Savitz Ryan 4

What Happened
Ryan Savitz, EVP, CFO & CBO of Dianthus Therapeutics (DNTH), exercised 8,224 stock options (strike $17.88) on April 9, 2026 to acquire 8,224 shares and immediately sold those 8,224 shares in the open market. The exercise cost was $147,045 (8,224 × $17.88); the shares were sold at a weighted-average price of $89.84 for aggregate proceeds of about $738,844. The underlying option position was terminated upon exercise.

Key Details

• Transaction date: April 9, 2026. Form filed April 10, 2026 (timely).
• Exercise: 8,224 shares acquired at $17.88 per share = $147,045.
• Sale: 8,224 shares sold at weighted-average $89.84 per share = ~$738,844 (sales ranged $89.75–$89.95).
• Derivative disposition: 8,224 option shares shown as disposed at $0, reflecting cancellation of the option upon exercise.
• Trading plan: Sales were made under a Rule 10b5-1 plan adopted December 30, 2025.
• Vesting note: The option award vests in equal monthly installments over four years from January 1, 2024, subject to continued service.
• Shares owned after the transaction: Not disclosed in this Form 4.

Context
This was an exercise-and-sell (effectively a cashless exercise) executed and sold the same day under a pre-arranged 10b5-1 plan, which is commonly used by insiders to systematically sell shares and reduces the implication of opportunistic timing. The filing is factual and does not indicate insider intent beyond following the plan.