Another biotech startup is picking up where Pfizer left off with an experimental drug. Esanex wrapped up a $15.5 million round of financing last month and plans to advance an Hsp90 inhibitor that Pfizer ($PFE) acquired in the drug giant's 2008 buyout of Serenex.
As MedCity News reports, Esanex brings together members of the old Serenex team. Steve Hall, a partner at Eli Lilly's ($LLY) Lilly Ventures, co-founded Serenex and is now serving as chief executive of Esanex. In addition to Lilly Ventures, Esanex has drawn investments from the Indiana Seed Investment Fund II and Intersouth Partners, according to the report. Lilly Ventures also backed Serenex.
The investors are gambling on SNX-5422, which targets Hsp90 to inhibit tumor growth. Pfizer threw in the towel on the candidate after preclinical studies, MedCity reported. Some the drugs targeting the protein have run into trouble, including those from Infinity Pharmaceuticals ($INFI) and Bristol-Myers Squibb ($BMY). However, Hsp90 inhibition has shown promise in programs from Novartis ($NVS) and DebioPharm.
"The clinical development of Hsp90 inhibitors is an active and promising area in cancer research," Hall said in a release.
Pfizer has been shedding clinical-stage assets left and right in recent years as the company makes R&D cuts and reprioritizes its pipeline after big buyouts and loss of patents on key drugs such as Lipitor. Puma Biotechnology and Verastem ($VSTM) are two new companies with lead cancer contenders from Pfizer's pipeline.