Cidara gains first FDA approval, $20M milestone payment as FDA endorses Rezzayo

Last month, Cidara Therapeutics regained compliance with Nasdaq after a year in which its share price dipped below $1. Over time, trial failures had reduced investors’ confidence in the San Diego biotech, once a Fierce 15 company whose shares eventually reached a price of more than $17.

But now, after garnering its first FDA approval in its 11-year history, Cidara finally appears to have reversed its downturn.

On Wednesday, the FDA signed off on Rezzayo (rezafungin for injection), a once-weekly antifungal to treat invasive candidiasis and candidemia, which are bloodstream infections in hospitalized patients that can be fatal.

Rezzayo is a next-generation echinocandin and the first new treatment option in the indication in more than a decade. Unlike typical yeast infections, candidiasis can affect the blood, eyes, heart, brain and bones, according to the CDC.

With the approval, Cidara receives a $20 million milestone payment from Melinta Therapeutics, which paid $30 million last year for licensing rights to the drug in the United States. In total, Cidara could make $460 million on the deal, including $370 in commercial milestones plus tiered royalties tied to annual sales.

Melinta is a 23-year-old Connecticut biotech with five approved antibiotics and antibacterials including high blood pressure med Toprol-XL, which it acquired from AstraZeneca.

RELATED: Cidara fails phase 2 study, drops med in vulvovaginal candidiasis

In a release, Melinta CEO Christine Miller said the company expects to bring Rezzayo to the market “this summer.”

Mundipharma has the rights to market Rezzayo outside of the U.S. The company made a $11 million milestone payment to Cidara in October of last year when the European Medicines Agency accepted the marketing application for Rezzayo.  

The FDA endorsement comes after Rezzayo gained FDA orphan drug and qualified infectious disease product (QIDP) designations. Two months ago, the FDA’s Antimicrobial Drugs Advisory Committee voted 14-1 to recommend it for approval.

Rezzayo passed muster in the phase 2 Strive and phase 3 Restore trials where both showed statistical non-inferiority to standard of care treatment caspofungin. Known commercially as Cancidas and sold by Merck, the drug was approved in 2001 and now is available in generic forms.

RELATED: Cidara Therapeutics bags $30M cash in Melinta licensing deal, submits antifungal for FDA review

Cidara now moves on to advancing its Cloudbreak drug-Fc conjugate platform programs. The company also is investigating Rezzayo as a treatment to prevent invasive fungal disease in patients undergoing allogeneic blood and marrow transplantation.