Cidara regains rights to flu med after Janssen makes good on promise to divest

Cidara Therapeutics already knew Janssen planned to hand off its obligations to their flu prophylaxis candidate to another entity. Now it turns out that entity will be … Cidara.

Janssen licensed the antiviral CD388 from Cidara back in April 2021, but the Johnson & Johnson unit has since made no secret of its intentions to discontinue internal development amid a larger winding down of all infectious disease and vaccine R&D outlined last year.

In September 2023, Cidara said Janssen had elected to proceed with CD388, triggering a $7 million milestone payment but the smaller biotech also reaffirmed that Janssen didn’t intend to develop the asset but rather “transfer its rights and obligations under the agreement to another entity.”

This afternoon, Cidara revealed that Janssen’s rights will be coming home. Cidara will now once again have the exclusive global development and commercial rights to CD388, the company explained in a post-market release April 24. But the biotech had to cough up a $85 million upfront payment to Janssen, with potential development, regulatory, and commercial milestone payments to follow.

Having entered the year with $35.8 million in cash and equivalents, losing a Big Pharma partner means Cidara has a funding hole to fill if it still wants to launch a planned phase 2b trial of CD388 during the next Northern Hemisphere influenza season. To this end, the biotech announced in the same release that it has secured $240 million from a private placement of stock led by RA Capital Management.

“This reacquisition of CD388, along with the capital to advance it through phase 2b development, is transformational for Cidara and especially for those who could benefit from a long-acting, universal preventative against all forms of influenza,” Cidara’s CEO Jeffrey Stein, Ph.D., said in the release.

“In our phase 2b study later this year, we will evaluate the efficacy and safety of CD388 in providing season-long, universal protection from influenza,” Stein added. “We believe that CD388 may have significant advantages beyond and in addition to flu vaccines, with the potential for universal protection even in the absence of a robust immune response and without the requirement for seasonal influenza strain prediction.”

This is not the only pipeline shake-up at Cidara. On the same day, the company announced the divestment of approved invasive candidiasis treatment Rezzayo to Mundipharma, which already owns the rights to the antiviral outside of the U.S. and Japan.

With a phase 3 trial of the FDA-approved drug due to be expanded, Cidara said cutting Rezzayo loose would save around $67 million in clinical development expenses as well as another $61 million in “forecasted obligations.” It would also help Cidara focus on its drug-Fc conjugate program, including a planned investigational new drug filing for its lead oncology candidate, a CD73 inhibitor called CBO421.

“We expect that the capital infusion from [the private placement], together with existing cash and the expected near-term cost savings associated with our recently announced divestiture of rezafungin to Mundipharma, positions us well to execute on the CD388 development program and advance the key assets in our pipeline,” Stein explained.