Cidara Therapeutics Acquisition Finalized by Merck, Shares Delisted

CIDARA THERAPEUTICS US1717572069

The acquisition of Cidara Therapeutics by pharmaceutical giant Merck & Co. has now been formally completed, rendering the company's shares no longer publicly tradable. This transaction concludes a multi-month process and transfers Cidara's key antiviral development pipeline to Merck. Shareholders are now set to receive the agreed-upon cash consideration.

The definitive merger agreement stipulated a cash tender offer of $221.50 per share of Cidara common stock. The total enterprise value of the deal is approximately $9.2 billion. Trading of Cidara shares on the Nasdaq exchange was suspended as of market open on January 8, 2026, following the last trading day on January 6, 2026.

Shareholder Process and Corporate Steps

For investors who held Cidara equity at the effective time of the merger, the $221.50 per-share payout will be distributed through the applicable paying agent process. Funds are expected to be deposited into respective brokerage accounts. Major institutional holders, including Bain Capital and Vanguard, have liquidated their positions at the acquisition price.

Concurrently, Cidara has requested the delisting of its shares from Nasdaq and has initiated the filing of a Form 25 with the U.S. Securities and Exchange Commission (SEC). The company is also preparing to terminate its SEC reporting obligations by filing a Form 15, which will suspend its duty to file periodic reports.

Strategic Rationale and Financial Context

The central asset driving this acquisition is Cidara's Cloudbreak platform and its lead candidate, CD388. This antiviral biologic, designed for both the prevention and treatment of seasonal and pandemic influenza, is currently in Phase 3 clinical development. Merck gains full access to the ANCHOR trial data, which recently achieved its target enrollment. Merck's management anticipates the CD388 program will significantly bolster its respiratory disease portfolio in 2026.

Financially, Cidara's equity experienced a substantial revaluation in the lead-up to the deal. Over the preceding 52-week period, the share price advanced from $15.22 to the final takeover bid of $221.50. This surge allowed institutional investors such as Vivo Capital and Adage Capital Partners to realize significant gains, particularly after increasing their stakes in 2025. In its final quarterly report prior to closure, Cidara reported a cash position of $476 million.

Following the announcement of the firm acquisition price, several research firms, including JPMorgan, RBC Capital Markets, and Morgan Stanley, adjusted their ratings on Cidara to the equivalent of "Neutral" or "Sector Perform."

The delisting marks a permanent end to Cidara's status as a publicly traded entity. With the disbursement of funds to shareholders and the cessation of public reporting, the company's operations and the promising CD388 program will now be integrated into Merck's broader research and development framework, shaping future advancements in respiratory medicine.