The pharma heavyweight will pay up to $120m (€92m) in a non-exclusive license deal to use Regeneron's VelocImmune technology to discover human monoclonal antibodies.
The work will be conducted at UK-based Cambridge Antibody Technology (CAT), which was acquired by AstraZeneca last June.
The deal is AstraZeneca's fourth in a week as the company restructures its business and supply chain to meet the challenge of industry-wide R&D costs rising despite fewer innovative drugs coming to market.
Part of AstraZeneca's aim is to build a biopharmaceutical capability.
AstraZeneca has said that: "Strengthening the pipeline, by enhancing our internal discovery and development and continued pursuit of external opportunities, remains the number one priority for the company."
The company hopes VelocImmune will be enable its internal research teams to discover antibodies faster and more efficiently.
"AstraZeneca is committed to becoming a leader in the area of biologicals and VelocImmune is an important part of our strategy to succeed in this field," said Jan Lundberg, head of global discovery research.
Monoclonal antibodies (MAbs) got their name because they are produced from a single type of immune cell.
The antibodies bind to a specific known target and so can be used as a research tool to detect and purify that substance, for example in target validation.
They can also be used clinically to deliver drugs to specific disease-related targets such as cancer tumour cells.
MAbs are produced by inducing an immune response in animal cells, typically from a mouse.
First-generation MAbs were limited by side effects and a tendency to lose efficacy over time.
Since then, there has been a progressive effort by scientists to make the antibodies more human culminating in the generation of genetically engineered mice that produce fully-human antibodies.
Regeneron's VelocImmune is one such technology.
The company states that its mouse cells can produce antibodies faster than other techniques, increasing research efficiency.
The VelocImmune mouse is created by replacing variable regions of mouse immune system genes with corresponding human variable sequences.
Unlike other technologies, where mice make antibodies with human constant regions, the VelocImmune mice have intact constant regions and therefore their immune system appears identical to normal mice.
This avoids problems caused by incomplete genetic controls potentially resulting in inefficient antibody production.
Problems can also be created if the antigen target of the MAbs is very similar in mice and in humans because the mice may produce two sets of antibodies: the MAb required and another antibody to target their own antigens.
However, Regeneron technology can prevent mice antigens from being produced by deactivating the relevant mice genes.
CAT will use its phage and ribosome display technologies to isolate specific antibodies from vast libraries of antibodies and their fragments.
AstraZeneca anticipates that the combination of CAT's display technologies and the VelocImmune platform will provide enormous potential for creating antibody therapeutics.
Regeneron will receive $20 million upfront and then between three and five additional $20 million annual payments.
AstraZeneca is not alone in their refocus as several of the industry's main players, including Pfizer and Roche, are being forced to re-examine their businesses in light of patent expirations, cheaper outsourcing and threats from generic competition.
Last week, AstraZeneca acquired Arrow Therapeutics and signed two licensing deals.
Arrow is a UK biotech which develops drug candidates for hepatitis C virus (HCV) and respiratory syncytial virus (RSV).
Arrow's most advanced compound is RSV604 for the treatment of RSV.
Currently in Phase II clinical trials, it was developed in collaboration with Novartis.
The two licensing deals cost AstraZeneca an initial $31m, possibly rising to $800m. The agreement with Palatin Technologies will focus on discovering obesity drugs that target melanocortin receptors and Argenta Discovery will collaborate with AstraZeneca to research improved bronchodilators to treat chronic obstructive pulmonary disease (COPD).
The latter partnership will focus on finding long acting muscarinic (M3) antagonist (LAMA) and dual acting muscarinic inhibitor-beta2 agonist drugs (MABAs).