VenatoRx raises $42M to take drug for breaking bacterial resistance to approval

VenatoRx Pharmaceuticals has raised $42 million to fund antibiotic R&D. The series B equips the biotech to take its lead treatment for multidrug-resistant Gram‐negative infections through clinical trials and up to a filing for approval with the FDA.

Versant Ventures led the round with the support of Abingworth and Foresite Capital. Securing the backing of the well-known institutional investors marks a shift in strategy for VenatoRx, which has progressed over the past seven years using a mix of government grants and an angel-backed $3.5 million series A round. That approach has brought VenatoRx to the point that it needs more money to push deep into the clinic—and has the data to attract such levels of financing.

VNRX‐5133 is the trigger for the shift in strategy. VenatoRx tested the intravenous beta‐lactamase inhibitor in an 84-person study earlier this year, giving it safety data in healthy volunteers to back up its preclinical evidence of efficacy. VenatoRx plans to use the drug to inhibit bacterial resistance mechanisms, enabling a paired beta-lactam antibiotic to kill the microorganisms.

The combination of the data and money means the company is now positioned to advance into registrational studies in the first half of next year. That will give VenatoRx a look at the efficacy of VNRX‐5133—including in patients with established resistant pathogens—and set it up to file for FDA approval if successful.

“This $42 million financing is part of an overall financial strategy that will take 5133 all the way to registration,” VenatoRx CEO Christopher Burns, Ph.D., said. 

Expectations that VNRX‐5133 can help hard-to-treat patients are underpinned by evidence that it inhibits the enzymes bacteria produce to fight off beta‐lactam antibiotics. 

Significantly, VNRX‐5133 is designed to inhibit the four major classes of beta‐lactamase resistance enzymes, including metallo‐beta‐lactamases (MBL). AstraZeneca and Allergan won FDA approval in 2015 for a drug featuring a novel beta‐lactamase inhibitor—Avycaz—but research suggests it struggles against MBL. 

If VNRX‐5133 can facilitate the killing of a broader spectrum of Gram-negative bacteria, including Pseudomonas aeruginosa strains, it could become a valuable weapon in the arms race against microorganisms. 

The potential for VenatoRx to turn such a weapon into a return on investment attracted the VCs. Burns and fellow cofounders Luigi Xerri, Ph.D., and Daniel Pevear, Ph.D., have a track record in this area. 

Xerri also cofounded Protez Pharmaceuticals. Burns and Pevear went on to join the company, and together they helped it land a $400 million buyout bid from Novartis. The story ended with Novartis closing Protez’s operation and dropping its broad-spectrum antibiotic after safety data raised a red flag. But Burns, Xerri and Pevear emerged to found VenatoRx.  

The rest of VenatoRx’s pipeline is led by VNRX‐7145, an orally bioavailable beta‐lactamase inhibitor that is in late preclinical testing. VenatoRx will use some of the $42 million to push VNRX‐7145 forward while also working on earlier-stage programs designed to bypass bacterial resistance mechanisms by targeting penicillin-binding proteins.