The deal is structured in three parts, with Celgene paying $1.1bn in cash upfront for Impact Biomedicines, which is currently engaged in the development of fedratinib for the treatment of patients with myelofibrosis (MF) and polycythemia vera (PV).
Celgene agreed to pay an additional $1.4bn, depending on the receipt of milestone approvals from the US Food and Drug Administration.
Finally, the company will make payments depending on sales, with a maximum of $4.5bn due if annual net sales of Impact’s treatments cross $5bn.
Fedratinib is a highly selective oral small molecule JAK2 kinase inhibitor, which was assessed in 877 patients across 18 clinical trials.
It showed statistically significant improvements in the primary and secondary endpoints of splenic response and total symptom score in a randomized, placebo-controlled and phase III pivotal trial called Jakarta-1 for patients with treatment-naïve myelofibrosis.
Jakarta-2 is a multi-center and single-arm phase II trial evaluated fedratinib in myelofibrosis patients who have been found to be resistant or intolerant to ruxolitinib (Jakafi®), which is a JAK1/JAK2 inhibitor.
Fedratinib showed clinically better improvements in splenic response and total symptom score in the second-line setting.
Jakarta-2 study has been halted due to clinical hold on the fedratinib program by the US Food and Drug Administration (FDA), after reporting potential cases of Wernicke’s encephalopathy (WE) in eight out of 877 patients receiving one or more doses.
Celgene hematology and oncology president Nadim Ahmed said: “Myelofibrosis is a disease with high unmet medical need as the number of patients who are ineligible for or become resistant to existing therapy continues to increase.
Impact Biomedicines CEO John Hood said: “We launched Impact Biomedicines and based on our thorough review of the data, fedratinib presents a compelling risk benefit profile in both treatment-naïve patients and patients who are resistant or intolerant to other JAK2 therapies.”