Cancer-focused Boundless Bio to go public as 2024 IPO rally continues


Cancer-focused Boundless Bio to go public as 2024 IPO rally continues

Published: Mar 07, 2024

By Tristan Manalac


Boundless Bio on Wednesday launched its bid to go public, seeking additional funds to develop novel therapies targeting extrachromosomal DNA for various cancer indications.

The Bayer- and RA Capital-backed biotech has yet to disclose how much it expects to make from its initial public offering (IPO), nor has it given a specific timeline for going public, only that it expects to close the offering within the year. Once closed, Boundless proposes to trade on the Nasdaq Global Market under the ticker symbol BOLD.

Boundless is planning to use its IPO proceeds to support the development of its three therapeutic candidates that target extrachromosomal DNA (ecDNA), which play a central role in the amplification of cancer-causing genes in approximately 14% of malignancies, according to the company’s SEC filing on Wednesday.

With its proprietary Spyglass platform, Boundless is now working on three cancer programs that work by blocking specific ecDNA targets, stopping them from amplifying oncogenes and preventing tumor cells from adapting and building resistance to existing therapies. The biotech’s candidates specifically target cancer cells with ecDNA without affecting healthy cells.

Two of its programs are currently in Phase I studies. Its lead program, dubbed BBI-355, is a selective blocker of checkpoint kinase 1, which is key to the replication and transcription of ecDNA in cancer cells. BBI-355 is being evaluated in the Phase I/II POTENTIATE study, with early data expected in the second half of 2024.

Boundless’ second program is BBI-825, an oral inhibitor of ribonucleotide reductase, which helps assemble and repair ecDNA in cancer cells. The biotech is running the Phase I/II STARMAP trial and expects early proof-of-concept data in the latter half of 2025.

The biotech’s third ecDNA candidate is still in the discovery phase. Boundless is planning to submit an Investigational New Drug application for this program as early as the first half of 2026, according to its SEC filing.

In addition to supporting its clinical pipeline, Boundless will also use the IPO’s proceeds to fund the development of an ecDNA diagnostic test—preliminarily dubbed ECHO—which will use genomic data from routine screening assays to detect ecDNA in patients’ tumor samples.

Boundless’ IPO will add to the more than $252 million that the biotech has raised since its inception. This sum includes an oversubscribed $105 million Series B round in April 2021, which was backed primarily by RA Capital Management and Nextech Invest. Boundless closed another fundraising round in May 2023, securing $100 million in an oversubscribed Series C led by RA and Bayer.

Wednesday’s IPO filing also continues the industry’s rally in 2024, which was started by CG Oncology in January and includes ArriVent BiopharmaKyverna Therapeutics and pre-clinical biotech Metagenomi, as well as Alto Neuroscience and Fractyl Health.

Source: BioSpace