Startup radiopharmaceutical developer Mariana Oncology raises $175M in series B financing

Mariana Oncology has raised $175 million in new capital, the Cambridge, Massachusetts-based radiopharmaceutical developer announced Sept. 7.

Investment firms Deep Track Capital and Forbion co-led the series B financing round, with other contributors including Surveyor Capital (a Citadel company) and pharma giant Eli Lilly and Co. Mariana Oncology will use the money to continue developing its portfolio of radiopharmaceuticals including “lead candidate” MC-339, a peptidic small molecule targeted for the treatment of small cell lung cancer.  

“These therapies are transforming care for select cancers and are primed to do so across a broader set of indications,” Rebecca Luse of Deep Track Capital, who is joining the company’s board alongside a representative from Forbion, said in an announcement. “Mariana Oncology’s pipeline is innovative and differentiated from most existing radiopharmaceutical companies. We are compelled by the broader opportunity for radiopharmaceuticals beyond prostate cancer and look forward to supporting Mariana Oncology’s success along with their seasoned leadership team and strong syndicate.”

Founding investors in the company include Atlas Venture, Access Biotechnology and RA Capital Management, with Nextech Invest among the new contributors.

Simon Read, PhD—the former chief scientific officer of Ra Pharma and entrepreneur in residence at Atlas Ventures—founded Mariana Oncology after the latter incubated the startup for 18 months. He and colleagues completed their series A financing round in 2021, exiting stealth mode after raising an initial $75 million. The company previously went by the name Curie Therapeutics but shifted to the new title to better reflect its mission.

“The support of such a strong syndicate of new and existing investors is a testament to Mariana Oncology’s potential,” Read said in the announcement, adding that he expects MC-339 to enter the clinic by next year.