Merck Finalizes Cidara Therapeutics Acquisition

Key highlights
  • Merck completed the cash offer at $221.50 per Cidara share.
  • 27,149,333 shares were tendered, representing 85.96% of Cidara's total shares.
  • The acquisition will increase 2026 R&D expenses by $9.0 billion.
  • CD388 is a long-acting antiviral for influenza prevention.

Acquisition Details

Merck has completed the acquisition of Cidara Therapeutics through a cash tender offer, purchasing all outstanding shares at $221.50 each. As of the offer's expiration, 27,149,333 shares were tendered, representing approximately 85.96% of Cidara's total shares.

Financial Impact

The acquisition is expected to be accounted for as an asset acquisition, increasing Merck's 2026 research and development expenses by approximately $9.0 billion. Additionally, GAAP and non-GAAP EPS are projected to be negatively impacted by about $0.30 per share in the first 12 months due to costs associated with advancing CD388 and financing.

CD388 Overview

CD388 is an investigational drug-Fc conjugate designed to prevent influenza infection in individuals at higher risk of complications. It is a long-acting small molecule inhibitor with broad antiviral activity against influenza A and B viruses, including certain pandemic strains. CD388 is currently being evaluated in the Phase 3 ANCHOR study among high-risk adult and adolescent participants.

Source: Merck

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