May 2 (Reuters) - Novartis agreed to acquire

U.S. radiopharmaceutical company Mariana Oncology for $1 billion

upfront, boosting its portfolio of precision cancer treatments

in development, the Swiss drug manufacturer said on Thursday.

The deal includes up to $750 million of further payments

upon achieving certain milestones, it added.

Mariana Oncology is working on novel radioligand cancer

therapies (RLTs) that have not yet been tested on humans.

"The transaction bolsters the Novartis RLT pipeline and

expands the company's research infrastructure and clinical

supply capabilities," Novartis said in a statement.

Radioligand therapy, based on cell-killing radioactive

particles that are attached to tumour-seeking molecules, is one

of three technologies that Novartis' development efforts are

focused on, apart from cell and gene therapy as well as RNA.

The Swiss group's radioligand drugs include Pluvicto against

prostate cancer and Lutathera against a rare group of

gastrointestinal tumours.

Novartis has been cutting jobs and costs, and spun off its

generic drugs business Sandoz last year, part of a focus on

fewer therapeutic areas and geographic markets.

In February, it struck a deal to buy German cancer drug

developer MorphoSys for 2.7 billion euros ($2.89

billion).

($1 = 0.9348 euros)

(Additional reporting by Paul Arnold,

editing by Matthias Williams and Elaine Hardcastle)