By:	/s/ Jon Skinner
		Jon Skinner
		Chief Financial Officer (Principal Financial Officer)

Exhibit 99.1

Pulse Biosciences Presents Positive Outcomes in Late-Breaking Updated Data from nPulse™ Cardiac Catheter System at Heart Rhythm 2026

Multicenter results show sustained high durability and procedural efficiency, redefining positive expectations for catheter ablation in patients with atrial fibrillation

HAYWARD, California, April 25, 2026 [Business Wire] – Pulse Biosciences, Inc. (Nasdaq: PLSE), developer of novel nPulse™ technology using proprietary Nanosecond Pulsed Field Ablation™ (nanosecond PFA or nsPFA™) energy, today announced late-breaking positive clinical data from its nPulse Cardiac Catheter System first-in-human feasibility study at the Heart Rhythm 2026 meeting.

The late-breaking presentation included incremental participant follow up data. Building upon the previously reported data set presented at the AF Symposium meeting in February of 2026, the expanded 6-month follow-up participant cohort increased to 95 subjects from 75 and the expanded 12-month follow-up participant cohort increased to 53 subjects from 47.

Key study findings on the 5 second ablation cohort include:

●

Sustained 100% procedural success of evaluable patients by holter at 6 months (95/95)

●

Sustained 96% procedural success of evaluable patients by holter at one year (51/53)

●

Sustained 90% Kaplan-Meier estimate of freedom from AF/AFL/AT at one year

●

Consistently efficient procedural performance, including:

Left atrial dwell time: 18.6 ± 13.0 minutes

Total procedure time: 60.2 ± 27.7 minutes

Fluoroscopy time: 9.4 ± 5.9 minutes

Average applications per-patient for PVI: 12.3 ± 2.6

●

Safety profile across total cohort: maintained low serious adverse event rate, with 1.7% (3/177) of subjects experiencing a SAE related to the primary safety endpoint

“These 12-month results are genuinely impressive,” said principal investigator Vivek Reddy, MD, Director of Cardiac Arrhythmia Services at the Mount Sinai Fuster Heart Hospital, NY. “The durability of pulmonary vein isolation combined with the procedural efficiency we’re seeing is not something we typically expect together at this stage of development. The consistency across patients and sites is particularly striking.”

The results from the study demonstrate durable pulmonary vein isolation and consistent procedural performance using a non-thermal nsPFA energy approach across multiple investigator sites was sustained with increased subject follow up. The data was presented by Dr. Vivek Reddy during a late-breaking clinical session on April 25, and included incremental follow-up results from the first-in-human feasibility study in patients with atrial fibrillation.

“Our Cardiac Catheter continues to demonstrate durable pulmonary vein isolation with highly consistent long-term outcomes and an efficient procedural workflow,” said David Kenigsberg, MD, FACC, FHRS, Chief Medical Officer of Pulse Biosciences. “The procedural efficiency we are seeing across 12 months of follow-up well exceeds my expectations, and reinforces the potential of nsPFA technology to meaningfully advance the field of atrial fibrillation ablation.”

The ongoing feasibility study is assessing the initial safety and efficacy of the nPulse Cardiac Catheter System for the treatment of AF (NCT06696170). To date, a total of 177 patients have been treated by 7 investigators in Europe, including the Na Homolce Hospital in Prague led by Dr. Vivek Reddy and Prof. Petr Neuzil, Jessa Hospital in Hasselt led by Dr. Johan Vijgen, and Tor Vergata Hospital in Rome, led by Dr. Andrea Natale. The initial cohort of treated patients has been evaluated by remapping at ~3 months and for rhythm control completed at 6 and 12 months post ablation procedure.

About Pulse Biosciences®

Pulse Biosciences is a novel bioelectric medicine company committed to health innovation that has the intention as well as potential to improve the quality of life for patients. The Company’s proprietary nPulse™ technology delivers nanosecond pulses of electrical energy to non-thermally clear cells while sparing adjacent noncellular tissue. The Company is actively pursuing the development of its nPulse technology for use in the treatment of atrial fibrillation and in a select few other markets where it could have a profound positive impact on healthcare for both patients and providers.

Pulse Biosciences, nPulse, Vybrance, CellFX, Nano-Pulse Stimulation, NPS, nsPFA, CellFX nsPFA and the stylized logos are among the trademarks and/or registered trademarks of Pulse Biosciences, Inc. in the United States and other countries.

Forward-Looking Statements

All statements in this press release that are not historical are forward-looking statements, including, among other things, statements concerning early clinical successes and whether they are predictive of the safety and effectiveness of any medical device such as the nPulse Cardiac Catheter System, Pulse Biosciences’ expectations, whether stated or implied, about whether the Company’s nsPFA technology will become either a disruptive treatment option or a superior option for treating atrial fibrillation or any other medical condition, statements relating to the effectiveness of the Company’s nsPFA technology and nPulse System to non-thermally clear cells while sparing adjacent non-cellular tissue, statements concerning the Company’s expected product development efforts, such as advancement of its nPulse Cardiac Catheter to treat paroxysmal atrial fibrillation, statements concerning whether any clinical study will show that the Company’s novel nsPFA mechanism of action and catheter design will deliver fast and precise ablations in cardiac tissue and streamline workflow, statements concerning market opportunities, customer adoption and future use of the nPulse System to address a range of conditions such as atrial fibrillation, and other future events. These statements are not historical facts but rather are based on Pulse Biosciences’ current expectations, estimates, and projections regarding Pulse Biosciences’ business, operations and other similar or related factors. Words such as “may,” “will,” “could,” “would,” “should,” “anticipate,” “predict,” “potential,” “continue,” “expects,” “intends,” “plans,” “projects,” “believes,” “estimates,” and other similar or related expressions are used to identify these forward-looking statements, although not all forward-looking statements contain these words. You should not place undue reliance on forward-looking statements because they involve known and unknown risks, uncertainties, and assumptions that are difficult or impossible to predict and, in some cases, beyond Pulse Biosciences’ control. Actual results may differ materially from those in the forward-looking statements as a result of a number of factors, including those described in Pulse Biosciences’ filings with the Securities and Exchange Commission. Pulse Biosciences undertakes no obligation to revise or update information in this release to reflect events or circumstances in the future, even if new information becomes available.

Contacts:

Media:

ICR Healthcare

Maggie Turano, Account Director

PulsebioPR@icrhealthcare.com

Investors:

Pulse Biosciences, Inc.

Jon Skinner, CFO

IR@pulsebiosciences.com

Gilmartin Group

Philip Trip Taylor

415.937.5406

philip@gilmartinir.com

Exhibit 99.2

Source: View Original Filing on SEC EDGAR

FAQ

What clinical results did Pulse Biosciences (PLSE) report for the nPulse Cardiac Catheter System?

Pulse Biosciences reported late-breaking data from its first-in-human feasibility study of the nPulse Cardiac Catheter System. The study showed 100% procedural success at six months in 95 evaluable patients and 96% procedural success at one year in 51 evaluable patients, with encouraging rhythm control durability.

How durable was atrial fibrillation control in Pulse Biosciences’ nPulse study?

Durability appeared strong, with a Kaplan-Meier estimate of 90% freedom from atrial fibrillation, atrial flutter, or atrial tachycardia at one year. These outcomes were reported from a multicenter first-in-human feasibility study using the company’s non-thermal nsPFA energy approach for pulmonary vein isolation in atrial fibrillation patients.

What safety outcomes were highlighted in the Pulse Biosciences (PLSE) nPulse trial update?

The safety profile showed a low rate of serious adverse events linked to the primary safety endpoint. Specifically, 1.7% of subjects, or 3 out of 177 treated patients, experienced such events. This rate was reported across the total cohort in the ongoing feasibility study of the nPulse Cardiac Catheter System.

How efficient were procedures in the nPulse atrial fibrillation feasibility study?

Procedural efficiency metrics were favorable. Average left atrial dwell time was 18.6 ± 13.0 minutes, total procedure time was 60.2 ± 27.7 minutes, and fluoroscopy time was 9.4 ± 5.9 minutes. Patients required an average of 12.3 ± 2.6 applications per patient for pulmonary vein isolation.

How many patients and centers were involved in the Pulse Biosciences nPulse study?

The feasibility study treated 177 patients across seven investigators in Europe. Sites included Na Homolce Hospital in Prague, Jessa Hospital in Hasselt, and Tor Vergata Hospital in Rome. Follow-up included remapping around three months and rhythm assessments at six and twelve months after ablation.

Where can investors find Pulse Biosciences’ detailed nPulse study data and presentation?

Investors can review a detailed press release (Exhibit 99.1) and an updated investor presentation (Exhibit 99.2) furnished with the company’s report. The investor deck, dated April 25, 2026, is also available on Pulse Biosciences’ website under the “Investors” section for further study information.

Filing Exhibits & Attachments

6 documents

New nPulse atrial fibrillation data for Pulse Biosciences (NASDAQ: PLSE)

Rhea-AI Filing Summary

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