PULSE BIOSCIENCES, INC.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM8-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 7, 2026

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):

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Securities registered pursuant to Section 12(b) of the Act:

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. ☐

On April 7, 2026, Pulse Biosciences, Inc. (the “Company”) issued a press release announcing the first enrollment of patients in its NANOPULSE-AF clinical study, a prospective, multicenter, pivotal, clinical investigation currently evaluating the Company’s nPulse™ Cardiac Catheter System for treating recurrent, drug-resistant, symptomatic paroxysmal atrial fibrillation (the “Study”). The first seven patients in the Study were treated at St. Bernards Medical Center in Jonesboro, Arkansas, by Devi Nair, MD, Principal Investigator of the Arrhythmia Research Group. The Company plans to enroll approximately 215 participants in the Study, across multiple clinical sites, and expects the primary endpoints will be assessed at 6 and 12 months post-ablation to measure procedural success and safety outcomes.

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.

(d) Exhibits

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.