Vanda Pharmaceuticals Inc.

During the fiscal quarter ended March 31, 2026, none of our directors or officers informed us of the adoption, modification or termination of a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408. Furthermore, during the fiscal quarter ended March 31, 2026, we did notadopt orterminate a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408.

On April 22, 2026, our board of directors approved, subject to stockholder approval, an amendment to our Amended and Restated 2016 Equity Incentive Plan, as amended (the 2016 Plan). The amendment to the 2016 Plan, if approved by the stockholders, will increase the aggregate number of shares of common stock that may be issued by us pursuant to awards under the 2016 Plan by 2,500,000 shares.

The information below included in this Item 5 is provided in lieu of filing such information on a Current Report on Form 8-K under Item 1.01.

Item 1.01. Entry into a Material Definitive Agreement.

On May 1, 2026, the Company entered into Amendment No. 8 to its lease for its headquarters in Washington, D.C with its landlord, Square 54 Office Owner LLC. The amendment (i) expands the leased premises, (ii) confirms the early termination of certain space effective November 30, 2026 and (iii) extends the lease term for the remaining and additional space through July 31, 2038. The amendment also provides for base rent, rent abatements, tenant improvement allowances and related customary terms.

The foregoing description is qualified in its entirety by reference to Amendment No. 8, which will be filed as an exhibit to the Company’s Quarterly Report on Form 10-Q for the quarter ending June 30, 2026.