Swiss drugmaker Novartis has agreed to acquire Mariana Oncology, a US-based biotechnology company focused on novel radioligand therapies (RLTs) to treat cancers, for $1.75bn.

Under the terms of the agreement, Novartis will make an upfront payment of $1bn and additional payments of $750m contingent on the completion of pre-specified milestones.

The acquisition includes Mariana’s portfolio of RLT programs spanning lead optimisation to early development across breast, prostate, and lung cancers.

It also includes the biotechnology company’s development candidate MC-339, an actinium-based RLT being investigated in small-cell lung cancer.

Novartis said the proposed acquisition will strengthen its RLT pipeline and expand its research infrastructure and clinical supply capabilities.

Novartis biomedical research president Fiona Marshall said: “The acquisition of Mariana Oncology reflects our commitment to radioligand therapy as one of our company’s key technology platforms and strengthens our leadership in this field.

“We are excited to work with the Mariana team to bring forward next-generation RLTs for patients living with cancer and together shape the future of RLT as a pillar for oncology treatment.”

RLTs comprise a tumour-targeting molecule (ligand) with a therapeutic radioisotope, and they bind to specific receptors expressed on the surface of certain types of tumours.

Upon binding to a target cell, emissions from the therapeutic radioisotope cause DNA damage that can inhibit cell growth and replication and potentially trigger cell death.

The targeted approach enables the RLTs to deliver the radiation to the tumour while preventing damage to the surrounding cells.

Currently, Novartis has two approved RLTs for patients with metastatic castration-resistant prostate cancer and certain gastro-entero-pancreatic neuroendocrine tumours.

Its early and late-stage pipeline comprises several programs, including several studies and assets for prostate cancer and other preclinical and discovery programs.

Novartis oncology biomedical research global head Shiva Malek said: “As pioneers in radioligand therapies, we are dedicated to building on our scientific leadership and expanding the breadth of these potentially transformative treatments to a broader range of cancer types.

“This acquisition brings to Novartis phenomenal talent and new capabilities in RLT research that complement our wide-ranging internal efforts to explore novel isotopes, combinations, disease areas, and more.”