Pharmaceutical giant Eli Lilly & Co., advised by Paul Weiss Rifkind Wharton & Garrison LLP, on Monday announced that it has agreed to buy Goodwin Procter LLP-led biotechnology firm Orna Therapeutics Inc. in a deal where Orna shareholders could receive up to $2.4 billion in cash.

Under the terms of the agreement, the purchase price includes an upfront payment and future payments based on the achievement of certain clinical development milestones, according to a Monday statement.

Watertown, Massachusetts-based Orna is a biotechnology firm focused on engineering immune cells in vivo, or in a living organism. The company is advancing a new class of therapeutics that uses engineered circular RNA paired with novel lipid nanoparticles to help the patient's body generate cell therapies that can treat underlying diseases, according to the statement.

Its lead program, called ORN-252, is a clinical trial-ready therapy that targets in vivo Chimeric Antigen Receptor T-cell (CAR-T) therapy designed to treat B cell-driven autoimmune diseases, the statement said.

"Early autologous CAR-T studies have shown the promise of cell therapy for patients with autoimmune diseases, but the complexity, cost, and logistics of ex vivo approaches make it challenging to deliver these breakthroughs to the broader population of patients who need them," said Francisco Ramírez-Valle, Eli Lilly senior vice president and head of immunology research and early clinical development. "We look forward to working with Orna colleagues to potentially unlock an entirely new class of genetic medicines."

According to the statement, current experiments show that Orna's circular RNA platform could deliver more durable expression of therapeutic proteins and unlock medicines "that are not feasible" with current RNA or cell therapy platforms.

"At Orna, we believe our circular RNA technology paired with our best-in-class LNP delivery platform have the potential to unlock in vivo CAR-T therapies for patients across a wide range of B cell-driven autoimmune diseases," said Orna CEO Joe Bolen. "We are excited to join forces with Lilly, an industry leader in the development of patient-centric therapeutics to realize the full potential of these technologies."

The Paul Weiss team advising Eli Lilly included partners Krishna Veeraraghavan, Chelsea Darnell, and Jeffrey D. Osterman.

Full legal counsel information for the Goodwin team advising Orna was not immediately available Monday.