An upfront payment of $87.5m has been made by Pfizer for the minority equity interest and exclusive option.
As part of the deal, Pfizer will make additional potential payments of about $512.5m upon option exercise and potential launch of any product that may result from this agreement.
Pfizer Worldwide Research and Development president Mikael Dolsten said: "Pfizer is committed to advancing the science to address the high unmet medical need in Acute Kidney Injury.
"Clinical data for recAP show the potential to uniquely address Acute Kidney Injury in the setting of sepsis, and we look forward to working with our partners at AM-Pharma as we aim to accelerate the development of recAP into a potential first-in-class treatment for patients."
AM-Pharma CEO Erik van den Berg said: "This agreement is a significant step for AM-Pharma, and we welcome Pfizer as a shareholder and dedicated partner.
"This deal not only provides good shareholder value, but provides the next step in the development of recAP as a potential treatment for patients with Acute Kidney Injury and other inflammatory diseases."
The option to acquire remaining stake in the Dutch firm becomes exercisable after completion of a Phase II trial assessing AM’s recombinant human Alkaline Phosphatase (recAP) to treat acute kidney injury (AKI) related to sepsis.
Currently, there are no drugs approved for this condition and the only treatment option is dialysis and supportive care.
According to the Dutch firm, results from the current Phase II trial for recAP are expected to be reported in the second half of 2016.
Image: Pfizer world headquarters. Photo: courtesy of Jim.henderson.