The deal marks LFB's drive to increase its bioproduction facilities following its move into biotechnology last year.
The new company will be controlled by LFB subsidiary, LFB Biotechnologies, and will operate out of MAbgene's manufacturing site at Ales, southern France.
The terms of the current agreement stipulate that LFB Biotechnologies will acquire 41 per cent of the stock capital and 51 per cent of the voting rights in the new company for €3m upfront, meanwhile providing MAbgene with the funds needed to develop its activities, build new operating facilities and recruit additional personnel.
The objective is to fully acquire 100 per cent of MAbgene.
According to LFB Group chairman Christian Bechon, the integration of MAbgene and the investments made in the Languedoc Roussillon region on the Ales site "correspond to a true industrial logic and are fully in line with our commitment to growing the group in the biomanufacturing sector.
This operation will also enable us to become more autonomous in developing our own monoclonal antibodies."
MAbgene founder and chairman Patrick Henno said in a statement: "Partnering with a pharmaceutical group like LFB had become a decisive milestone for MAbgene, in view of our need to achieve a critical mass and respond to our customer's requirements in a setting which reconciles economic considerations with compliance with good manufacturing practice."
The new biotech company will manufacture commercial batches of monoclonal antibodies.
There are plans for expanding the plant, which currently features a pilot development unit and an existing Good Manufacturing Practice clinical batch production facility.
Henno will be appointed chief executive of the new company and existing MAbgene employees will stay on board.
LFB specializes in monoclonal antibodies and therapeutic proteins for treating rare and severe diseases.
The company entered into a major collaboration on transgenics with GTC Biotherapeutics in October last year.
MAbgene specializes in the production of antibodies and other glycoproteins in animal cell-based systems.