Eidos Therapeutics raises $106M IPO to advance ATTR med

Rare disease biotech Eidos Therapeutics priced its IPO at $17 a share, hauling in about $106.3 million to push its treatment for transthyretin (TTR) amyloidosis through the clinic. The offering comes on the heels of a $64 million series B round, completed in April. 

ATTR is caused by a mutation in the TTR gene, resulting in abnormal TTR proteins that fold incorrectly and build up in the body's organs and tissues. Symptoms depend on which part of the body the protein accumulates and usually include neuropathy as well as cardiomyopathy. Eidos is working on a small molecule, AG-10, which is designed to treat ATTR by binding to and stabilizing these proteins. It is in development for TTR cardiomyopathy and TTR polyneuropathy. 

"Our clinical data demonstrate that AG10 has a safe, well-tolerated profile and is able to stabilize 100% of plasma TTR at peak concentrations and provide average levels of stabilization greater than 95% at steady-state," said Eidos CEO Neil Kumar, Ph.D., at the series B close. "Given that increasing levels of stabilization have yielded progressively better clinical results in past trials, our near-complete levels of stabilization suggest that AG10 could be a best-in-class solution. We are targeting ATTR at its source by stabilizing TTR, an approach that is validated by genetics and clinical data." 

The series B cash set Eidos up to move AG-10 into phase 2, as well as continue its phase 3 preparations. As for its IPO cash, the biotech expects it to last at least a year.  

"Approximately 80% of the net proceeds will be used to fund our clinical development of AG10 for the treatment of ATTR-CM and ATTR-PN, including our ongoing Phase 2 ATTR-CM and planned Phase 3 ATTR-PN clinical trials, as well as future clinical trials and additional research and development activities," Eidos said in its prospectus. 

Eidos expects to complete its phase 2 and phase 3 trials, but the IPO haul will not be enough to see AG-10 through regulatory approval and the company will have to raise additional capital. 

The Bay Area-based Eidos is chasing Alnylam and Ionis, the frontrunners in the TTR space. Alnylam is expecting FDA approval for patisiran by Aug. 11, while Ionis and commercialization partner Akcea faced a setback in May after the agency pushed back the action date for inotersen. Pfizer is working on a treatment for TTR cardiomyopathy, recently sharing topline phase 3 data showing tafamidis bested placebo in all-cause mortality and frequency of cardiovascular-related hospitalizations after 30 months of treatment.