Baxter International has bagged the European rights to fellow USA-based Onconova Therapeutics' investigational cancer drug rigosertib.

The latter is currently in Phase III for the treatment of a group of rare haematologic malignancies called myelodysplastic syndromes (MDS) and in a Phase II/III study for pancreatic cancer. Under the terms of the agreement, Baxter will pay $50 million upfront, while Onconova may receive up to $515 million in development and regulatory payments, plus sales milestones and royalties.

Baxter, which has previously invested $50 million in Onconova,  also has the option to develop rigosertib in additional indications. Its current oncology portfolio includes chemotherapeutic agents used alone or in combination to treat cancers such as non-Hodgkin’s lymphoma, as well as anti-emetic products designed to relieve side effects of cancer drugs.

Rigosertib targets dual pathways (PI-3K and PLK) critical to the growth of cancer cells and has been studied in more than 600 patients. It has orphan drug designation for MDS in the USA and Europe; the annual incidence of MDS in the latter is approximately three per 100,000 people.

Ludwig Hantson, head of Baxter’s bioscience business, said that rigosertib’s first anticipated indication would be a natural complement to the firm's existing treatments for patients managing rare haematologic conditions "and will allow us to expand the product portfolio of our existing haematologic sales force".

Ramesh Kumar, Onconova chief executive, said "the financial resources resulting from this transaction will help to advance the rigosertib programme toward commercialisation and will support other Onconova candidates in clinical development". These include Ex-RAD, a radioprotectant, and ON 013105, another anti-cancer agent.