The acquisition is in accordance with the development, option and stock purchase agreement (DOSPA) entered by Fortress Biotech, Caelum, Alexion and others.
Biopharmaceutical company Fortress founded Caelum, which creates therapies for rare and fatal diseases.
According to the deal announced in September, Caelum was acquired by Alexion for the agreed option exercise cost of nearly $150m.
All the current stockholders of Caelum will receive distributions.
Furthermore, Caelum stakeholders are eligible to receive further potential payments which would total to up to $350m on meeting regulatory as well as commercial milestones.
In 2019, Caelum and Alexion initially entered a partnership through which Alexion acquired a minority equity interest and the exclusive option for the acquisition of the remaining of Caelum’s equity.
With the Caelum acquisition, Alexion will gain rights to the former’s fibril-reactive monoclonal antibody (mAb), CAEL-101, to treat light chain (AL) amyloidosis.
CAEL-101 is an antibody that can potentially attach to misfolded light chain proteins and amyloid and shows binding to both kappa and lambda subtypes.
At present, CAEL-101 is being analysed in the Phase III Cardiac Amyloid Reaching for Extended Survival clinical programme administered along with standard-of-care treatment for AL amyloidosis.
Additionally, two Phase III trials of the antibody in Mayo stage IIIa disease patients and those with Mayo stage IIIb disease, are progressing parallelly.
A rare disease, AL amyloidosis causes accumulation of misfolded amyloid proteins in organs in the body, leading to substantial organ damage and failure.
AstraZeneca completed the acquisition of Alexion in July this year, which triggered an option to takeover Caelum within a six-month duration.