
A Novartis castoff drug gets new life at an Atlas-backed startup looking to blaze a trail in obesity
After decades of failure, the obesity field is finally seeing some major progress with the success of a stable of GLP-1 diabetes drugs showing clinical benefit. A small biotech thinks it has something new to offer in that space with an older drug, and investors like what they see so far.
Versanis Bio launched Tuesday with a $70 million A round backed by biotech blue-chippers Atlas Venture and Medicxi with lead candidate bimagrumab, an in-licensed Novartis drug originally targeting muscle weakness, gearing up for a Phase II study in obesity.
It’s early days for Versanis, a startup out of Marc Fishman and Joe Jimenez’s incubator Aditum Bio, but not for bimagrumab, an activin type 2 receptor inhibitor which has data from thousands of patients already published and a potential leg up over GLP-1 diabetes drugs like semaglutide and tirzepatide due to its cleaner safety profile, CEO Lloyd Klickstein told Endpoints News.
In Phase II data published back in January when the drug was still under Novartis’ control, bimagrumab significantly cut body fat mass and improved lean mass compared with placebo after 48 weeks in patients with type 2 diabetes, potentially cracking open a path forward in obesity. Bimagrumab’s big upside, in Klickstein’s telling, is its ability to cut fat without cutting lean muscle, an efficacy profile more in line with improving clinical outcomes and lowering risk factors than other drugs that target weight alone.
“This antibody is very much de-risked in terms of its efficacy,” Klickstein said. “We know it works. Really, we have an operational challenge more so than a scientific challenge for this drug.”
Now, Versanis will take its new treasure chest and aim for a “comprehensive” Phase II study to pivot bimagrumab specifically into obesity. The going won’t be easy on that: Versanis is working to re-manufacture the drug for the mid-stage test as well as expand the potential patient population beyond just diabetes while also working on developing a more user-friendly subcutaneous application.
That’s plenty of work left to figure out, and Versanis as of now is staying mum on when the trial is expected to begin or when we can expect data.
But bimagrumab’s existing data and the strength of Versanis’ leadership team were enough to bring on two major investors in Atlas and Medicxi, both of which value startups with a clear lead product in an emerging therapeutic area.

Klickstein hails from NIBR, where he worked alongside Fishman, the founding director at NIBR, and Jimenez, a former Novartis CEO, who co-founded Aditum. This is the first go at CEO for Klickstein, but he highlighted his work as head of translation at NIBR’s early discovery units — an experience compared with a “biotech inside a pharma.”
And he’s got a nice rolodex anyway of CEO friends and mentors to lean on with Fishman and Jimenez jumping onto the Versanis board.
Michael Gladstone, an Atlas general partner who will also join the Versanis board, highlighted the biotech’s strong data and bimagrumab’s market potential in obesity, where severe GI side effects are common, as a clear-cut case for investment.
“To start a company standing on the shoulders of that kind of data set and understanding the mechanisms to address an area of immense, virtually unquantifiable unmet need is really exciting,” he said.