SCHEDULE: Merck Subsidiary to Acquire Cidara Therapeutics

Merck Sharp & Dohme LLC's subsidiary, Caymus Purchaser, Inc., will launch a cash tender offer to acquire Cidara Therapeutics, Inc. for $221.50 per common share and $15,505.00 per Series A preferred share.

Summary

• Cidara Therapeutics, Inc. has entered into a Merger Agreement with Merck Sharp & Dohme LLC (Parent) and Caymus Purchaser, Inc. (Purchaser), a wholly-owned subsidiary of Parent, on November 13, 2025.
• Purchaser will commence a cash tender offer no later than December 4, 2025, to acquire all outstanding common shares at $221.50 per share and all outstanding Series A preferred shares at $15,505.00 per share.
• The tender offer is contingent on a majority of outstanding shares being validly tendered and not withdrawn, and the expiration or termination of the Hart-Scott-Rodino Antitrust waiting period.
• Following the tender offer, Purchaser will merge with Cidara Therapeutics, Inc., with Cidara surviving as a wholly-owned subsidiary of Parent.
• Outstanding stock options will accelerate, become fully vested, and be converted into a cash payment based on the difference between the Common Share Merger Consideration and the exercise price.
• Warrants, including Pre-Funded Warrants, will be treated as simultaneously cashless exercised immediately prior to the merger's effective time.
• Upon closing of the merger, Cidara's common stock will be deregistered and delisted from the Nasdaq Stock Market.
• RA Capital Healthcare Fund, L.P., a significant shareholder, has entered into a Tender and Support Agreement, agreeing to tender its shares, vote in favor of the merger, and not transfer its shares, subject to certain exceptions.
• RA Capital Management, L.P., Peter Kolchinsky, Rajeev Shah, and RA Capital Healthcare Fund, L.P. collectively beneficially own 3,372,923 shares, representing 10.7% of the common stock outstanding as of November 3, 2025.

Sentiment

Score: 8

Explanation: The sentiment is highly positive for existing shareholders due to a definitive cash acquisition at a specified price, providing a clear and certain return. The transaction is well-defined with a support agreement from a major investor. The only minor detraction is the loss of independent company status, which is inherent in an acquisition.

Positives

• Definitive acquisition provides a clear exit strategy and liquidity for shareholders at a fixed cash price.
• Common shareholders will receive $221.50 per share in cash.
• Series A preferred shareholders will receive $15,505.00 per share in cash.
• Stock options will accelerate and vest, converting into cash payments for in-the-money options.

Negatives

• Cidara Therapeutics, Inc. will cease to be an independent publicly traded company.
• Common stock will be delisted from Nasdaq and deregistered, removing future investment opportunities in the standalone entity.

Risks

• The tender offer is subject to conditions, including a minimum tender of shares (one more than 50% of outstanding shares) and Hart-Scott-Rodino Antitrust Improvements Act clearance.
• Shareholders who do not tender their shares may exercise statutory appraisal rights under Delaware law, which could result in a different valuation.
• Any option with an exercise price equal to or exceeding the Common Share Merger Consideration will be cancelled for no consideration.

Future Outlook

Cidara Therapeutics, Inc. will become a wholly-owned subsidiary of Merck Sharp & Dohme LLC, and its common stock will be delisted from the Nasdaq Stock Market, ceasing to be an independent public entity.

Industry Context

This acquisition reflects a continuing trend in the biotechnology and pharmaceutical sectors where larger, established pharmaceutical companies acquire smaller, innovative biotech firms to expand their pipelines and technology portfolios. Merck's move to acquire Cidara suggests strategic interest in Cidara's assets or capabilities.

Corporate Governance

Related Party Transactions

• RA Capital Healthcare Fund, L.P., a significant shareholder (10.7% beneficial ownership), entered into a Tender and Support Agreement with Parent and Purchaser in connection with the merger.

Stakeholder Impact

• Shareholders: Will receive cash for their shares, providing liquidity and a defined return. Those not tendering may pursue appraisal rights.
• Employees: Implied changes to employment structure and corporate culture as Cidara integrates into Merck's operations.
• Company: Cidara Therapeutics, Inc. will cease to exist as an independent public entity, becoming a subsidiary of Merck.

Next Steps

• Purchaser to commence a cash tender offer no later than December 4, 2025.
• Satisfaction or waiver of tender offer conditions, including the minimum tender threshold and Hart-Scott-Rodino Antitrust clearance.
• Consummation of the merger, with Cidara Therapeutics, Inc. becoming a wholly-owned subsidiary of Merck Sharp & Dohme LLC.
• Deregistration of Cidara's common stock under the Securities and Exchange Act of 1934 and delisting from the Nasdaq Stock Market.

Key Dates

Recommendation

For existing shareholders, the recommendation is to hold shares and tender them into the offer, as the acquisition price is fixed and the transaction appears highly likely to close given the definitive agreement and shareholder support. Selling on the open market before the tender offer would only be advisable if the market price is very close to the offer price and immediate liquidity is preferred, otherwise, holding for the tender is the most straightforward path to realize the offer price. For new investors, there is little to no upside given the fixed cash offer and imminent delisting, making a 'buy' recommendation inappropriate.

Keywords

Cidara Therapeutics, Merck, Acquisition, Tender Offer, Merger Agreement, Biotechnology, Pharmaceuticals, M&A, Schedule 13D, RA Capital