Company: NCEL
Filing Date: 2025-10-28
Form Type: 6-K
Source: 0001213900-25-103130
Chunk: 0

Company: NewcelX Ltd.
Filing Date: 2025-10-28
Form: 6-K
Chunk 0
---
<div align='center'>UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the Month of October 2025 (Report No. 5)

Commission File Number: 001-39957

NLS PHARMACEUTICS LTD.

(Translation of registrant’s name into English)

The Circle 6

8058 Zurich, Switzerland

(Address of principal executive office)</div>

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

<div align='center'>☒ Form 20-F ☐ Form 40-F</div>

<div align='center'>CONTENTS</div>

On October 28, 2025, NLS Pharmaceutics Ltd. issued a press release
titled: “NLS Pharmaceutics and Kadimastem Announce Completion of Material Conditions Precedent for Merger Transaction and Delisting
Date of Kadimastem’s Shares.” A copy of this press release is furnished herewith as Exhibit 99.1.

<div align='center'>EXHIBIT INDEX</div>

| Exhibit 
 Number  |     | Description                                                                                                                                                                    
 of Document                                                                                                                                                                    |
| 99.1    |     | Press release titled: “NLS Pharmaceutics and Kadimastem Announce Completion of Material Conditions Precedent for Merger Transaction and Delisting Date of Kadimastem’s Shares” |

| 1 |

<div align='center'>SIGNATURES</div>

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.

| Date: October 28, 2025 | NLS Pharmaceutics Ltd. 
 By:                    | /s/                
 Alexander C. Zwyer |                         |
|:-----------------------|:-----------------------|:-------------------|:------------------------|
|                        |                        | Name:              | Alexander C. Zwyer      |
|                        |                        | Title:             | Chief Executive Officer |

| 2 |