Melinta Therapeutics, Inc. made a proposal to acquire Tetraphase Pharmaceuticals, Inc. (NasdaqGS:TTPH) for $27.3 million on May 14, 2020. Melinta Therapeutics, Inc. entered into definitive agreement to acquire Tetraphase Pharmaceuticals, Inc. for on June 4, 2020. Under the terms of agreement, Melinta Therapeutics agreed to pay Tetraphase $27 million in cash, plus an additional $12.5 million in cash potentially payable under contingent value rights to be issued in the transaction. Under the revised proposal, Melinta would acquire Tetraphase for approximately $27.0 million in cash, plus an additional $12.5 million in cash potentially payable upon the achievement of certain future XERAVA™ net sales milestones starting in 2021, payable under contingent value rights to be issued in the transaction. Under the revised proposal announced on May 21, 2020, the upfront cash consideration would be as follows: (i) $1.21 per share of Tetraphase common stock (including common stock underlying restricted stock units, performance-based stock units and pre-funded warrants), subject to downward adjustment in the event that the closing net cash of Tetraphase is less than $3 million, (ii) $1.75 per share of Tetraphase common stock underlying the common stock warrants issued by the Company in 2019, and (iii) $1.75 per share of Tetraphase common stock underlying the common stock warrants issued by it in 2020.

On May 27, 2020, Tetraphase received a further revised proposal from Melinta amending its May 21, 2020 proposal to acquire Tetraphase Pharmaceuticals, Inc. Under the amended proposal, Melinta would acquire Tetraphase for $34 million in cash, plus an additional $16 million in cash potentially payable under contingent value rights to be issued in the transaction. Under the amended proposal, the upfront cash consideration would be as follows: (i) $1.52 per share of Tetraphase common stock (including common stock underlying restricted stock units, performance-based stock units and pre-funded warrants), (ii) $2.21 per share of Tetraphase common stock underlying the common stock warrants issued by the Company in 2019, and (iii) $2.21 per share of Tetraphase common stock underlying the common stock warrants issued by the Company in 2020. In addition, the Amended Melinta Proposal does not provide for a downward adjustment based on the Company's closing net cash amount. On May 31, 2020, Tetraphase received a further revised proposal from Melinta amending its May 27, 2020 proposal. Under the amended proposal, Melinta would acquire Tetraphase for $39 million in cash, plus an additional $16 million in cash potentially payable under contingent value rights to be issued in the transaction. Under the amended proposal, the upfront cash consideration would be as follows: (i) $1.79 per share of Tetraphase common stock (including common stock underlying restricted stock units, performance-based stock units and pre-funded warrants), (ii) $2.47 per share of Tetraphase common stock underlying the common stock warrants issued by Tetraphase in 2019, and (iii) $2.47 per share of Tetraphase common stock underlying the common stock warrants issued by Tetraphase in 2020. In addition, the amended Melinta proposal does not provide for a downward adjustment based on the Tetraphase's closing net cash amount. Tetraphase equityholders would also be entitled to receive, for each share of Tetraphase common stock, one non-tradeable CVR, along with (i) $20 million during 2021, (ii) $35 million during any year ending on or before December 31, 2024 and (iii) $55 million during any year ending on or before December 31, 2024. Upon the closing of the transaction, Tetraphase will become a privately held company and will be continuing as the surviving corporation in the merger and shares of Tetraphase's common stock will no longer be listed on any public market. Under the terms of termination, Tetraphase will be required to pay the Melinta a termination fee of $1,150,000.

Closing of the transaction is subject to specified closing conditions, including that a majority of the Tetraphase's shares of common stock (treating the shares underlying the Company's RSUs and PRSUs as outstanding) are validly tendered and not validly withdrawn. On June 1, 2020, Tetraphase announced that its Board of Directors has determined that the amended Melinta proposal to acquire Tetraphase is a superior offer. The transaction was unanimously approved by the Board of Directors of Tetraphase and Melinta. As of June 12, 2020, tender offer has been commenced. On June 21, 2020, the Board of Tetraphase determined that the proposal from La Jolla Pharmaceutical Company to acquire Tetraphase is a “superior offer”. Tetraphase has given notice to Melinta of such determination and of its intention to consider changing its recommendation of the offer and the merger agreement from Melinta or terminating the Melinta merger agreement unless Melinta proposes revisions to the terms of the Melinta merger agreement or makes another proposal on or prior to June 26, 2020 that, if accepted, would result in the proposal from La Jolla Pharmaceutical ceasing to be a superior offer. The transaction is expected to close early in the third quarter of 2020.

Janney Montgomery Scott LLC acted as financial advisor and has rendered a fairness opinion to Tetraphase. Hal J. Leibowitz, Stuart Falber and Christopher D. Barnstable-Brown of Wilmer Cutler Pickering Hale and Dorr LLP acted as legal advisor to Tetraphase. Samuel Waxman and David Shine of Paul Hastings LLP acted as legal advisors to Melinta. D.F. King & Co., Inc. acted as the information agent and American Stock Transfer & Trust Company, LLC acted as the depositary and paying agent to Tetraphase in the offer.

Melinta Therapeutics, Inc. cancelled the acquisition of Tetraphase Pharmaceuticals, Inc. (NasdaqGS:TTPH) on June 24, 2020. The transaction was terminated due to entry into merger agreement with La Jolla Pharmaceutical Company, under which La Jolla Pharmaceutical will acquire Tetraphase Pharmaceuticals for an amount of $43 million in cash, plus an additional aggregate amount of $16 million in cash potentially payable under contingent value rights.